"A cluster randomised trial of cloth masks compared with medical masks in healthcare workers". Conclusion: "The rates of all infection outcomes were highest in the cloth masks."
https://bmjopen.bmj.com/content/5/4/e006577
"A cluster randomised trial of cloth masks compared with medical masks in healthcare workers". Conclusion: "The rates of all infection outcomes were highest in the cloth masks."
chadtrader
https://bmjopen.bmj.com/content/5/4/e006577