Because it is impossible to say what new insanities await, I hesitate to declare any particular post the last on a given subject, but I’d be very happy if this is the last time I ever type up anything of any length about masks. No measure has been so thoroughly debunked and destroyed by the events of the pandemic than this one, and if we lived in a rational world, the market for these largely useless medical devices would shrink to a few special use cases. Even surgical masks in hospitals appear to be basically worthless, if not slightly harmful, when it comes to preventing infection in patients during surgery.
The well-regarded Cochrane Library have updated their review of the study evidence for Physical interventions to interrupt or reduce the spread of respiratory viruses. They look at high-quality studies on the efficacy of both masking and handwashing against Covid and influenza infection. Handwashing appears to slightly reduce your likelihood of acquiring flu and Covid, but masks – to the surprise of absolutely nobody, except the profoundly stupid, the deeply disturbed, or the ideologically committed – do zero: