Studies of transmission of SARS-CoV2 suggest a spectrum between droplet and aerosol spread, even in asymptomatic patients and absence of aerosol generating procedures (5). Thus the type of masks worn by medical practitioners may mitigate risk to different degrees. Our equation is modifiable, according to local prevalence, transmission efficiency, number of patients seen per year by the provider, and quality of mask mitigation. Eyewear may further mitigate this risk (4). The figure shows that while the risk of acquiring Covid-19 in a year of practice is low, it is not negligible. However it can be minimized. These considerations may be helpful in deciding local risk to the practitioner according to practice volume and in choosing the level of PPE that would result in minimizing that risk.
Julian Allen, MD
Tryce Scully, MS
The Children’s Hospital of Philadelphia
References
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