You can more readily stop sand blowing through a chainlink fence than you can stop a virus with a mask.
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The point is not viruses but droplets, 10 to 100 times larger. But yes a properly fitted N95 will stop viruses.
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1. What happens when the droplets containing viruses vaporizes, as it will eventually do? You’d still need an airtight mask with a military grade filter, not the virtue signaling blue masks worn where leftists dwell.
2. And where has it been shown that viruses travel only in droplets?
I did a lot or research on this a year ago (man - it has been a long time!)
For the regular flu (similar size virus and transport means) lots of studies have been done. A properly fitted N-95 mask can prevent stuff 0.3 microns from coming in.
Research shows that about 50% of the time a virus is traveling on a particle that is larger than 0.3 microns, so the mask cuts the possible exposure in half.
And a decrease in dose reduces the risk to the body. Your body can fight off a small does of a virus compared to a larger dose.
The other less known thing was how long is the virus viable on a smaller particle? The moisture droplets are the big ones, and the moisture protects the envelope around the virus.
Smaller dust particles are dry, and do not protect the envelope and it can dry out and the virus is destroyed. Although those studies are less conclusive. Some think the virus is still viable, others not.
Even with moist droplets, hanging up clothing to air dry at room temperature destroys the flu virus as it dries out.
All of that said - I think it should be up to the person on whether they want to wear a mask or not. It isn’t the MASK that is controlling the people - it is the government and the “experts”.
(Yes - I was wearing a mask way back when Faucci said masks didn’t work.)
Mostly in droplets. That mainly depends on the source and if the source is aerosolizing the virus. An exhalation valve, for example, will aerosolize viruses. So if an infected person wears a mask with a valve, they will likely be a good spreader.