There's a study indicating that a cheap nasal spray that is already on the market (for allergies) can reduce Covid 19 infection risk by ~2/3rd, and also reduce other respiratorial infections. I'm somewhat torn between "too good to be true" and "any reason I shouldn't immediately buy and use this?"
Anyone read any insightful (and particularly: skeptical, caveats) takes on it?
https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2838335