Identifying the optimal amount of personal protective equipment (PPE) is a formidable challenge when faced with a new contagion such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Unequivocally, there are dangers to health care workers (and by extension, their patients, colleagues, and communities) if not enough equipment is donned to safeguard them. And yet, there are also dangers to patients, colleagues, and the community if resources are overconsumed and result in hoarding, shortages, and inequitable distribution, all of which are occurring as the worldwide coronavirus disease 2019 (COVID-19) pandemic continues.
Research to ascertain the precise PPE required to defend specifically against SARS-CoV-2 encompasses an area of active investigation that will likely remain unresolved for some time. While awaiting more definitive conclusions, we must look to past evidence to provide a reasonable basis on which protocols and policies might be refined. What follows is a narrative review of PPE efficacy and how existing evidence might apply to protecting health care workers against COVID-19. Findings are extrapolated from investigations in 4 general domains: early investigations into SARS-CoV-2, retrospective studies about severe acute respiratory syndrome coronavirus 1, prospective studies of influenza and other common respiratory viruses, and laboratory PPE studies.
Available evidence suggests that contact and droplet precautions, in addition to eye protection and standard hygiene measures, should be adequate in the vast majority of clinical settings when caring for patients with SARS-CoV-2. Adherence to guidelines promoting appropriate levels of PPE should safeguard practitioners while mitigating against resource overuse.