Before implementing clinical and public health interventions, one must actively hypothesise and describe potential side effects and only then decide whether they are worth being quantified on not. Most scientific articles and guidelines in the context of the covid-19 pandemic highlight two potential side effects of wearing surgical face masks in the public, but we believe that there are other ones that are worth considering before any global public health policy is implemented involving billions of people…”

Antonio I Lazzarino, Medical Doctor and Epidemiologist, Steptoe A, Hamer M, Michie S, University College London UCL Institute of Epidemiology and Health Care. Rapid Response: Covid-19: important potential side effects of wearing face masks that we should bear in mind. BMJ Rapid Response to Face Masks for the Public during the COVID-19 Crisis20 April 2020.  https://www.bmj.com/content/369/bmj.m1435/rr-40