Personal protective equipment (PPE) is an important component in limiting transmission of SARS-CoV-2. The World Health Organization and Centers for Disease Control and Prevention issued guidelines for appropriate PPE use, but recommendations for head and shoe coverings are lacking. In this article, we analyze the literature on pathogen transmission via hair and shoes and make evidence-based recommendations for PPE selection during the COVID-19 pandemic.
Pathogens on Shoes and Hair
Hair and shoes may act as vehicles for pathogen transmission. In a study that simulated contamination of uncovered skin in health care workers after intubating manikins in respiratory distress, 8 (100%) had fluorescent markers on the hair, 6 (75%) on the neck, and 4 (50%) on the shoes.1 In another study of postsurgical operating room (OR) surfaces (517 cultures), uncovered shoe tops and reusable hair coverings had 10-times more bacterial colony–forming units compared to other surfaces. On average, disposable shoe covers/head coverings had less than one-third bacterial colony–forming units compared with uncovered shoes/reusable hair coverings.2
Hair characteristics and coverings may affect pathogen transmission. Exposed hair may collect bacteria, as Staphylococcus aureus and Staphylococcus epidermidis attach to both scalp and facial hair. In one case, β-hemolytic streptococci cultured from the scalp of a perioperative nurse was linked to postsurgical infections in 20 patients.3 Hair coverings include bouffant caps and skullcaps. The bouffant cap is similar to a shower cap; it is relatively loose and secured around the head with elastic. The skullcap, or scrub cap, is tighter but leaves the neck nape and sideburns exposed. In a study comparing disposable bouffant caps, disposable skullcaps, and home-laundered cloth skullcaps worn by 2 teams of 5 surgeons, the disposable bouffant caps had the highest permeability, penetration, and microbial shed of airborne particles.4
Physicians’ shoes may act as fomites for transmission of pathogens to patients. In a study of 41 physicians and nurses in an acute care hospital, shoe soles were positive for at least one pathogen in 12 (29.3%) participants; methicillin-resistant Staphylococcus aureus was most common. Additionally, 98% (49/50) of shoes worn outdoors showed positive bacterial cultures compared to 56% (28/50) of shoes reserved for the OR only.5 In a study examining ventilation effects on airborne pathogens in the OR, 15% of OR airborne bacteria originated from OR floors, and higher bacterial counts correlated with a higher number of steps in the OR.2 In another study designed to evaluate SARS-CoV-2 distribution on hospital floors, 70% (7/10) of quantitative polymerase chain reaction assays performed on floor samples from intensive care units were positive. In addition, 100% (3/3) of swabs taken from hospital pharmacy floors with no COVID-19 patients were positive for SARS-CoV-2, meaning contaminated shoes likely served as vectors.6 Middle East respiratory syndrome, SARS-CoV-2, and influenza viruses may survive on porous and nonporous materials for hours to days.7Enterococcus, Candida, and Aspergillus may survive on textiles for up to 90 days.3
Recommendations for Hair and Shoe Coverings
We recommend that physicians utilize disposable skullcaps to cover the hair and consider a hooded gown or coverall for neck/ear coverage. We also recommend that physicians designate shoes that remain in the workplace and can be easily washed or disinfected at least weekly; physicians may choose to wash or disinfect shoes more often if they frequently are performing procedures that generate aerosols. Additionally, physicians should always wear shoe coverings when caring for patients (Table 1).
Our hair and shoe covering recommendations may serve to protect dermatologists when caring for patients. These protocols may be particularly important for dermatologists performing high-risk procedures, including facial surgery, intraoral/intranasal procedures, and treatment with ablative lasers and facial injectables, especially when the patient is unmasked. These recommendations may limit viral transmission to dermatologists and also protect individuals living in their households. Additional established guidelines by the American Academy of Dermatology, American Society for Dermatologic Surgery, and World Health Organization are listed in Table 2.8-10
Current PPE recommendations that do not include hair and shoe coverings may be inadequate for limiting SARS-CoV-2 exposure between and among physicians and patients. Adherence to head covering and shoe recommendations may aid in reducing unwanted SARS-CoV-2 transmission in the health care setting, even as the pandemic continues.