Someone made an interesting point that we got rid of cholera by drinking cleaner water and that we'll get rid of Covid by breathing cleaner air.
You won't often catch covid from stray particles but from the person breathing next to you, which these filters can't help. This study was in a hospital where everyone is wearing serious PPE, so its a super edge case to get rid of covid in the air because the main use case of catching covid has been handle by plain old PPE. This doesn't have sweeping applicability. It won't stop covid among the general population. It…
- Extended time indoors, with high viral loads. It spreads ridiculously well with no protection (even among the vaccinated).
- Isolated superspreader events, where one person infects many, even with distant contact.
Filters would seem to target the latter more than the former.