evidence: When the COVID-19 pandemic took off in 2020, so too did questions over the effectiveness of wearing a face mask to prevent the spread of the virus. Now, four years later, what does the science say? [...] "Masks, even cloth masks, do something," she said. [...] Early in the pandemic, some guidance from health professionals suggested that wearing a mask might actually lead to infection: A person might encounter a contaminated mask and then touch their eyes, nose, or mouth. But research in the ensuing years has shown that fear to be misplaced.