I’m not an epidemiologist, but I do sometimes teach logic. So check out this bit of public health polemic from CIDRAP: There is some evidence that surgical masks can be effective at reducing overall particle emission from patients who have multidrug-resistant tuberculosis,36 cystic fibrosis,34 and influenza.33 The latter found surgical masks decreased emission of large particles (larger than 5 µm) by 25-fold and small particles by threefold from flu-infected patients.33 Sung37 found a 43% reduction in respiratory viral infections in stem-cell patients when everyone, including... Read more