COVID-19 pandemic and personal protective equipment shortage: protective efficacy comparing masks and scientific methods for respirator reuse

Background and Aims: The abrupt outbreak of the novel coronavirus disease 2019 and its rapid spread over many healthcare systems throughout the world has led to a shortage in personal protective equipment (PPE), which cannot be solved by reducing their use or by increasing production. It is thus necessary to promote PPE rational use, highlighting possible differences in terms of efficacy and promoting an effective technique to reuse them. Methods: A literature search was performed on PubMed, Scopus, Cochrane database, and Google Scholar, and from the 25 top cited articles, 15 were selected for relevance and impact. Results: Most studies on previous respiratory virus epidemics to date suggest surgical masks are not inferior compared with N95 respirators in terms of protective efficacy among healthcare workers. Therefore, the use of N95 respirators should be limited to high-risk situations. Concerning respirator reuse, highly energetic, shortwave, ultraviolet germicidal irradiation (UVGI) at 254 nm was determined to decontaminate N95 respirators from viral respiratory agents, but UVGI requires careful consideration of the type of respirator and of the biologic target. Conclusions: Rational use and successful reuse of respirators can help in the shortage of PPE during a pandemic. Further studies testing UVGI and other decontamination techniques are an unmet need. The definitive answer to pandemic issues can be found in artificial intelligence and deep learning. These groundbreaking modalities could help in identifying high-risk patients and in suggesting appropriate types and use of PPE.