The Journal of Family Practice

An 11-year-old boy sought care at a small village’s health center in Panama for scalp itching and subtle hair loss. He was seen by a family physician (RU) and a team of medical students who were there as part of a humanitarian trip. The patient denied any hair pulling. He had a history of treatment for head lice.

Our physical examination revealed mild alopecia and scaling on the scalp (FIGURE 1), but what we saw through the dermatoscope (FIGURE 2) made the diagnosis clear.

WHAT IS YOUR DIAGNOSIS?
HOW WOULD YOU TREAT THIS PATIENT?

Diagnosis: Tinea capitis

On dermatoscopic examination (10× magnification), there were numerous “black dots” or broken hair shafts within patches of hair loss (FIGURE 3), which is indicative of tinea capitis.^1,2 This condition causes hair shafts to break, creating “comma hairs” and black dots. The hairs are uniform in thickness and color and bend distally, like a comma.³

Tinea capitis (commonly called ringworm of the scalp) is a fungal infection caused by Trichophyton and Microsporum dermatophytes. It is the most common pediatric dermatophyte infection in the world; the usual age of onset is 5 to 10 years.² The incidence of tinea capitis in the United States is not known because cases are no longer registered by public health agencies. That said, a Northern California study that tracked occurrences in children younger than 15 years from 1998 to 2007 found that the incidence was on the decline and lower in girls compared to boys (111.9 vs 146.4, respectively, in 1998; 27.9 vs 39.9, respectively, in 2007).⁴ Incidence rates were calculated per 10,000 eligible children.⁴

Tinea capitis can spread by contact with infected individuals and contaminated objects, including combs, towels, toys, and bedding.¹ Fungal spores can remain viable on these surfaces for months.

In a study of 69 patients with tinea capitis (23 females, 46 males; mean age, 12 years), the risk factors for spreading infection included participation in sports, contact with an animal, a recent haircut, and use of a swimming pool.⁵

4 conditions you’ll want to rule out

The following conditions should be considered as part of the differential when a patient presents with an itchy scalp and/or hair loss.

Continue to: Psoriasis of the scalp...

Psoriasis of the scalp is characterized by scaling of the scalp along with crusted plaques. It is often accompanied by similar psoriatic plaques on the elbows, knees, and other areas of the body. Examination of our patient showed no psoriatic plaques.

Seborrhea of the scalp (also known as dandruff) is a very common diagnosis. However, it is unlikely to cause hair loss. It has widespread involvement of the scalp compared to tinea capitis, which is local and patchy. Our patient’s patches of hair loss indicated that seborrhea was unlikely.

Alopecia areata. Individuals develop this condition due to an autoimmune process affecting hair follicles. However, the resulting hair loss does not cause significant scaling, inflammation, scarring, or pain in the affected area. Further, this condition can cause the loss of the entire hair shaft.

Trichotillomania is an impulse control disorder that causes patients to pull out their own hair. There is no scaling of the scalp in this condition.

A dermatoscope can beuseful in making the Dx

Although clinical appearance and patient presentation are adequate to establish the diagnosis of tinea capitis, this case demonstrates the utility of a dermatoscope in making the diagnosis of tinea capitis. Previous studies have shown that dermoscopy allows for rapid identification of the broken hair shafts, which are a key distinction from alopecia areata.^3,6

Microscopic inspection. Samples from the scaling of the scalp can be examined with potassium hydroxide (KOH) on a microscope slide. Hyphae, spores, and endo/ectothrix invasion can be seen through the microsope.  

Continue to: Laboratory testing is helpful, but not needed.

Newer antifungalsprovide a Tx advantage

Oral antifungal medications are the treatment of choice for tinea capitis. Newer antifungals, such as terbinafine and fluconazole, require a 3- to 6-week course compared to the standard 6- to 8-week course of griseofulvin.¹ Also, antifungal shampoos—such as those that contain selenium sulfide—may be used for topical treatment but only as adjuvant therapy.^1,2

For our patient, we dispensed a 3-week course of oral fluconazole, 3 to 6 mg/kg, to be given daily by his parents. We also recommended the use of an antidandruff shampoo, if possible. The treatment outcome was not known because our team’s humanitarian global health trip had ended.

An 11-year-old boy sought care at a small village’s health center in Panama for scalp itching and subtle hair loss. He was seen by a family physician (RU) and a team of medical students who were there as part of a humanitarian trip. The patient denied any hair pulling. He had a history of treatment for head lice.

Our physical examination revealed mild alopecia and scaling on the scalp (FIGURE 1), but what we saw through the dermatoscope (FIGURE 2) made the diagnosis clear.

WHAT IS YOUR DIAGNOSIS?
HOW WOULD YOU TREAT THIS PATIENT?

Diagnosis: Tinea capitis

On dermatoscopic examination (10× magnification), there were numerous “black dots” or broken hair shafts within patches of hair loss (FIGURE 3), which is indicative of tinea capitis.^1,2 This condition causes hair shafts to break, creating “comma hairs” and black dots. The hairs are uniform in thickness and color and bend distally, like a comma.³

Tinea capitis (commonly called ringworm of the scalp) is a fungal infection caused by Trichophyton and Microsporum dermatophytes. It is the most common pediatric dermatophyte infection in the world; the usual age of onset is 5 to 10 years.² The incidence of tinea capitis in the United States is not known because cases are no longer registered by public health agencies. That said, a Northern California study that tracked occurrences in children younger than 15 years from 1998 to 2007 found that the incidence was on the decline and lower in girls compared to boys (111.9 vs 146.4, respectively, in 1998; 27.9 vs 39.9, respectively, in 2007).⁴ Incidence rates were calculated per 10,000 eligible children.⁴

Tinea capitis can spread by contact with infected individuals and contaminated objects, including combs, towels, toys, and bedding.¹ Fungal spores can remain viable on these surfaces for months.

In a study of 69 patients with tinea capitis (23 females, 46 males; mean age, 12 years), the risk factors for spreading infection included participation in sports, contact with an animal, a recent haircut, and use of a swimming pool.⁵

4 conditions you’ll want to rule out

The following conditions should be considered as part of the differential when a patient presents with an itchy scalp and/or hair loss.

Continue to: Psoriasis of the scalp...

Psoriasis of the scalp is characterized by scaling of the scalp along with crusted plaques. It is often accompanied by similar psoriatic plaques on the elbows, knees, and other areas of the body. Examination of our patient showed no psoriatic plaques.

Seborrhea of the scalp (also known as dandruff) is a very common diagnosis. However, it is unlikely to cause hair loss. It has widespread involvement of the scalp compared to tinea capitis, which is local and patchy. Our patient’s patches of hair loss indicated that seborrhea was unlikely.

Alopecia areata. Individuals develop this condition due to an autoimmune process affecting hair follicles. However, the resulting hair loss does not cause significant scaling, inflammation, scarring, or pain in the affected area. Further, this condition can cause the loss of the entire hair shaft.

Trichotillomania is an impulse control disorder that causes patients to pull out their own hair. There is no scaling of the scalp in this condition.

A dermatoscope can beuseful in making the Dx

Although clinical appearance and patient presentation are adequate to establish the diagnosis of tinea capitis, this case demonstrates the utility of a dermatoscope in making the diagnosis of tinea capitis. Previous studies have shown that dermoscopy allows for rapid identification of the broken hair shafts, which are a key distinction from alopecia areata.^3,6

Microscopic inspection. Samples from the scaling of the scalp can be examined with potassium hydroxide (KOH) on a microscope slide. Hyphae, spores, and endo/ectothrix invasion can be seen through the microsope.  

Continue to: Laboratory testing is helpful, but not needed.

Newer antifungalsprovide a Tx advantage

Oral antifungal medications are the treatment of choice for tinea capitis. Newer antifungals, such as terbinafine and fluconazole, require a 3- to 6-week course compared to the standard 6- to 8-week course of griseofulvin.¹ Also, antifungal shampoos—such as those that contain selenium sulfide—may be used for topical treatment but only as adjuvant therapy.^1,2

For our patient, we dispensed a 3-week course of oral fluconazole, 3 to 6 mg/kg, to be given daily by his parents. We also recommended the use of an antidandruff shampoo, if possible. The treatment outcome was not known because our team’s humanitarian global health trip had ended.

An 11-year-old boy sought care at a small village’s health center in Panama for scalp itching and subtle hair loss. He was seen by a family physician (RU) and a team of medical students who were there as part of a humanitarian trip. The patient denied any hair pulling. He had a history of treatment for head lice.

Our physical examination revealed mild alopecia and scaling on the scalp (FIGURE 1), but what we saw through the dermatoscope (FIGURE 2) made the diagnosis clear.

WHAT IS YOUR DIAGNOSIS?
HOW WOULD YOU TREAT THIS PATIENT?

Diagnosis: Tinea capitis

On dermatoscopic examination (10× magnification), there were numerous “black dots” or broken hair shafts within patches of hair loss (FIGURE 3), which is indicative of tinea capitis.^1,2 This condition causes hair shafts to break, creating “comma hairs” and black dots. The hairs are uniform in thickness and color and bend distally, like a comma.³

Tinea capitis (commonly called ringworm of the scalp) is a fungal infection caused by Trichophyton and Microsporum dermatophytes. It is the most common pediatric dermatophyte infection in the world; the usual age of onset is 5 to 10 years.² The incidence of tinea capitis in the United States is not known because cases are no longer registered by public health agencies. That said, a Northern California study that tracked occurrences in children younger than 15 years from 1998 to 2007 found that the incidence was on the decline and lower in girls compared to boys (111.9 vs 146.4, respectively, in 1998; 27.9 vs 39.9, respectively, in 2007).⁴ Incidence rates were calculated per 10,000 eligible children.⁴

Tinea capitis can spread by contact with infected individuals and contaminated objects, including combs, towels, toys, and bedding.¹ Fungal spores can remain viable on these surfaces for months.

In a study of 69 patients with tinea capitis (23 females, 46 males; mean age, 12 years), the risk factors for spreading infection included participation in sports, contact with an animal, a recent haircut, and use of a swimming pool.⁵

4 conditions you’ll want to rule out

The following conditions should be considered as part of the differential when a patient presents with an itchy scalp and/or hair loss.

Continue to: Psoriasis of the scalp...

Psoriasis of the scalp is characterized by scaling of the scalp along with crusted plaques. It is often accompanied by similar psoriatic plaques on the elbows, knees, and other areas of the body. Examination of our patient showed no psoriatic plaques.

Seborrhea of the scalp (also known as dandruff) is a very common diagnosis. However, it is unlikely to cause hair loss. It has widespread involvement of the scalp compared to tinea capitis, which is local and patchy. Our patient’s patches of hair loss indicated that seborrhea was unlikely.

Alopecia areata. Individuals develop this condition due to an autoimmune process affecting hair follicles. However, the resulting hair loss does not cause significant scaling, inflammation, scarring, or pain in the affected area. Further, this condition can cause the loss of the entire hair shaft.

Trichotillomania is an impulse control disorder that causes patients to pull out their own hair. There is no scaling of the scalp in this condition.

A dermatoscope can beuseful in making the Dx

Although clinical appearance and patient presentation are adequate to establish the diagnosis of tinea capitis, this case demonstrates the utility of a dermatoscope in making the diagnosis of tinea capitis. Previous studies have shown that dermoscopy allows for rapid identification of the broken hair shafts, which are a key distinction from alopecia areata.^3,6

Microscopic inspection. Samples from the scaling of the scalp can be examined with potassium hydroxide (KOH) on a microscope slide. Hyphae, spores, and endo/ectothrix invasion can be seen through the microsope.  

Continue to: Laboratory testing is helpful, but not needed.

Newer antifungalsprovide a Tx advantage

Oral antifungal medications are the treatment of choice for tinea capitis. Newer antifungals, such as terbinafine and fluconazole, require a 3- to 6-week course compared to the standard 6- to 8-week course of griseofulvin.¹ Also, antifungal shampoos—such as those that contain selenium sulfide—may be used for topical treatment but only as adjuvant therapy.^1,2

For our patient, we dispensed a 3-week course of oral fluconazole, 3 to 6 mg/kg, to be given daily by his parents. We also recommended the use of an antidandruff shampoo, if possible. The treatment outcome was not known because our team’s humanitarian global health trip had ended.

Here is our problem: Family medicine has allowed itself, and its patients, to be picked apart by the forces of reductionism and a system that profits from the sick and suffering. We have lost sight of our purpose and our vision to care for the whole person. We have lost our way as healers.

The result is not only a decline in the specialty of family medicine as a leader in primary care but declining value and worsening outcomes in health care overall. We need to get our mojo back. We can do this by focusing less on trying to be all things to all people at all times, and more on creating better models for preventing, managing, and reversing chronic disease. This means providing health care that is person centered, relationship based, recovery focused, and paid for comprehensively.

I call this model Advanced Primary Care, or APC ­(FIGURE). In this article, I describe exemplars of APC from across the United States. I also provide tools to help you recover its central feature, holism—care of the whole person in mind, body, community, and spirit—in your practice, thus returning us to the core purpose of family medicine.

Holism is central to family medicine

More than 40 years ago, psychiatrist George Engel, MD, published a seminal article in Science that inspired a radical vision of how health care should be practiced.¹ Called the biopsychosocial model, it stated what, in some ways, is obvious: Human beings are complex organisms embedded in complex environments made up of distinct, yet interacting, dimensions. These dimensions included physical, psychological, and social components. Engel’s radical proposition was that these dimensions are definable and measurable and that good medicine cannot afford to ignore any of them.

Engel’s assertion that good medicine requires holism was a clarion call during a time of rapidly expanding knowledge and subspecialization. That call was the inspiration for a new medical specialty called family medicine, which dared to proclaim that the best way to heal was to care for the whole person within the context of that person’s emotional and social environment. Family medicine reinvigorated primary care and grew rapidly, becoming a preeminent primary care specialty in the United States.

Continue to : Reductionism is relentless

Reductionism is relentless

But the forces of medicine were—and still are—driving relentlessly the other way. The science of the small and particular (reductionism), with dazzling technology and exploding subspecialty knowledge, and backed by powerful economic drivers, rewards health care for pulling the patient and the medical profession apart. We pay more to those who treat small parts of a person over a short period than to those who attend to the whole person over the lifetime.

Today, family medicine—for all of its common sense, scientific soundness, connectedness to patients, and demonstrated value—struggles to survive.^2-6 The holistic vision of Engel is declining. The struggle in primary care is that its holistic vision gets co-opted by specialized medical science—and then it desperately attempts to apply those small and specialized tools to the care of patients in their wholeness. Holism is largely dead in health care, and everyone pays the consequences.⁷

Health care is losing its value

The damage from this decline in holism is not just to primary care but to the value of health care in general. Most medical care being delivered today—comprising diagnosis, treatment, and payment (the innermost circle of the FIGURE)—is not producing good health.⁸ Only 15% to 20% of the healing of an individual or a population comes from health care.⁹ The rest—nearly 80%—comes from other factors rarely addressed in the health care system: behavioral and lifestyle choices that people make in their daily life, including those related to food, movement, sleep, stress, and substance use.¹⁰ Increasingly, it is the economic and social determinants of health that influence this behavior and have a greater impact on health and lifespan than physiology or genes.¹¹ The same social determinants of health also influence patients’ ability to obtain medical care and pursue a meaningful life.¹²

The result of this decline in holism and in the value of health care in general has been a relentless rise in the cost of medical care^13-15 and the need for social services; declining life expectancy^16,17 and quality of life¹⁸; growing patient dissatisfaction; and burnout in providers.^19,20 Health care has become, as investor and business leader Warren Buffet remarked, the “tapeworm” of the economy and a major contributor to growing disparities in health and well-being between the haves and have-nots.²¹ Engel’s prediction that good medicine cannot afford to ignore holism has come to pass.

Family medicine has allowed itself, and patients, to be picked apart by forces of reductionism and a system that profits from the sick and suffering.

3-step solution:Return to whole-person care

Family medicine needs to return to whole-person care, but it can do so only if it attends to, and effectively delivers on, the prevention, treatment, and reversal of chronic disease and the enhancement of health and well-­being. This can happen only if family medicine stops trying to be all things to all people at all times and, instead, focuses on what matters to the patient as a person.

Continue to: This means that the core...

This means that the core interaction in family medicine must be to assess the whole person—mind, body, social, spirit—and help that person make changes that improve his/her/their health and well-being based on his/her/their individualized needs and social context. In other words, family medicine needs to deliver a holistic model of APC that is person centered, relationship based, recovery focused, and paid for comprehensively.

How does one get from “standard” primary care of today (the innermost circle of the FIGURE) to a framework that truly delivers on the promise of healing? I propose 3 steps to return holism to family medicine.

STEP 1: Start with comprehensive, coordinated primary care. We know that this works. Starfield and others demonstrated this 2 decades ago, defining and devising what we know as quality primary care—characterized by first-contact care, comprehensive primary care (CPC), continuous care, and coordinated care.²² This type of primary care improves outcomes, lowers costs, and is satisfying to patients and providers.²³ The physician cares for the patient throughout that person’s entire life cycle and provides all evidence-based services needed to prevent and treat common conditions. Comprehensive primary care is positioned in the first circle outward from the innermost circle of the FIGURE.

As medicine has become increasingly complex and subspecialized, however, the ability to coordinate care is often frayed, adding cost and reducing quality.^24-26 Today, comprehensive primary care needs enhanced coordination. At a minimum, this means coordinating services for:

• chronic disease management (outpatient and inpatient transitions and emergency department use)
• referral (specialists and tests)
• pharmacy services (including delivery and patient education support).

An example of a primary care system that meets these requirements is the Catalyst Health Network in central Texas, which supplies coordination services to more than 1000 comprehensive primary care practices and 1.5 million patients.²⁷ The Catalyst Network makes money for those practices, saves money in the system, enhances patient and provider satisfaction, and improves population health in the community.²⁷ I call this enhanced primary care (EPC), shown in the second circle out from the innermost circle of the FIGURE.

STEP 2: Add integrative medicine and mental health. EPC improves fragmented care but does not necessarily address a patient’s underlying determinants of healing. We know that health behaviors such as smoking cessation, avoidance of alcohol and drug abuse, improved diet, physical activity, sleep, and stress management contribute 40% to 60% of a person’s and a population’s health.¹⁰ In addition, evidence shows that behavioral health services, along with lifestyle change support, can even reverse many chronic diseases seen in primary care, such as obesity, diabetes, hypertension, cardiovascular disease, depression, and substance abuse.^28,29

Continue to: Therefore, we need to add...

Therefore, we need to add routine mental health services and nonpharmacotherapeutic approaches (eg, complementary and alternative medicine) to primary care.³⁰ Doing so requires that behavioral change and self-care become a central feature of the ­doctor–patient dialogue and team skills³¹ and be added to primary care.^30,31 I call this integrative primary care (IPC), shown on the left side in the third circle out from the innermost circle of the FIGURE.
 

Only 15% to 20% of individual and population healing comes from health care; the rest, from behavioral and lifestyle choices rarely addressed in primary care.

An example of IPC is Whole Health, an initiative of the US Veteran’s Health Administration. Whole Health empowers and informs a person-centered approach and integrates it into the delivery of routine care.³² Evaluation of Whole Health implementation, which involved more than 130,000 veterans followed for 2 years, found a net overall reduction in the total cost of care of 20%—saving nearly $650 million or, on average, more than $4500 per veteran.³³

STEP 3: Address social determinants of health. Primary care will not fully be part of the solution for producing health and well-being unless it becomes instrumental in addressing the social determinants of health (SDH), defined as “… conditions in the environments in which people are born, live, learn, work, play, worship, and age that affect a wide range of health, functioning, and quality-of-life outcomes and risks.”³⁴ These determinants include not only basic needs, such as housing, food, safety, and transportation (ie, social needs), but also what are known as structural determinants, such as income, education, language, and racial and ethnic bias. Health care cannot solve all of these social ills,but it is increasingly being called on to be the nexus of coordination for services that address these needs when they affect health outcomes.^35,36

Examples of health systems that provide for social needs include the free “food prescription” program of Pennsylvania’s Geisinger Health System, for patients with diabetes who do not have the resources to pay for food.³⁷ This approach improves blood glucose control by patients and saves money on medications and other interventions. Similarly, Kaiser Permanente has experimented with housing vouchers for homeless patients,and most Federally Qualified Health Centers provide bus or other transportation tickets to patients for their appointments and free or discounted tests and specialty care.³⁸

Implementing whole-person care for all

I propose that we make APC the central focus of family medicine. This model would comprise CPC, plus EPC, IPC, and community coordination to address SDH. This is expressed as:

CPC + EPC + IPC + SDH = APC

Continue to: APC would mean...

APC would mean health for the whole person and for all people. Again, the FIGURE shows how this model, encompassing the entire third circle out from the center circle, could be created from current models of care.

How do we pay for this? We already do—and way too much. The problem is not lack of money in the health care system but how it is organized and distributed. The Centers for Medicare and Medicaid Services and other payers are developing value-based payment models to help cover this type of care,³⁹ but payers cannot pay for something if it is unavailable.

Can family physicians deliver APC? I believe they can, and have given a few examples here to show how this is already happening. To help primary care providers start to deliver APC in their system, my team and I have built the HOPE (Healing Oriented Practices & Environments) Note Toolkit to use in daily practice.⁴⁰ These and other tools are being used by a number of large hospital systems and health care networks around the country. (You can download the HOPE Note Toolkit, at no cost, at https://drwaynejonas.com/­resources/hope-note/.)

At a minimum, comprehensive primary care needs to coordinate services for chronic disease management, referral (to specialists and testing), and pharmacy services.

Whatever we call this new type of primary care, it needs to care for the whole person and to be available to all. It finds expression in these assertions:

• We cannot ignore an essential part of what a human being is and expect them to heal or become whole.
• We cannot ignore essential people in our communities and expect our costs to go down or our compassion to go up.
• We need to stop allowing family medicine to be co-opted by reductionism and its profits.

In sum, we need a new vision of primary care—like Engel’s holistic vision in the 1970s—to motivate us, and we need to return to fundamental concepts of how healing works in medicine.⁴¹

CORRESPONDENCE

Wayne B. Jonas, MD, Samueli Integrative Health Programs, 1800 Diagonal Road, Suite 617, Alexandria, VA 22314; wayne@drwaynejonas.com.

Here is our problem: Family medicine has allowed itself, and its patients, to be picked apart by the forces of reductionism and a system that profits from the sick and suffering. We have lost sight of our purpose and our vision to care for the whole person. We have lost our way as healers.

The result is not only a decline in the specialty of family medicine as a leader in primary care but declining value and worsening outcomes in health care overall. We need to get our mojo back. We can do this by focusing less on trying to be all things to all people at all times, and more on creating better models for preventing, managing, and reversing chronic disease. This means providing health care that is person centered, relationship based, recovery focused, and paid for comprehensively.

I call this model Advanced Primary Care, or APC ­(FIGURE). In this article, I describe exemplars of APC from across the United States. I also provide tools to help you recover its central feature, holism—care of the whole person in mind, body, community, and spirit—in your practice, thus returning us to the core purpose of family medicine.

Holism is central to family medicine

More than 40 years ago, psychiatrist George Engel, MD, published a seminal article in Science that inspired a radical vision of how health care should be practiced.¹ Called the biopsychosocial model, it stated what, in some ways, is obvious: Human beings are complex organisms embedded in complex environments made up of distinct, yet interacting, dimensions. These dimensions included physical, psychological, and social components. Engel’s radical proposition was that these dimensions are definable and measurable and that good medicine cannot afford to ignore any of them.

Engel’s assertion that good medicine requires holism was a clarion call during a time of rapidly expanding knowledge and subspecialization. That call was the inspiration for a new medical specialty called family medicine, which dared to proclaim that the best way to heal was to care for the whole person within the context of that person’s emotional and social environment. Family medicine reinvigorated primary care and grew rapidly, becoming a preeminent primary care specialty in the United States.

Continue to : Reductionism is relentless

Reductionism is relentless

But the forces of medicine were—and still are—driving relentlessly the other way. The science of the small and particular (reductionism), with dazzling technology and exploding subspecialty knowledge, and backed by powerful economic drivers, rewards health care for pulling the patient and the medical profession apart. We pay more to those who treat small parts of a person over a short period than to those who attend to the whole person over the lifetime.

Today, family medicine—for all of its common sense, scientific soundness, connectedness to patients, and demonstrated value—struggles to survive.^2-6 The holistic vision of Engel is declining. The struggle in primary care is that its holistic vision gets co-opted by specialized medical science—and then it desperately attempts to apply those small and specialized tools to the care of patients in their wholeness. Holism is largely dead in health care, and everyone pays the consequences.⁷

Health care is losing its value

The damage from this decline in holism is not just to primary care but to the value of health care in general. Most medical care being delivered today—comprising diagnosis, treatment, and payment (the innermost circle of the FIGURE)—is not producing good health.⁸ Only 15% to 20% of the healing of an individual or a population comes from health care.⁹ The rest—nearly 80%—comes from other factors rarely addressed in the health care system: behavioral and lifestyle choices that people make in their daily life, including those related to food, movement, sleep, stress, and substance use.¹⁰ Increasingly, it is the economic and social determinants of health that influence this behavior and have a greater impact on health and lifespan than physiology or genes.¹¹ The same social determinants of health also influence patients’ ability to obtain medical care and pursue a meaningful life.¹²

The result of this decline in holism and in the value of health care in general has been a relentless rise in the cost of medical care^13-15 and the need for social services; declining life expectancy^16,17 and quality of life¹⁸; growing patient dissatisfaction; and burnout in providers.^19,20 Health care has become, as investor and business leader Warren Buffet remarked, the “tapeworm” of the economy and a major contributor to growing disparities in health and well-being between the haves and have-nots.²¹ Engel’s prediction that good medicine cannot afford to ignore holism has come to pass.

Family medicine has allowed itself, and patients, to be picked apart by forces of reductionism and a system that profits from the sick and suffering.

3-step solution:Return to whole-person care

Family medicine needs to return to whole-person care, but it can do so only if it attends to, and effectively delivers on, the prevention, treatment, and reversal of chronic disease and the enhancement of health and well-­being. This can happen only if family medicine stops trying to be all things to all people at all times and, instead, focuses on what matters to the patient as a person.

Continue to: This means that the core...

This means that the core interaction in family medicine must be to assess the whole person—mind, body, social, spirit—and help that person make changes that improve his/her/their health and well-being based on his/her/their individualized needs and social context. In other words, family medicine needs to deliver a holistic model of APC that is person centered, relationship based, recovery focused, and paid for comprehensively.

How does one get from “standard” primary care of today (the innermost circle of the FIGURE) to a framework that truly delivers on the promise of healing? I propose 3 steps to return holism to family medicine.

STEP 1: Start with comprehensive, coordinated primary care. We know that this works. Starfield and others demonstrated this 2 decades ago, defining and devising what we know as quality primary care—characterized by first-contact care, comprehensive primary care (CPC), continuous care, and coordinated care.²² This type of primary care improves outcomes, lowers costs, and is satisfying to patients and providers.²³ The physician cares for the patient throughout that person’s entire life cycle and provides all evidence-based services needed to prevent and treat common conditions. Comprehensive primary care is positioned in the first circle outward from the innermost circle of the FIGURE.

As medicine has become increasingly complex and subspecialized, however, the ability to coordinate care is often frayed, adding cost and reducing quality.^24-26 Today, comprehensive primary care needs enhanced coordination. At a minimum, this means coordinating services for:

• chronic disease management (outpatient and inpatient transitions and emergency department use)
• referral (specialists and tests)
• pharmacy services (including delivery and patient education support).

An example of a primary care system that meets these requirements is the Catalyst Health Network in central Texas, which supplies coordination services to more than 1000 comprehensive primary care practices and 1.5 million patients.²⁷ The Catalyst Network makes money for those practices, saves money in the system, enhances patient and provider satisfaction, and improves population health in the community.²⁷ I call this enhanced primary care (EPC), shown in the second circle out from the innermost circle of the FIGURE.

STEP 2: Add integrative medicine and mental health. EPC improves fragmented care but does not necessarily address a patient’s underlying determinants of healing. We know that health behaviors such as smoking cessation, avoidance of alcohol and drug abuse, improved diet, physical activity, sleep, and stress management contribute 40% to 60% of a person’s and a population’s health.¹⁰ In addition, evidence shows that behavioral health services, along with lifestyle change support, can even reverse many chronic diseases seen in primary care, such as obesity, diabetes, hypertension, cardiovascular disease, depression, and substance abuse.^28,29

Continue to: Therefore, we need to add...

Therefore, we need to add routine mental health services and nonpharmacotherapeutic approaches (eg, complementary and alternative medicine) to primary care.³⁰ Doing so requires that behavioral change and self-care become a central feature of the ­doctor–patient dialogue and team skills³¹ and be added to primary care.^30,31 I call this integrative primary care (IPC), shown on the left side in the third circle out from the innermost circle of the FIGURE.
 

Only 15% to 20% of individual and population healing comes from health care; the rest, from behavioral and lifestyle choices rarely addressed in primary care.

An example of IPC is Whole Health, an initiative of the US Veteran’s Health Administration. Whole Health empowers and informs a person-centered approach and integrates it into the delivery of routine care.³² Evaluation of Whole Health implementation, which involved more than 130,000 veterans followed for 2 years, found a net overall reduction in the total cost of care of 20%—saving nearly $650 million or, on average, more than $4500 per veteran.³³

STEP 3: Address social determinants of health. Primary care will not fully be part of the solution for producing health and well-being unless it becomes instrumental in addressing the social determinants of health (SDH), defined as “… conditions in the environments in which people are born, live, learn, work, play, worship, and age that affect a wide range of health, functioning, and quality-of-life outcomes and risks.”³⁴ These determinants include not only basic needs, such as housing, food, safety, and transportation (ie, social needs), but also what are known as structural determinants, such as income, education, language, and racial and ethnic bias. Health care cannot solve all of these social ills,but it is increasingly being called on to be the nexus of coordination for services that address these needs when they affect health outcomes.^35,36

Examples of health systems that provide for social needs include the free “food prescription” program of Pennsylvania’s Geisinger Health System, for patients with diabetes who do not have the resources to pay for food.³⁷ This approach improves blood glucose control by patients and saves money on medications and other interventions. Similarly, Kaiser Permanente has experimented with housing vouchers for homeless patients,and most Federally Qualified Health Centers provide bus or other transportation tickets to patients for their appointments and free or discounted tests and specialty care.³⁸

Implementing whole-person care for all

I propose that we make APC the central focus of family medicine. This model would comprise CPC, plus EPC, IPC, and community coordination to address SDH. This is expressed as:

CPC + EPC + IPC + SDH = APC

Continue to: APC would mean...

APC would mean health for the whole person and for all people. Again, the FIGURE shows how this model, encompassing the entire third circle out from the center circle, could be created from current models of care.

How do we pay for this? We already do—and way too much. The problem is not lack of money in the health care system but how it is organized and distributed. The Centers for Medicare and Medicaid Services and other payers are developing value-based payment models to help cover this type of care,³⁹ but payers cannot pay for something if it is unavailable.

Can family physicians deliver APC? I believe they can, and have given a few examples here to show how this is already happening. To help primary care providers start to deliver APC in their system, my team and I have built the HOPE (Healing Oriented Practices & Environments) Note Toolkit to use in daily practice.⁴⁰ These and other tools are being used by a number of large hospital systems and health care networks around the country. (You can download the HOPE Note Toolkit, at no cost, at https://drwaynejonas.com/­resources/hope-note/.)

At a minimum, comprehensive primary care needs to coordinate services for chronic disease management, referral (to specialists and testing), and pharmacy services.

Whatever we call this new type of primary care, it needs to care for the whole person and to be available to all. It finds expression in these assertions:

• We cannot ignore an essential part of what a human being is and expect them to heal or become whole.
• We cannot ignore essential people in our communities and expect our costs to go down or our compassion to go up.
• We need to stop allowing family medicine to be co-opted by reductionism and its profits.

In sum, we need a new vision of primary care—like Engel’s holistic vision in the 1970s—to motivate us, and we need to return to fundamental concepts of how healing works in medicine.⁴¹

CORRESPONDENCE

Wayne B. Jonas, MD, Samueli Integrative Health Programs, 1800 Diagonal Road, Suite 617, Alexandria, VA 22314; wayne@drwaynejonas.com.

Here is our problem: Family medicine has allowed itself, and its patients, to be picked apart by the forces of reductionism and a system that profits from the sick and suffering. We have lost sight of our purpose and our vision to care for the whole person. We have lost our way as healers.

The result is not only a decline in the specialty of family medicine as a leader in primary care but declining value and worsening outcomes in health care overall. We need to get our mojo back. We can do this by focusing less on trying to be all things to all people at all times, and more on creating better models for preventing, managing, and reversing chronic disease. This means providing health care that is person centered, relationship based, recovery focused, and paid for comprehensively.

I call this model Advanced Primary Care, or APC ­(FIGURE). In this article, I describe exemplars of APC from across the United States. I also provide tools to help you recover its central feature, holism—care of the whole person in mind, body, community, and spirit—in your practice, thus returning us to the core purpose of family medicine.

Holism is central to family medicine

More than 40 years ago, psychiatrist George Engel, MD, published a seminal article in Science that inspired a radical vision of how health care should be practiced.¹ Called the biopsychosocial model, it stated what, in some ways, is obvious: Human beings are complex organisms embedded in complex environments made up of distinct, yet interacting, dimensions. These dimensions included physical, psychological, and social components. Engel’s radical proposition was that these dimensions are definable and measurable and that good medicine cannot afford to ignore any of them.

Engel’s assertion that good medicine requires holism was a clarion call during a time of rapidly expanding knowledge and subspecialization. That call was the inspiration for a new medical specialty called family medicine, which dared to proclaim that the best way to heal was to care for the whole person within the context of that person’s emotional and social environment. Family medicine reinvigorated primary care and grew rapidly, becoming a preeminent primary care specialty in the United States.

Continue to : Reductionism is relentless

Reductionism is relentless

But the forces of medicine were—and still are—driving relentlessly the other way. The science of the small and particular (reductionism), with dazzling technology and exploding subspecialty knowledge, and backed by powerful economic drivers, rewards health care for pulling the patient and the medical profession apart. We pay more to those who treat small parts of a person over a short period than to those who attend to the whole person over the lifetime.

Today, family medicine—for all of its common sense, scientific soundness, connectedness to patients, and demonstrated value—struggles to survive.^2-6 The holistic vision of Engel is declining. The struggle in primary care is that its holistic vision gets co-opted by specialized medical science—and then it desperately attempts to apply those small and specialized tools to the care of patients in their wholeness. Holism is largely dead in health care, and everyone pays the consequences.⁷

Health care is losing its value

The damage from this decline in holism is not just to primary care but to the value of health care in general. Most medical care being delivered today—comprising diagnosis, treatment, and payment (the innermost circle of the FIGURE)—is not producing good health.⁸ Only 15% to 20% of the healing of an individual or a population comes from health care.⁹ The rest—nearly 80%—comes from other factors rarely addressed in the health care system: behavioral and lifestyle choices that people make in their daily life, including those related to food, movement, sleep, stress, and substance use.¹⁰ Increasingly, it is the economic and social determinants of health that influence this behavior and have a greater impact on health and lifespan than physiology or genes.¹¹ The same social determinants of health also influence patients’ ability to obtain medical care and pursue a meaningful life.¹²

The result of this decline in holism and in the value of health care in general has been a relentless rise in the cost of medical care^13-15 and the need for social services; declining life expectancy^16,17 and quality of life¹⁸; growing patient dissatisfaction; and burnout in providers.^19,20 Health care has become, as investor and business leader Warren Buffet remarked, the “tapeworm” of the economy and a major contributor to growing disparities in health and well-being between the haves and have-nots.²¹ Engel’s prediction that good medicine cannot afford to ignore holism has come to pass.

Family medicine has allowed itself, and patients, to be picked apart by forces of reductionism and a system that profits from the sick and suffering.

3-step solution:Return to whole-person care

Family medicine needs to return to whole-person care, but it can do so only if it attends to, and effectively delivers on, the prevention, treatment, and reversal of chronic disease and the enhancement of health and well-­being. This can happen only if family medicine stops trying to be all things to all people at all times and, instead, focuses on what matters to the patient as a person.

Continue to: This means that the core...

This means that the core interaction in family medicine must be to assess the whole person—mind, body, social, spirit—and help that person make changes that improve his/her/their health and well-being based on his/her/their individualized needs and social context. In other words, family medicine needs to deliver a holistic model of APC that is person centered, relationship based, recovery focused, and paid for comprehensively.

How does one get from “standard” primary care of today (the innermost circle of the FIGURE) to a framework that truly delivers on the promise of healing? I propose 3 steps to return holism to family medicine.

STEP 1: Start with comprehensive, coordinated primary care. We know that this works. Starfield and others demonstrated this 2 decades ago, defining and devising what we know as quality primary care—characterized by first-contact care, comprehensive primary care (CPC), continuous care, and coordinated care.²² This type of primary care improves outcomes, lowers costs, and is satisfying to patients and providers.²³ The physician cares for the patient throughout that person’s entire life cycle and provides all evidence-based services needed to prevent and treat common conditions. Comprehensive primary care is positioned in the first circle outward from the innermost circle of the FIGURE.

As medicine has become increasingly complex and subspecialized, however, the ability to coordinate care is often frayed, adding cost and reducing quality.^24-26 Today, comprehensive primary care needs enhanced coordination. At a minimum, this means coordinating services for:

• chronic disease management (outpatient and inpatient transitions and emergency department use)
• referral (specialists and tests)
• pharmacy services (including delivery and patient education support).

An example of a primary care system that meets these requirements is the Catalyst Health Network in central Texas, which supplies coordination services to more than 1000 comprehensive primary care practices and 1.5 million patients.²⁷ The Catalyst Network makes money for those practices, saves money in the system, enhances patient and provider satisfaction, and improves population health in the community.²⁷ I call this enhanced primary care (EPC), shown in the second circle out from the innermost circle of the FIGURE.

STEP 2: Add integrative medicine and mental health. EPC improves fragmented care but does not necessarily address a patient’s underlying determinants of healing. We know that health behaviors such as smoking cessation, avoidance of alcohol and drug abuse, improved diet, physical activity, sleep, and stress management contribute 40% to 60% of a person’s and a population’s health.¹⁰ In addition, evidence shows that behavioral health services, along with lifestyle change support, can even reverse many chronic diseases seen in primary care, such as obesity, diabetes, hypertension, cardiovascular disease, depression, and substance abuse.^28,29

Continue to: Therefore, we need to add...

Therefore, we need to add routine mental health services and nonpharmacotherapeutic approaches (eg, complementary and alternative medicine) to primary care.³⁰ Doing so requires that behavioral change and self-care become a central feature of the ­doctor–patient dialogue and team skills³¹ and be added to primary care.^30,31 I call this integrative primary care (IPC), shown on the left side in the third circle out from the innermost circle of the FIGURE.
 

Only 15% to 20% of individual and population healing comes from health care; the rest, from behavioral and lifestyle choices rarely addressed in primary care.

An example of IPC is Whole Health, an initiative of the US Veteran’s Health Administration. Whole Health empowers and informs a person-centered approach and integrates it into the delivery of routine care.³² Evaluation of Whole Health implementation, which involved more than 130,000 veterans followed for 2 years, found a net overall reduction in the total cost of care of 20%—saving nearly $650 million or, on average, more than $4500 per veteran.³³

STEP 3: Address social determinants of health. Primary care will not fully be part of the solution for producing health and well-being unless it becomes instrumental in addressing the social determinants of health (SDH), defined as “… conditions in the environments in which people are born, live, learn, work, play, worship, and age that affect a wide range of health, functioning, and quality-of-life outcomes and risks.”³⁴ These determinants include not only basic needs, such as housing, food, safety, and transportation (ie, social needs), but also what are known as structural determinants, such as income, education, language, and racial and ethnic bias. Health care cannot solve all of these social ills,but it is increasingly being called on to be the nexus of coordination for services that address these needs when they affect health outcomes.^35,36

Examples of health systems that provide for social needs include the free “food prescription” program of Pennsylvania’s Geisinger Health System, for patients with diabetes who do not have the resources to pay for food.³⁷ This approach improves blood glucose control by patients and saves money on medications and other interventions. Similarly, Kaiser Permanente has experimented with housing vouchers for homeless patients,and most Federally Qualified Health Centers provide bus or other transportation tickets to patients for their appointments and free or discounted tests and specialty care.³⁸

Implementing whole-person care for all

I propose that we make APC the central focus of family medicine. This model would comprise CPC, plus EPC, IPC, and community coordination to address SDH. This is expressed as:

CPC + EPC + IPC + SDH = APC

Continue to: APC would mean...

APC would mean health for the whole person and for all people. Again, the FIGURE shows how this model, encompassing the entire third circle out from the center circle, could be created from current models of care.

How do we pay for this? We already do—and way too much. The problem is not lack of money in the health care system but how it is organized and distributed. The Centers for Medicare and Medicaid Services and other payers are developing value-based payment models to help cover this type of care,³⁹ but payers cannot pay for something if it is unavailable.

Can family physicians deliver APC? I believe they can, and have given a few examples here to show how this is already happening. To help primary care providers start to deliver APC in their system, my team and I have built the HOPE (Healing Oriented Practices & Environments) Note Toolkit to use in daily practice.⁴⁰ These and other tools are being used by a number of large hospital systems and health care networks around the country. (You can download the HOPE Note Toolkit, at no cost, at https://drwaynejonas.com/­resources/hope-note/.)

At a minimum, comprehensive primary care needs to coordinate services for chronic disease management, referral (to specialists and testing), and pharmacy services.

Whatever we call this new type of primary care, it needs to care for the whole person and to be available to all. It finds expression in these assertions:

• We cannot ignore an essential part of what a human being is and expect them to heal or become whole.
• We cannot ignore essential people in our communities and expect our costs to go down or our compassion to go up.
• We need to stop allowing family medicine to be co-opted by reductionism and its profits.

In sum, we need a new vision of primary care—like Engel’s holistic vision in the 1970s—to motivate us, and we need to return to fundamental concepts of how healing works in medicine.⁴¹

CORRESPONDENCE

Wayne B. Jonas, MD, Samueli Integrative Health Programs, 1800 Diagonal Road, Suite 617, Alexandria, VA 22314; wayne@drwaynejonas.com.

Insect, arachnid, and other arthropod bites and stings are common patient complaints in a primary care office. A thorough history and physical exam can often isolate the specific offender and guide management. In this article, we outline how to identify, diagnose, and treat common bites and stings from bees and wasps; centipedes and spiders; fleas; flies and biting midges; mosquitoes; and ticks, and discuss how high-risk patients should be triaged and referred for additional testing and treatment, such as venom immunotherapy (VIT).

Insects and arachnids:Background and epidemiology

Insects are arthropods with 3-part exoskeletons: head, thorax, and abdomen. They have 6 jointed legs, compound eyes, and antennae. There are approximately 91,000 insect species in the United States, the most abundant orders being Coleoptera (beetles), Diptera (flies), and Hymenoptera (includes ants, bees, wasps, and sawflies).¹

The reported incidence of insect bites and stings varies widely because most people experience mild symptoms and therefore do not seek medical care. Best statistics are for Hymenoptera stings, which are more likely to cause a severe reaction. In Europe, 56% to 94% of the general population has reported being bitten or stung by one of the Hymenoptera species.² In many areas of Australia, the incidence of jack jumper ant stings is only 2% to 3%³; in the United States, 55% of people report being stung by nonnative fire ants within 3 weeks of moving into an endemic area.⁴

Arachnids are some of the earliest terrestrial organisms, of the class Arachnida, which includes scorpions, ticks, spiders, mites, and daddy longlegs (harvestmen).⁵ Arachnids are wingless and characterized by segmented bodies, jointed appendages, and exoskeletons.^6,7 In most, the body is separated into 2 segments (the cephalothorax and abdomen), except for mites, ticks, and daddy longlegs, in which the entire body comprises a single segment.⁵

Arthropod bites are common in the United States; almost one-half are caused by spiders.⁷ Brown recluse (Loxosceles spp) and black widow (Latrodectus spp) spider bites are the most concerning: Although usually mild, these bites can be life-threatening but are rarely fatal. In 2013, almost 3500 bites by black widow and brown recluse spiders were reported.⁸

Among beekeepers, the risk of a systemic reaction is higher in those stung < 15 times a year than in those stung > 200 times.

Risk factors

Risk factors for insect, arachnid, and other arthropod bites and stings are primarily environmental. People who live or work in proximity of biting or stinging insects (eg, gardeners and beekeepers) are more likely to be affected; so are those who work with animals or live next to standing water or grassy or wooded locales.

Continue to: There are also risk factors...

There are also risk factors for a systemic sting reaction:

• A sting reaction < 2 months earlier increases the risk of a subsequent systemic sting reaction by ≥ 50%.⁹
• Among beekeepers, paradoxically, the risk of a systemic reaction is higher in those stung < 15 times a year than in those stung > 200 times.¹⁰
• Patients with an elevated baseline serum level of tryptase (reference range, < 11.4 ng/mL), which is part of the allergenic response, or with biopsy-proven systemic mastocytosis are at increased risk of a systemic sting reaction.¹¹

Presentation: Signs and symptomsvary with severity

Insect bites and stings usually cause transient local inflammation and, occasionally, a toxic reaction. Allergic hypersensitivity can result in a large local reaction or a generalized systemic reaction¹²:

• A small local reaction is transient and mild, develops directly at the site of the sting, and can last several days.¹³
• A large (or significant) local reaction, defined as swelling > 10 cm in diameter (FIGURE 1) and lasting > 24 hours, occurs in 2% to 26% of people who have been bitten or stung.¹⁴ This is an immunoglobulin (Ig) E–mediated late-phase reaction that can be accompanied by fatigue and nausea.^12,13,15 For a patient with a large local reaction, the risk of a concomitant systemic reaction is 4% to 10%, typically beginning within 30 minutes after envenomation or, possibly, delayed for several hours or marked by a biphasic interval.¹⁶
• Characteristics of a systemic reaction are urticaria, angioedema, bronchospasm, large-airway edema, hypotension, and other clinical manifestations of anaphylaxis.¹⁷ In the United States, a systemic sting reaction is reported to occur in approximately 3% of bite and sting victims. Mortality among the general population from a systemic bite or sting reaction is 0.16 for every 100,000 people,² and at least 40 to 100 die every year in the United States from anaphylaxis resulting from an insect bite or sting.¹⁸
• The most severe anaphylactic reactions involve the cardiovascular and respiratory systems, commonly including hypotension and symptoms of upper- or lower-airway obstruction. Laryngeal edema and circulatory failure are the most common mechanisms of anaphylactic death.¹⁹

Bees and wasps

Hymenoptera stinging insects include the family Apidae (honey bee, bumblebee, and sweat bee) and Vespidae (yellow jacket, yellow- and white-faced hornets, and paper wasp). A worker honey bee can sting only once, leaving its barbed stinger in the skin; a wasp, hornet, and yellow jacket can sting multiple times (FIGURE 2).²

Continue to: Bee and wasp sting...

Bee and wasp sting allergies are the most common insect venom allergic reactions. A bee sting is more likely to lead to a severe allergic reaction than a wasp sting. Allergic reactions to hornet and bumblebee stings are less common but can occur in patients already sensitized to wasp and honey bee stings.^20,21

Management. Remove honey bee stingers by scraping the skin with a fingernail or credit card. Ideally, the stinger should be removed in the first 30 seconds, before the venom sac empties. Otherwise, intense local inflammation, with possible lymphangitic streaking, can result.²²

For guidance on localized symptomatic care of bee and wasp stings and bites and stings from other sources discussed in this article, see “Providing relief and advanced care” on page E6.

Centipedes and spiders

Centipedes are arthropods of the class Chilopoda, subphylum Myriapoda, that are characterized by repeating linear (metameric) segments, each containing 1 pair of legs.²³ Centipedes have a pair of poison claws behind the head that are used to paralyze prey—usually, small insects.^23,24 The bite of a larger centipede can cause a painful reaction that generally subsides after a few hours but can last several days. Centipede bites are usually nonfatal to humans.²³

Spiders belong to the class Arachnida, order Araneae. They have 8 legs with chelicerae (mouthpiece, or “jaws”) that inject venom into prey.²⁵ Most spiders found in the United States cannot bite through human skin.^26,27 Common exceptions are black widow and brown recluse spiders, which each produce a distinct toxic venom that can cause significant morbidity in humans through a bite, although bites are rarely fatal.^26,27

The brown recluse spider is described as having a violin-shaped marking on the abdomen; the body is yellowish, tan, or dark brown. A bite can produce tiny fang marks and cause dull pain at the site of the bite that spreads quickly; myalgia; and pain in the stomach, back, chest, and legs.^28,29 The bite takes approximately 7 days to resolve. In a minority of cases, a tender erythematous halo develops, followed by a severe necrotic ulcer, or loxoscelism (FIGURE 3; 40% of cases) or scarring (13%), or both.^29,30

Continue to: In contrast...

A bee sting is more likely to lead to a severe allergic reaction than a wasp sting.

Management. Again, see “Providing relief and advanced care” on page E6. Consider providing antivenin treatment for moderate or severe bites of brown recluse and black widow spiders.

Fleas

Fleas are members of the order Siphonaptera. They are small (1.5-3.2 mm long), reddish brown, wingless, blood-sucking insects with long legs that allow them to jump far (12 or 13 inches) and high (6 or 7 inches).³³ Domesticated cats and dogs are the source of most flea infestations, resulting in an increased risk of exposure for humans.^34,35 Flea bites, which generally occur on lower extremities, develop into a small, erythematous papule with a halo (FIGURE 4) and associated mild edema, and cause intense pruritus 30 minutes after the bite.^35-37

Fleas are a vector for severe microbial infections, including bartonellosis, bubonic plague, cat-flea typhus, murine typhus, cat-scratch disease, rickettsial disease, and tularemia. Tungiasis is an inflammatory burrowing flea infestation—not a secondary infection for which the flea is a vector.^34,35

Preventive management. Repellents, including products that contain DEET (N,N-diethyl-meta-toluamide), picaridin (2-[2-hydroxyethyl]-1-piperidinecarboxylic acid 1-methylpropyl ester), and PMD (p-menthane-3,8-diol, a chemical constituent of Eucalyptus citriodora oil) can be used to prevent flea bites in humans.^33,38 Studies show that the scent of other botanic oils, including lavender, cedarwood, and peppermint, can also help prevent infestation by fleas; however, these compounds are not as effective as traditional insect repellents.^33,38

Flea control is difficult, requiring a multimodal approach to treating the infested animal and its environment.³⁹ Treatment of the infested domestic animal is the primary method of preventing human bites. Nonpesticidal control involves frequent cleaning of carpeting, furniture, animal bedding, and kennels. Insecticides can be applied throughout the house to combat severe infestation.^33,38

Continue to: The Centers for Disease Control and Prevention...

Flies and biting midges

Flies are 2-winged insects belonging to the order Diptera. Several fly species can bite, causing a local inflammatory reaction; these include black flies, deer flies, horse flies, and sand flies. Signs and symptoms of a fly bite include pain, pruritus, erythema, and mild swelling (FIGURE 5).^41,42 Flies can transmit several infections, including bartonellosis, enteric bacterial disease (eg, caused by Campylobacter spp), leishmaniasis, loiasis, onchocerciasis, and trypanosomiasis.⁴³

Biting midges, also called “no-see-ums,” biting gnats, moose flies, and “punkies,”⁴⁴ are tiny (1-3 mm long) blood-sucking flies.⁴⁵ Bitten patients often report not having seen the midge because it is so small. The bite typically starts as a small, erythematous papule that develops into a dome-shaped blister and can be extraordinarily pruritic and painful.⁴⁴ The majority of people who have been bitten develop a hypersensitivity reaction, which usually resolves in a few weeks.

Management. Suppressing adult biting midges with an environmental insecticide is typically insufficient because the insecticide must be sprayed daily to eradicate active midges and generally does not affect larval habitat. Insect repellents and biopesticides, such as oil of lemon eucalyptus, can be effective in reducing the risk of bites.^44,45

Mosquitoes

Mosquitoes are flying, blood-sucking insects of the order Diptera and family Culicidae. Anopheles, Culex, and Aedes genera are responsible for most bites of humans.

Most spiders found in the United States can’t bite through human skin. Common exceptions are black widow and brown recluse spiders.

The bite of a mosquito produces an indurated, limited local reaction characterized by a pruritic wheal (3-29 mm in diameter) with surrounding erythema (FIGURE 6) that peaks in approximately 30 minutes, although patients might have a delayed reaction hours later.⁴⁶ Immunocompromised patients might experience a more significant local inflammatory reaction that is accompanied by low-grade fever, hives, or swollen lymph nodes.^46,47

Mosquitoes are a vector for serious infections, including dengue, Japanese encephalitis, malaria, and yellow fever, and disease caused by Chikungunya, West Nile, and Zika viruses.

Continue to: Management

Ticks

Ticks belong to the order Parasitiformes and families Ixodidae and Argasidae. Hard ticks are found in brushy fields and tall grasses and can bite and feed on humans for days. Soft ticks are generally found around animal nests.²⁹ Tick bites can cause a local reaction that includes painful, erythematous, inflammatory papular lesions (FIGURE 7).⁴⁹

Ticks can transmit several infectious diseases. Depending on the microbial pathogen and the genus and species of tick, it takes 2 to 96 hours for the tick to attach to skin and transmit the pathogen to the human host. The TABLE^29,49,50 provides an overview of tick species in the United States, diseases that they can transmit, and the geographic distribution of those diseases.

Management. Ticks should be removed with fine-tipped tweezers. Grasp the body of the tick close to the skin and pull upward while applying steady, even pressure. After removing the tick, clean the bite and the surrounding area with alcohol or with soap and water. Dispose of a live tick by flushing it down the toilet; or, kill it in alcohol and either seal it in a bag with tape or place it in a container.⁵⁰

Diagnosis and the utilityof special testing

The diagnosis of insect, arachnid, and other arthropod bites and stings depends on the history, including obtaining a record of possible exposure and a travel history; the timing of the bite or sting; and associated signs and symptoms.^18,51

Venom skin testing. For Hymenoptera stings, intradermal tests using a venom concentration of 0.001 to 1 μg/mL are positive in 65% to 80% of patients with a history of a systemic insect-sting allergic reaction. A negative venom skin test can occur during the 3-to-6-week refractory period after a sting reaction or many years later, which represents a loss of sensitivity. Positive venom skin tests are used to confirm allergy and identify specific insects to which the patient is allergic.^11,12

Continue to: Allergen-specific IgE antibody testing.

Providing reliefand advanced care

Symptomatic treatment of mild bites and stings includes washing the affected area with soap and water and applying a cold compress to reduce swelling.⁵⁴ For painful lesions, an oral analgesic can be prescribed.

For mild or moderate pruritus, a low- to midpotency topical corticosteroid (eg, hydrocortisone valerate cream 0.2% bid), topical calamine, or pramoxine can be applied,or a nonsedating oral antihistamine, such as loratadine (10 mg/d) or cetirizine (10 mg/d), can be used.^14,55 For severe itching, a sedating antihistamine, such as hydroxyzine (10-25 mg every 4 to 6 hours prn), might help relieve symptoms; H₁- and H₂-receptor antagonists can be used concomitantly.^54,55

Significant local symptoms. Large local reactions are treated with a midpotency topical corticosteroid (eg, triamcinolone acetonide cream 0.1% bid) plus an oral antihistamine to relieve pruritus and reduce allergic inflammation. For a more severe reaction, an oral corticosteroid (prednisone 1 mg/kg; maximum dosage, 50 mg/d) can be given for 5 to 7 days.^54-56

Management of a necrotic ulcer secondary to a brown recluse spider bite is symptomatic and supportive. The size of these wounds can increase for as long as 10 days after the bite; resolution can require months of wound care, possibly with debridement. Rarely, skin grafting is required.^27,28,31

VIT. Some studies show that VIT can improve quality of life in patients with prolonged, frequent, and worsening reactions to insect bites or stings and repeated, unavoidable exposures.^55,56 VIT is recommended for patients with systemic hypersensitivity and a positive venom skin test result. It is approximately 95% effective in preventing or reducing severe systemic reactions and reduces the risk of anaphylaxis (see next section) and death.⁵⁷ The maintenance dosage of VIT is usually 100 μg every 4 to 6 weeks; optimal duration of treatment is 3 to 5 years.⁵⁸

Continue to: After VIT is complete...

• a history of severe, life-threatening allergic reactions to bites and stings
• honey bee sting allergy
• mast-cell disease
• a history of anaphylaxis while receiving VIT.

Absolute contraindications to VIT include a history of serious immune disease, chronic infection, or cancer.^58,59

Managing anaphylaxis

This severe allergic reaction can lead to death if untreated. First-line therapy is intramuscular epinephrine, 0.01 mg/kg (maximum single dose, 0.5 mg) given every 5 to 15 minutes.^14,60 Epinephrine auto-injectors deliver a fixed dose and are labeled according to weight. Administration of O₂ and intravenous fluids is recommended for hemodynamically unstable patients.^60,61 Antihistamines and corticosteroids can be used as secondary treatment but should not replace epinephrine.⁵⁶

After preliminary improvement, patients might decompensate when the epinephrine dose wears off. Furthermore, a biphasic reaction, variously reported in < 5% to as many as 20% of patients,^61,62 occurs hours after the initial anaphylactic reaction. Patients should be monitored, therefore, for at least 6 to 8 hours after an anaphylactic reaction, preferably in a facility equipped to treat anaphylaxis.^17,56
 

The scent of botanic oils, including lavender and peppermint, can help prevent infestation by fleas.

Before discharge, patients who have had an anaphylactic reaction should be given a prescription for epinephrine and training in the use of an epinephrine auto-injector. Allergen avoidance, along with an emergency plan in the event of a bite or sting, is recommended. Follow-up evaluation with an allergist or immunologist is essential for proper diagnosis and to determine whether the patient is a candidate for VIT.^14,17

CORRESPONDENCE
Ecler Ercole Jaqua, MD, DipABLM, FAAFP, 1200 California Street, Suite 240, Redlands, CA 92374; ejaqua@llu.edu.

Insect, arachnid, and other arthropod bites and stings are common patient complaints in a primary care office. A thorough history and physical exam can often isolate the specific offender and guide management. In this article, we outline how to identify, diagnose, and treat common bites and stings from bees and wasps; centipedes and spiders; fleas; flies and biting midges; mosquitoes; and ticks, and discuss how high-risk patients should be triaged and referred for additional testing and treatment, such as venom immunotherapy (VIT).

Insects and arachnids:Background and epidemiology

Insects are arthropods with 3-part exoskeletons: head, thorax, and abdomen. They have 6 jointed legs, compound eyes, and antennae. There are approximately 91,000 insect species in the United States, the most abundant orders being Coleoptera (beetles), Diptera (flies), and Hymenoptera (includes ants, bees, wasps, and sawflies).¹

The reported incidence of insect bites and stings varies widely because most people experience mild symptoms and therefore do not seek medical care. Best statistics are for Hymenoptera stings, which are more likely to cause a severe reaction. In Europe, 56% to 94% of the general population has reported being bitten or stung by one of the Hymenoptera species.² In many areas of Australia, the incidence of jack jumper ant stings is only 2% to 3%³; in the United States, 55% of people report being stung by nonnative fire ants within 3 weeks of moving into an endemic area.⁴

Arachnids are some of the earliest terrestrial organisms, of the class Arachnida, which includes scorpions, ticks, spiders, mites, and daddy longlegs (harvestmen).⁵ Arachnids are wingless and characterized by segmented bodies, jointed appendages, and exoskeletons.^6,7 In most, the body is separated into 2 segments (the cephalothorax and abdomen), except for mites, ticks, and daddy longlegs, in which the entire body comprises a single segment.⁵

Arthropod bites are common in the United States; almost one-half are caused by spiders.⁷ Brown recluse (Loxosceles spp) and black widow (Latrodectus spp) spider bites are the most concerning: Although usually mild, these bites can be life-threatening but are rarely fatal. In 2013, almost 3500 bites by black widow and brown recluse spiders were reported.⁸

Among beekeepers, the risk of a systemic reaction is higher in those stung < 15 times a year than in those stung > 200 times.

Risk factors

Risk factors for insect, arachnid, and other arthropod bites and stings are primarily environmental. People who live or work in proximity of biting or stinging insects (eg, gardeners and beekeepers) are more likely to be affected; so are those who work with animals or live next to standing water or grassy or wooded locales.

Continue to: There are also risk factors...

There are also risk factors for a systemic sting reaction:

• A sting reaction < 2 months earlier increases the risk of a subsequent systemic sting reaction by ≥ 50%.⁹
• Among beekeepers, paradoxically, the risk of a systemic reaction is higher in those stung < 15 times a year than in those stung > 200 times.¹⁰
• Patients with an elevated baseline serum level of tryptase (reference range, < 11.4 ng/mL), which is part of the allergenic response, or with biopsy-proven systemic mastocytosis are at increased risk of a systemic sting reaction.¹¹

Presentation: Signs and symptomsvary with severity

Insect bites and stings usually cause transient local inflammation and, occasionally, a toxic reaction. Allergic hypersensitivity can result in a large local reaction or a generalized systemic reaction¹²:

• A small local reaction is transient and mild, develops directly at the site of the sting, and can last several days.¹³
• A large (or significant) local reaction, defined as swelling > 10 cm in diameter (FIGURE 1) and lasting > 24 hours, occurs in 2% to 26% of people who have been bitten or stung.¹⁴ This is an immunoglobulin (Ig) E–mediated late-phase reaction that can be accompanied by fatigue and nausea.^12,13,15 For a patient with a large local reaction, the risk of a concomitant systemic reaction is 4% to 10%, typically beginning within 30 minutes after envenomation or, possibly, delayed for several hours or marked by a biphasic interval.¹⁶
• Characteristics of a systemic reaction are urticaria, angioedema, bronchospasm, large-airway edema, hypotension, and other clinical manifestations of anaphylaxis.¹⁷ In the United States, a systemic sting reaction is reported to occur in approximately 3% of bite and sting victims. Mortality among the general population from a systemic bite or sting reaction is 0.16 for every 100,000 people,² and at least 40 to 100 die every year in the United States from anaphylaxis resulting from an insect bite or sting.¹⁸
• The most severe anaphylactic reactions involve the cardiovascular and respiratory systems, commonly including hypotension and symptoms of upper- or lower-airway obstruction. Laryngeal edema and circulatory failure are the most common mechanisms of anaphylactic death.¹⁹

Bees and wasps

Hymenoptera stinging insects include the family Apidae (honey bee, bumblebee, and sweat bee) and Vespidae (yellow jacket, yellow- and white-faced hornets, and paper wasp). A worker honey bee can sting only once, leaving its barbed stinger in the skin; a wasp, hornet, and yellow jacket can sting multiple times (FIGURE 2).²

Continue to: Bee and wasp sting...

Bee and wasp sting allergies are the most common insect venom allergic reactions. A bee sting is more likely to lead to a severe allergic reaction than a wasp sting. Allergic reactions to hornet and bumblebee stings are less common but can occur in patients already sensitized to wasp and honey bee stings.^20,21

Management. Remove honey bee stingers by scraping the skin with a fingernail or credit card. Ideally, the stinger should be removed in the first 30 seconds, before the venom sac empties. Otherwise, intense local inflammation, with possible lymphangitic streaking, can result.²²

For guidance on localized symptomatic care of bee and wasp stings and bites and stings from other sources discussed in this article, see “Providing relief and advanced care” on page E6.

Centipedes and spiders

Centipedes are arthropods of the class Chilopoda, subphylum Myriapoda, that are characterized by repeating linear (metameric) segments, each containing 1 pair of legs.²³ Centipedes have a pair of poison claws behind the head that are used to paralyze prey—usually, small insects.^23,24 The bite of a larger centipede can cause a painful reaction that generally subsides after a few hours but can last several days. Centipede bites are usually nonfatal to humans.²³

Spiders belong to the class Arachnida, order Araneae. They have 8 legs with chelicerae (mouthpiece, or “jaws”) that inject venom into prey.²⁵ Most spiders found in the United States cannot bite through human skin.^26,27 Common exceptions are black widow and brown recluse spiders, which each produce a distinct toxic venom that can cause significant morbidity in humans through a bite, although bites are rarely fatal.^26,27

The brown recluse spider is described as having a violin-shaped marking on the abdomen; the body is yellowish, tan, or dark brown. A bite can produce tiny fang marks and cause dull pain at the site of the bite that spreads quickly; myalgia; and pain in the stomach, back, chest, and legs.^28,29 The bite takes approximately 7 days to resolve. In a minority of cases, a tender erythematous halo develops, followed by a severe necrotic ulcer, or loxoscelism (FIGURE 3; 40% of cases) or scarring (13%), or both.^29,30

Continue to: In contrast...

A bee sting is more likely to lead to a severe allergic reaction than a wasp sting.

Management. Again, see “Providing relief and advanced care” on page E6. Consider providing antivenin treatment for moderate or severe bites of brown recluse and black widow spiders.

Fleas

Fleas are members of the order Siphonaptera. They are small (1.5-3.2 mm long), reddish brown, wingless, blood-sucking insects with long legs that allow them to jump far (12 or 13 inches) and high (6 or 7 inches).³³ Domesticated cats and dogs are the source of most flea infestations, resulting in an increased risk of exposure for humans.^34,35 Flea bites, which generally occur on lower extremities, develop into a small, erythematous papule with a halo (FIGURE 4) and associated mild edema, and cause intense pruritus 30 minutes after the bite.^35-37

Fleas are a vector for severe microbial infections, including bartonellosis, bubonic plague, cat-flea typhus, murine typhus, cat-scratch disease, rickettsial disease, and tularemia. Tungiasis is an inflammatory burrowing flea infestation—not a secondary infection for which the flea is a vector.^34,35

Preventive management. Repellents, including products that contain DEET (N,N-diethyl-meta-toluamide), picaridin (2-[2-hydroxyethyl]-1-piperidinecarboxylic acid 1-methylpropyl ester), and PMD (p-menthane-3,8-diol, a chemical constituent of Eucalyptus citriodora oil) can be used to prevent flea bites in humans.^33,38 Studies show that the scent of other botanic oils, including lavender, cedarwood, and peppermint, can also help prevent infestation by fleas; however, these compounds are not as effective as traditional insect repellents.^33,38

Flea control is difficult, requiring a multimodal approach to treating the infested animal and its environment.³⁹ Treatment of the infested domestic animal is the primary method of preventing human bites. Nonpesticidal control involves frequent cleaning of carpeting, furniture, animal bedding, and kennels. Insecticides can be applied throughout the house to combat severe infestation.^33,38

Continue to: The Centers for Disease Control and Prevention...

Flies and biting midges

Flies are 2-winged insects belonging to the order Diptera. Several fly species can bite, causing a local inflammatory reaction; these include black flies, deer flies, horse flies, and sand flies. Signs and symptoms of a fly bite include pain, pruritus, erythema, and mild swelling (FIGURE 5).^41,42 Flies can transmit several infections, including bartonellosis, enteric bacterial disease (eg, caused by Campylobacter spp), leishmaniasis, loiasis, onchocerciasis, and trypanosomiasis.⁴³

Biting midges, also called “no-see-ums,” biting gnats, moose flies, and “punkies,”⁴⁴ are tiny (1-3 mm long) blood-sucking flies.⁴⁵ Bitten patients often report not having seen the midge because it is so small. The bite typically starts as a small, erythematous papule that develops into a dome-shaped blister and can be extraordinarily pruritic and painful.⁴⁴ The majority of people who have been bitten develop a hypersensitivity reaction, which usually resolves in a few weeks.

Management. Suppressing adult biting midges with an environmental insecticide is typically insufficient because the insecticide must be sprayed daily to eradicate active midges and generally does not affect larval habitat. Insect repellents and biopesticides, such as oil of lemon eucalyptus, can be effective in reducing the risk of bites.^44,45

Mosquitoes

Mosquitoes are flying, blood-sucking insects of the order Diptera and family Culicidae. Anopheles, Culex, and Aedes genera are responsible for most bites of humans.

Most spiders found in the United States can’t bite through human skin. Common exceptions are black widow and brown recluse spiders.

The bite of a mosquito produces an indurated, limited local reaction characterized by a pruritic wheal (3-29 mm in diameter) with surrounding erythema (FIGURE 6) that peaks in approximately 30 minutes, although patients might have a delayed reaction hours later.⁴⁶ Immunocompromised patients might experience a more significant local inflammatory reaction that is accompanied by low-grade fever, hives, or swollen lymph nodes.^46,47

Mosquitoes are a vector for serious infections, including dengue, Japanese encephalitis, malaria, and yellow fever, and disease caused by Chikungunya, West Nile, and Zika viruses.

Continue to: Management

Ticks

Ticks belong to the order Parasitiformes and families Ixodidae and Argasidae. Hard ticks are found in brushy fields and tall grasses and can bite and feed on humans for days. Soft ticks are generally found around animal nests.²⁹ Tick bites can cause a local reaction that includes painful, erythematous, inflammatory papular lesions (FIGURE 7).⁴⁹

Ticks can transmit several infectious diseases. Depending on the microbial pathogen and the genus and species of tick, it takes 2 to 96 hours for the tick to attach to skin and transmit the pathogen to the human host. The TABLE^29,49,50 provides an overview of tick species in the United States, diseases that they can transmit, and the geographic distribution of those diseases.

Management. Ticks should be removed with fine-tipped tweezers. Grasp the body of the tick close to the skin and pull upward while applying steady, even pressure. After removing the tick, clean the bite and the surrounding area with alcohol or with soap and water. Dispose of a live tick by flushing it down the toilet; or, kill it in alcohol and either seal it in a bag with tape or place it in a container.⁵⁰

Diagnosis and the utilityof special testing

The diagnosis of insect, arachnid, and other arthropod bites and stings depends on the history, including obtaining a record of possible exposure and a travel history; the timing of the bite or sting; and associated signs and symptoms.^18,51

Venom skin testing. For Hymenoptera stings, intradermal tests using a venom concentration of 0.001 to 1 μg/mL are positive in 65% to 80% of patients with a history of a systemic insect-sting allergic reaction. A negative venom skin test can occur during the 3-to-6-week refractory period after a sting reaction or many years later, which represents a loss of sensitivity. Positive venom skin tests are used to confirm allergy and identify specific insects to which the patient is allergic.^11,12

Continue to: Allergen-specific IgE antibody testing.

Providing reliefand advanced care

Symptomatic treatment of mild bites and stings includes washing the affected area with soap and water and applying a cold compress to reduce swelling.⁵⁴ For painful lesions, an oral analgesic can be prescribed.

For mild or moderate pruritus, a low- to midpotency topical corticosteroid (eg, hydrocortisone valerate cream 0.2% bid), topical calamine, or pramoxine can be applied,or a nonsedating oral antihistamine, such as loratadine (10 mg/d) or cetirizine (10 mg/d), can be used.^14,55 For severe itching, a sedating antihistamine, such as hydroxyzine (10-25 mg every 4 to 6 hours prn), might help relieve symptoms; H₁- and H₂-receptor antagonists can be used concomitantly.^54,55

Significant local symptoms. Large local reactions are treated with a midpotency topical corticosteroid (eg, triamcinolone acetonide cream 0.1% bid) plus an oral antihistamine to relieve pruritus and reduce allergic inflammation. For a more severe reaction, an oral corticosteroid (prednisone 1 mg/kg; maximum dosage, 50 mg/d) can be given for 5 to 7 days.^54-56

Management of a necrotic ulcer secondary to a brown recluse spider bite is symptomatic and supportive. The size of these wounds can increase for as long as 10 days after the bite; resolution can require months of wound care, possibly with debridement. Rarely, skin grafting is required.^27,28,31

VIT. Some studies show that VIT can improve quality of life in patients with prolonged, frequent, and worsening reactions to insect bites or stings and repeated, unavoidable exposures.^55,56 VIT is recommended for patients with systemic hypersensitivity and a positive venom skin test result. It is approximately 95% effective in preventing or reducing severe systemic reactions and reduces the risk of anaphylaxis (see next section) and death.⁵⁷ The maintenance dosage of VIT is usually 100 μg every 4 to 6 weeks; optimal duration of treatment is 3 to 5 years.⁵⁸

Continue to: After VIT is complete...

• a history of severe, life-threatening allergic reactions to bites and stings
• honey bee sting allergy
• mast-cell disease
• a history of anaphylaxis while receiving VIT.

Absolute contraindications to VIT include a history of serious immune disease, chronic infection, or cancer.^58,59

Managing anaphylaxis

This severe allergic reaction can lead to death if untreated. First-line therapy is intramuscular epinephrine, 0.01 mg/kg (maximum single dose, 0.5 mg) given every 5 to 15 minutes.^14,60 Epinephrine auto-injectors deliver a fixed dose and are labeled according to weight. Administration of O₂ and intravenous fluids is recommended for hemodynamically unstable patients.^60,61 Antihistamines and corticosteroids can be used as secondary treatment but should not replace epinephrine.⁵⁶

After preliminary improvement, patients might decompensate when the epinephrine dose wears off. Furthermore, a biphasic reaction, variously reported in < 5% to as many as 20% of patients,^61,62 occurs hours after the initial anaphylactic reaction. Patients should be monitored, therefore, for at least 6 to 8 hours after an anaphylactic reaction, preferably in a facility equipped to treat anaphylaxis.^17,56
 

The scent of botanic oils, including lavender and peppermint, can help prevent infestation by fleas.

Before discharge, patients who have had an anaphylactic reaction should be given a prescription for epinephrine and training in the use of an epinephrine auto-injector. Allergen avoidance, along with an emergency plan in the event of a bite or sting, is recommended. Follow-up evaluation with an allergist or immunologist is essential for proper diagnosis and to determine whether the patient is a candidate for VIT.^14,17

CORRESPONDENCE
Ecler Ercole Jaqua, MD, DipABLM, FAAFP, 1200 California Street, Suite 240, Redlands, CA 92374; ejaqua@llu.edu.

Insect, arachnid, and other arthropod bites and stings are common patient complaints in a primary care office. A thorough history and physical exam can often isolate the specific offender and guide management. In this article, we outline how to identify, diagnose, and treat common bites and stings from bees and wasps; centipedes and spiders; fleas; flies and biting midges; mosquitoes; and ticks, and discuss how high-risk patients should be triaged and referred for additional testing and treatment, such as venom immunotherapy (VIT).

Insects and arachnids:Background and epidemiology

Insects are arthropods with 3-part exoskeletons: head, thorax, and abdomen. They have 6 jointed legs, compound eyes, and antennae. There are approximately 91,000 insect species in the United States, the most abundant orders being Coleoptera (beetles), Diptera (flies), and Hymenoptera (includes ants, bees, wasps, and sawflies).¹

The reported incidence of insect bites and stings varies widely because most people experience mild symptoms and therefore do not seek medical care. Best statistics are for Hymenoptera stings, which are more likely to cause a severe reaction. In Europe, 56% to 94% of the general population has reported being bitten or stung by one of the Hymenoptera species.² In many areas of Australia, the incidence of jack jumper ant stings is only 2% to 3%³; in the United States, 55% of people report being stung by nonnative fire ants within 3 weeks of moving into an endemic area.⁴

Arachnids are some of the earliest terrestrial organisms, of the class Arachnida, which includes scorpions, ticks, spiders, mites, and daddy longlegs (harvestmen).⁵ Arachnids are wingless and characterized by segmented bodies, jointed appendages, and exoskeletons.^6,7 In most, the body is separated into 2 segments (the cephalothorax and abdomen), except for mites, ticks, and daddy longlegs, in which the entire body comprises a single segment.⁵

Arthropod bites are common in the United States; almost one-half are caused by spiders.⁷ Brown recluse (Loxosceles spp) and black widow (Latrodectus spp) spider bites are the most concerning: Although usually mild, these bites can be life-threatening but are rarely fatal. In 2013, almost 3500 bites by black widow and brown recluse spiders were reported.⁸

Among beekeepers, the risk of a systemic reaction is higher in those stung < 15 times a year than in those stung > 200 times.

Risk factors

Risk factors for insect, arachnid, and other arthropod bites and stings are primarily environmental. People who live or work in proximity of biting or stinging insects (eg, gardeners and beekeepers) are more likely to be affected; so are those who work with animals or live next to standing water or grassy or wooded locales.

Continue to: There are also risk factors...

There are also risk factors for a systemic sting reaction:

• A sting reaction < 2 months earlier increases the risk of a subsequent systemic sting reaction by ≥ 50%.⁹
• Among beekeepers, paradoxically, the risk of a systemic reaction is higher in those stung < 15 times a year than in those stung > 200 times.¹⁰
• Patients with an elevated baseline serum level of tryptase (reference range, < 11.4 ng/mL), which is part of the allergenic response, or with biopsy-proven systemic mastocytosis are at increased risk of a systemic sting reaction.¹¹

Presentation: Signs and symptomsvary with severity

Insect bites and stings usually cause transient local inflammation and, occasionally, a toxic reaction. Allergic hypersensitivity can result in a large local reaction or a generalized systemic reaction¹²:

• A small local reaction is transient and mild, develops directly at the site of the sting, and can last several days.¹³
• A large (or significant) local reaction, defined as swelling > 10 cm in diameter (FIGURE 1) and lasting > 24 hours, occurs in 2% to 26% of people who have been bitten or stung.¹⁴ This is an immunoglobulin (Ig) E–mediated late-phase reaction that can be accompanied by fatigue and nausea.^12,13,15 For a patient with a large local reaction, the risk of a concomitant systemic reaction is 4% to 10%, typically beginning within 30 minutes after envenomation or, possibly, delayed for several hours or marked by a biphasic interval.¹⁶
• Characteristics of a systemic reaction are urticaria, angioedema, bronchospasm, large-airway edema, hypotension, and other clinical manifestations of anaphylaxis.¹⁷ In the United States, a systemic sting reaction is reported to occur in approximately 3% of bite and sting victims. Mortality among the general population from a systemic bite or sting reaction is 0.16 for every 100,000 people,² and at least 40 to 100 die every year in the United States from anaphylaxis resulting from an insect bite or sting.¹⁸
• The most severe anaphylactic reactions involve the cardiovascular and respiratory systems, commonly including hypotension and symptoms of upper- or lower-airway obstruction. Laryngeal edema and circulatory failure are the most common mechanisms of anaphylactic death.¹⁹

Bees and wasps

Hymenoptera stinging insects include the family Apidae (honey bee, bumblebee, and sweat bee) and Vespidae (yellow jacket, yellow- and white-faced hornets, and paper wasp). A worker honey bee can sting only once, leaving its barbed stinger in the skin; a wasp, hornet, and yellow jacket can sting multiple times (FIGURE 2).²

Continue to: Bee and wasp sting...

Bee and wasp sting allergies are the most common insect venom allergic reactions. A bee sting is more likely to lead to a severe allergic reaction than a wasp sting. Allergic reactions to hornet and bumblebee stings are less common but can occur in patients already sensitized to wasp and honey bee stings.^20,21

Management. Remove honey bee stingers by scraping the skin with a fingernail or credit card. Ideally, the stinger should be removed in the first 30 seconds, before the venom sac empties. Otherwise, intense local inflammation, with possible lymphangitic streaking, can result.²²

For guidance on localized symptomatic care of bee and wasp stings and bites and stings from other sources discussed in this article, see “Providing relief and advanced care” on page E6.

Centipedes and spiders

Centipedes are arthropods of the class Chilopoda, subphylum Myriapoda, that are characterized by repeating linear (metameric) segments, each containing 1 pair of legs.²³ Centipedes have a pair of poison claws behind the head that are used to paralyze prey—usually, small insects.^23,24 The bite of a larger centipede can cause a painful reaction that generally subsides after a few hours but can last several days. Centipede bites are usually nonfatal to humans.²³

Spiders belong to the class Arachnida, order Araneae. They have 8 legs with chelicerae (mouthpiece, or “jaws”) that inject venom into prey.²⁵ Most spiders found in the United States cannot bite through human skin.^26,27 Common exceptions are black widow and brown recluse spiders, which each produce a distinct toxic venom that can cause significant morbidity in humans through a bite, although bites are rarely fatal.^26,27

The brown recluse spider is described as having a violin-shaped marking on the abdomen; the body is yellowish, tan, or dark brown. A bite can produce tiny fang marks and cause dull pain at the site of the bite that spreads quickly; myalgia; and pain in the stomach, back, chest, and legs.^28,29 The bite takes approximately 7 days to resolve. In a minority of cases, a tender erythematous halo develops, followed by a severe necrotic ulcer, or loxoscelism (FIGURE 3; 40% of cases) or scarring (13%), or both.^29,30

Continue to: In contrast...

A bee sting is more likely to lead to a severe allergic reaction than a wasp sting.

Management. Again, see “Providing relief and advanced care” on page E6. Consider providing antivenin treatment for moderate or severe bites of brown recluse and black widow spiders.

Fleas

Fleas are members of the order Siphonaptera. They are small (1.5-3.2 mm long), reddish brown, wingless, blood-sucking insects with long legs that allow them to jump far (12 or 13 inches) and high (6 or 7 inches).³³ Domesticated cats and dogs are the source of most flea infestations, resulting in an increased risk of exposure for humans.^34,35 Flea bites, which generally occur on lower extremities, develop into a small, erythematous papule with a halo (FIGURE 4) and associated mild edema, and cause intense pruritus 30 minutes after the bite.^35-37

Fleas are a vector for severe microbial infections, including bartonellosis, bubonic plague, cat-flea typhus, murine typhus, cat-scratch disease, rickettsial disease, and tularemia. Tungiasis is an inflammatory burrowing flea infestation—not a secondary infection for which the flea is a vector.^34,35

Preventive management. Repellents, including products that contain DEET (N,N-diethyl-meta-toluamide), picaridin (2-[2-hydroxyethyl]-1-piperidinecarboxylic acid 1-methylpropyl ester), and PMD (p-menthane-3,8-diol, a chemical constituent of Eucalyptus citriodora oil) can be used to prevent flea bites in humans.^33,38 Studies show that the scent of other botanic oils, including lavender, cedarwood, and peppermint, can also help prevent infestation by fleas; however, these compounds are not as effective as traditional insect repellents.^33,38

Flea control is difficult, requiring a multimodal approach to treating the infested animal and its environment.³⁹ Treatment of the infested domestic animal is the primary method of preventing human bites. Nonpesticidal control involves frequent cleaning of carpeting, furniture, animal bedding, and kennels. Insecticides can be applied throughout the house to combat severe infestation.^33,38

Continue to: The Centers for Disease Control and Prevention...

Flies and biting midges

Flies are 2-winged insects belonging to the order Diptera. Several fly species can bite, causing a local inflammatory reaction; these include black flies, deer flies, horse flies, and sand flies. Signs and symptoms of a fly bite include pain, pruritus, erythema, and mild swelling (FIGURE 5).^41,42 Flies can transmit several infections, including bartonellosis, enteric bacterial disease (eg, caused by Campylobacter spp), leishmaniasis, loiasis, onchocerciasis, and trypanosomiasis.⁴³

Biting midges, also called “no-see-ums,” biting gnats, moose flies, and “punkies,”⁴⁴ are tiny (1-3 mm long) blood-sucking flies.⁴⁵ Bitten patients often report not having seen the midge because it is so small. The bite typically starts as a small, erythematous papule that develops into a dome-shaped blister and can be extraordinarily pruritic and painful.⁴⁴ The majority of people who have been bitten develop a hypersensitivity reaction, which usually resolves in a few weeks.

Management. Suppressing adult biting midges with an environmental insecticide is typically insufficient because the insecticide must be sprayed daily to eradicate active midges and generally does not affect larval habitat. Insect repellents and biopesticides, such as oil of lemon eucalyptus, can be effective in reducing the risk of bites.^44,45

Mosquitoes

Mosquitoes are flying, blood-sucking insects of the order Diptera and family Culicidae. Anopheles, Culex, and Aedes genera are responsible for most bites of humans.

Most spiders found in the United States can’t bite through human skin. Common exceptions are black widow and brown recluse spiders.

The bite of a mosquito produces an indurated, limited local reaction characterized by a pruritic wheal (3-29 mm in diameter) with surrounding erythema (FIGURE 6) that peaks in approximately 30 minutes, although patients might have a delayed reaction hours later.⁴⁶ Immunocompromised patients might experience a more significant local inflammatory reaction that is accompanied by low-grade fever, hives, or swollen lymph nodes.^46,47

Mosquitoes are a vector for serious infections, including dengue, Japanese encephalitis, malaria, and yellow fever, and disease caused by Chikungunya, West Nile, and Zika viruses.

Continue to: Management

Ticks

Ticks belong to the order Parasitiformes and families Ixodidae and Argasidae. Hard ticks are found in brushy fields and tall grasses and can bite and feed on humans for days. Soft ticks are generally found around animal nests.²⁹ Tick bites can cause a local reaction that includes painful, erythematous, inflammatory papular lesions (FIGURE 7).⁴⁹

Ticks can transmit several infectious diseases. Depending on the microbial pathogen and the genus and species of tick, it takes 2 to 96 hours for the tick to attach to skin and transmit the pathogen to the human host. The TABLE^29,49,50 provides an overview of tick species in the United States, diseases that they can transmit, and the geographic distribution of those diseases.

Management. Ticks should be removed with fine-tipped tweezers. Grasp the body of the tick close to the skin and pull upward while applying steady, even pressure. After removing the tick, clean the bite and the surrounding area with alcohol or with soap and water. Dispose of a live tick by flushing it down the toilet; or, kill it in alcohol and either seal it in a bag with tape or place it in a container.⁵⁰

Diagnosis and the utilityof special testing

The diagnosis of insect, arachnid, and other arthropod bites and stings depends on the history, including obtaining a record of possible exposure and a travel history; the timing of the bite or sting; and associated signs and symptoms.^18,51

Venom skin testing. For Hymenoptera stings, intradermal tests using a venom concentration of 0.001 to 1 μg/mL are positive in 65% to 80% of patients with a history of a systemic insect-sting allergic reaction. A negative venom skin test can occur during the 3-to-6-week refractory period after a sting reaction or many years later, which represents a loss of sensitivity. Positive venom skin tests are used to confirm allergy and identify specific insects to which the patient is allergic.^11,12

Continue to: Allergen-specific IgE antibody testing.

Providing reliefand advanced care

Symptomatic treatment of mild bites and stings includes washing the affected area with soap and water and applying a cold compress to reduce swelling.⁵⁴ For painful lesions, an oral analgesic can be prescribed.

For mild or moderate pruritus, a low- to midpotency topical corticosteroid (eg, hydrocortisone valerate cream 0.2% bid), topical calamine, or pramoxine can be applied,or a nonsedating oral antihistamine, such as loratadine (10 mg/d) or cetirizine (10 mg/d), can be used.^14,55 For severe itching, a sedating antihistamine, such as hydroxyzine (10-25 mg every 4 to 6 hours prn), might help relieve symptoms; H₁- and H₂-receptor antagonists can be used concomitantly.^54,55

Significant local symptoms. Large local reactions are treated with a midpotency topical corticosteroid (eg, triamcinolone acetonide cream 0.1% bid) plus an oral antihistamine to relieve pruritus and reduce allergic inflammation. For a more severe reaction, an oral corticosteroid (prednisone 1 mg/kg; maximum dosage, 50 mg/d) can be given for 5 to 7 days.^54-56

Management of a necrotic ulcer secondary to a brown recluse spider bite is symptomatic and supportive. The size of these wounds can increase for as long as 10 days after the bite; resolution can require months of wound care, possibly with debridement. Rarely, skin grafting is required.^27,28,31

VIT. Some studies show that VIT can improve quality of life in patients with prolonged, frequent, and worsening reactions to insect bites or stings and repeated, unavoidable exposures.^55,56 VIT is recommended for patients with systemic hypersensitivity and a positive venom skin test result. It is approximately 95% effective in preventing or reducing severe systemic reactions and reduces the risk of anaphylaxis (see next section) and death.⁵⁷ The maintenance dosage of VIT is usually 100 μg every 4 to 6 weeks; optimal duration of treatment is 3 to 5 years.⁵⁸

Continue to: After VIT is complete...

• a history of severe, life-threatening allergic reactions to bites and stings
• honey bee sting allergy
• mast-cell disease
• a history of anaphylaxis while receiving VIT.

Absolute contraindications to VIT include a history of serious immune disease, chronic infection, or cancer.^58,59

Managing anaphylaxis

This severe allergic reaction can lead to death if untreated. First-line therapy is intramuscular epinephrine, 0.01 mg/kg (maximum single dose, 0.5 mg) given every 5 to 15 minutes.^14,60 Epinephrine auto-injectors deliver a fixed dose and are labeled according to weight. Administration of O₂ and intravenous fluids is recommended for hemodynamically unstable patients.^60,61 Antihistamines and corticosteroids can be used as secondary treatment but should not replace epinephrine.⁵⁶

After preliminary improvement, patients might decompensate when the epinephrine dose wears off. Furthermore, a biphasic reaction, variously reported in < 5% to as many as 20% of patients,^61,62 occurs hours after the initial anaphylactic reaction. Patients should be monitored, therefore, for at least 6 to 8 hours after an anaphylactic reaction, preferably in a facility equipped to treat anaphylaxis.^17,56
 

The scent of botanic oils, including lavender and peppermint, can help prevent infestation by fleas.

Before discharge, patients who have had an anaphylactic reaction should be given a prescription for epinephrine and training in the use of an epinephrine auto-injector. Allergen avoidance, along with an emergency plan in the event of a bite or sting, is recommended. Follow-up evaluation with an allergist or immunologist is essential for proper diagnosis and to determine whether the patient is a candidate for VIT.^14,17

CORRESPONDENCE
Ecler Ercole Jaqua, MD, DipABLM, FAAFP, 1200 California Street, Suite 240, Redlands, CA 92374; ejaqua@llu.edu.