The DANMASK study did NOT find that masks are not effective. It’s conclusion was that a recommendation for surgical masks in certain settings does not prevent m

The DANMASK study did NOT find that masks are not effective. It’s conclusion was that a recommendation for surgical masks in certain settings does not prevent more than 50% of infections in the wearer in a country with low case load and before any variants but that there even was a tendency towards a protective effect. So not at all meaningful in any way. What does this say about the ability of N95/FFP2 masks when all parties are wearing them to reduce the R of delta sufficiently to contain spread in communities that are seeing surges? Exactly nothing. Furthermore, designing an RCT for mask use might not really be doable in a fashion we’re used to from drug interventions. And should the vast amount of other non-RCT evidence that does exist and that shows a protective effect of masks as well as the precautionary principle not lead us all to mask up in the face of a new disease that is proven to cause serious harm, short and long term? For anybody interested in the topic, this thread by an Oxford professor and co-author of the recent Lancet letter advising against the plans of the British government might be worthwhile reading: https://twitter.com/trishgreenhalgh/status/1414294003479089154 https://twitter.com/trishgreenhalgh/status/14142940034790891... Edit: Typo.