I’m not that sure. A lot of experts agree that there’s not much quality data to reach that conclusion.
Most “definitive proof” comes from mechanical studies (they measure how far your saliva is reaching with and with out mask), but that’s not the only important factor.
Masks are not designed for full day use, and by wearing them everyone is constantly touching their face, mouth and nose. This sounds to me like a way worse infection vector. Viruses like covid can survive for a long time on surfaces.
It’s hard to separate the effects of masks from that of hand sanitizer, vaccinations, or other measures taken.
Nurses working in the ICU during the beginning of the pandemic would use the same mask for an entire week without losing efficacy. If the masks didn't work, we would have seen a huge number of them infected in the NYC hospitals but that didn't happen. Most viruses don't survive very long on surfaces.
ICU nurses wear N95 masks that are fitted and tested (a bad tasting/smelling aerosol is used). It is completely sealed around the face. This is how my SIL did COVID ICU for 1.5 years every week without contracting it. Not the same as the one size fits all n95 people loosely place on their faces.
I’m not that sure. A lot of experts agree that there’s not much quality data to reach that conclusion.
Most “definitive proof” comes from mechanical studies (they measure how far your saliva is reaching with and with out mask), but that’s not the only important factor.
Masks are not designed for full day use, and by wearing them everyone is constantly touching their face, mouth and nose. This sounds to me like a way worse infection vector. Viruses like covid can survive for a long time on surfaces.
It’s hard to separate the effects of masks from that of hand sanitizer, vaccinations, or other measures taken.