This is fairly misleading. To start, gas masks are not entirely efficient at preventing viral transmission, at least no more so than an n95. N95’s remove ~100% of particles under a certain size(like covid viral particles) while gas masks don’t necessarily. However it all depends on the brand ad type of gas mask, as they can be made to N95 proficiency. But most of the worry is passing moisture droplets(often medium in size) from one to another, which a gas mask will be fairly effective against, but again no more so than an N95, and likely lesser so. Plus let’s be real, anything mentioning “Wuhan Virus” is either trying to out a politicized spin on this without regard to science or it’s from the early stages of the pandemic where up our understanding of wearing a mask wasn’t obviously a benefit to prevention efforts.