specifically. is that what you're expecting the virus to do in other countries like the u.s., once omicron takes hold. >> yeah, i think for me, the critical issue was whether its transmissibility advantage could exceed delta. because -- and that's not clear that's the case right now. the evidence is appointing in that direction, but it's not definitive. but if it can spread faster than delta, transmissibility is going to be the key factor that will determine whether it will displace delta. and if it's going to displace delta, that means it's going to spread throughout the world, because delta is now the globally dominant variant. and if that happens, and given the rate at which it spreads, we're looking at this occurring within next few weeks to months. >> yeah. and that's what we'll be looking for. professor, as always, thank you so much for letting us know what you're seeing there on the ground.