Surgical and cotton masks were ineffective at preventing the dissemination of SARS-CoV-2, the virus that causes COVID-19, according to a research letter published in Annals of Internal Medicine.
Researchers recruited four patients from South Korea with COVID-19. Two of the patients had upper respiratory infections: one had pneumonia and the other had pneumonia with acute respiratory distress syndrome. The age of the patients ranged from 35 to 82 years. Two of the patients were women.
Patients were asked to cough five times into a petri dish without wearing a mask, while wearing a disposable