As we reopen our offices we are faced with the challenge of determining the best way to do it safely – protecting ourselves, our staff, and our patients.
In this column we will focus on selected details of the recommendations from IDSA and the CDC that may be helpful in primary care offices.
Many clinicians have asked whether a physician should use a mask while seeing patients without COVID-19 in the office, and if yes, which type. The IDSA guideline states that mask usage is imperative for reducing the risk of health care workers contracting COVID-19.1 The evidence is derived from a number of sources, including a retrospective study from Wuhan (China) University that examined two groups of health care workers during the outbreak. The first group wore N95 masks and washed their hands frequently, while the second group did not wear masks and washed their hands less frequently. In the group that took greater actions to protect themselves, none of the 493 staff members contracted COVID-19, compared with 10 of 213 staff members in the other group. The decrease in infection rate occurred in the group that wore masks despite the fact that this group had 733% more exposure to COVID-19 patients.2 Further evidence came from a case-control study done in hospitals in Hong Kong during the 2003 SARS-CoV outbreak.3 This study showed that mask wearing was the most significant intervention for reducing infection, followed by gowning, and then handwashing. These findings make it clear that mask usage is a must for all health care providers who may be caring for patients who could have COVID-19.
The guideline also reviews evidence about the use of surgical masks versus N95 masks. On reviewing indirect evidence from the SARS-CoV epidemic, IDSA found that wearing any mask – surgical or N95 – led to a large reduction in the risk of developing an infection. In this systematic review of five observational studies in health care personnel, for those wearing surgical masks, the odds ratio for developing an infection was 0.13 (95% CI, 0.03-0.62), and for those wearing N95 masks, the odds ratio was 0.12 (95% CI, 0.06-0.26). There was not a significant difference between risk reductions for those who wore surgical masks and N95 masks, respectively.1,4 The IDSA guideline panel recommended “that health care personnel caring for patients with suspected or known COVID-19 use either a surgical mask or N95 respirator ... as part of appropriate PPE.” Since there is not a significant difference in outcomes between those who use surgical masks and those who use N95 respirators, and the IDSA guideline states either type of mask is considered appropriate when taking care of patients with suspected or known COVID-19, in our opinion, use of surgical masks rather than N95s is sufficient when performing low-risk activities. Such activities include seeing patients who do not have a high likelihood of COVID-19 in the office setting.
The IDSA recommendation also discusses universal masking, defined as both patients and clinicians wearing masks. The recommendation is supported by the findings of a study in which universal mask usage was used to prevent the spread of H1N 1 during the 2009 outbreak. In this study of staff members and patients exposed to H1N1 who all wore masks, only 0.48% of 836 acquired infection. In the same study, not wearing a mask by either the provider or patient increased the risk of infection.5 Also, in a prospective study of hematopoietic stem cell transplant patients, universal masking caused infection rates to drop from 10.3% to 4.4%.6
The IDSA guideline states the following: “There may be some, albeit uncertain, benefit to universal masking in the absence of resource constraints. However, the benefits of universal masking with surgical masks should be weighed against the risk of increasing the PPE burn rate and contextualized to the background COVID-19 prevalence rate for asymptomatic or minimally symptomatic HCPs [health care providers] and visitors.”1
The CDC’s guidance statement says the following: “Continued community transmission has increased the number of individuals potentially exposed to and infectious with SARS-CoV-2. Fever and symptom screening have proven to be relatively ineffective in identifying all infected individuals, including HCPs. Symptom screening also will not identify individuals who are infected but otherwise asymptomatic or pre-symptomatic; additional interventions are needed to limit the unrecognized introduction of SARS-CoV-2 into healthcare settings by these individuals. As part of aggressive source control measures, healthcare facilities should consider implementing policies requiring everyone entering the facility to wear a cloth face covering (if tolerated) while in the building, regardless of symptoms.”7
It is our opinion, based on the CDC and IDSA recommendations, that both clinicians and patients should be required to wear masks when patients are seen in the office if possible. Many offices have instituted a policy that says, if a patient refuses to wear a mask during an office visit, then the patient will not be seen.