[bagels]

Are there any variants that can spread from birds to humans but not from humans to humans? Definitely not an expert in this at all, but it seems like the virus wouldn't care where it was before it got in to someone's mucous membranes. I can certainly imagine some modes of transfer will be less likely because maybe this variant causes chickens to sneeze, but not people, greatly reducing transmissivity, but seems unlikely to me to be impossible.

[ls612]

Most bird flu in the past only spreads from birds to humans, or is like MERS in that it can technically spread human to human but with an R0 far less than 1.

[Izkata]

> mucous membranes

Depends on which membranes. I think I remember reading that the reason these can transfer bird-to-human but not human-to-human is that they can only infect us if it gets so deep into the lungs we can't actually expel it from breathing or coughing.

[onlyrealcuzzo]

My understanding is that most bird flu variants that spreads from birds to humans does not also spread from humans to humans.