It has to be less deadly, more virulent, and confer immunity against other strains.My theory is those countries volunteering to be a petri dish might end up doing the world a favour. Some delta variant hopefully mutate to something less deadly.
I think he did it because the Zorro mask covers the eyes but not the nostrils or mouth.That's kinda funny.
I've been thinking of a Mandalorian costume or the snake armor costume from Assassin's Creed Odyssey as you can wear a mask under them.
It has to be less deadly, more virulent, and confer immunity against other strains.
The reason why Delta is displacing other strains is not because they mutated into Delta. It is because Delta is out-competing them. The other strains are being beat back by NPI and vaccination and the people they try to infect already being infected by Delta.
Non-Delta level strains are completely crippled by the vaccine; almost nobody develops symptoms and they spread it really poorly. Delta is only slowed down by the vaccines.
On one hand, there is the droplet and fomite side. These are the people who say "stay 2 m apart", "use plexiglass barriers", "wash hands and surfaces frequently".
On the other, aerosol. These are the people who say "interact outdoors", "be well ventilated", "wear masks, n95 or medical grade ideally", "install air filters".
The belief that respiratory illness spreads via ballistic droplets and fomites, and only rarely via airborn transmission, looks like a 50+ year old error caused by the fact that TB requires 5 nm particles to reach the bottom of your lungs and infect people. Particles larger than 5 nm get caught in the upper respiratory tract.
Covid 19 5 - 100 nm particles (of saliva) can stay airborn for quite a long time
Okay, I'm sorry, but you seem to making a bit of a hash of terms.
"Droplet" is anything over about 5 micrometers. "Aerosol" is just a small droplet (under about 50 micrometers). The effective difference between "droplet" transmission and "aerosol" in this context is the length of time the drops stay in the air. Any droplet over 100 micrometers falls out of the air in seconds. From there, the smaller the drop, the longer the hang time.
The vast majority of SARS-COV-2 transmission is by droplet. The pattern of spread we see in Covid-19 in the population is not consistent with aerosol droplets that stay in the air for more than about a half an hour. And, the vast majority of cases are still from folks you were in close immediate contact with - you are both present and within about 6 feet of each other.