Mass masking in the COVID-19 epidemic: people need guidance

As the spread of coronavirus disease 2019 (COVID-19) outside China is accelerating, we urge policy makers to reconsider the role of masking. The non-specific symptoms at early stages of COVID-19 and absence of clear transmission links have defied conventional containment strategy by case isolation and contact quarantine.1Guan WJ Ni ZY Hu Y et al.Clinical characteristics of the 2019 novel coronavirus infection in China.NEJM. 2020; (published...