We have to talk about this Cochrane review of masking and handwashing that found “little to no evidence” masks (surgical & N95) reduce viral infections at the population level and some evidence that handwashing may help. Let’s dive in to understand why 1/ https://t.co/TWe7wwV38m pic.twitter.com/GjcGe4tYHy

— Jennifer Nuzzo, DrPH (@JenniferNuzzo) February 4, 2023