A pediatric pulmonologist's cumulative risk of acquiring Covid-19 in outpatient practice

Pediatric pulmonologists, and, indeed, general pediatricians, are exposed to the causative virus of Covid-19 , SARS-CoV2, in their daily outpatient practices from both symptomatic and asymptomatic patients. This risk naturally increases with multiple exposures over time. We have developed a simple equation to calculate the probability of a practitioner remaining Covid free over a specified time interval, given the local population prevalence of virus, the transmissibility of the organism or “attack rate,” the mitigating effects of personal protective equipment (PPE), and the number of patients seen over the time interval. The equation can be used to construct a Kaplan Meier -like plot for remaining Covid free. Since studies of transmission of SARS-CoV2 suggest a spectrum between droplet and aerosol spread, even in asymptomatic patients and absence of aerosol generating procedures, the type of masks protection worn by medical practitioners may mitigate risk to different degrees. Eye protection may mitigate the risk further. 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.