4 ms·

Just a no sources comment: you can get confection of the flu and covid or any variant with any other variant at the same time. It's just over time one variant o

Just a no sources comment: you can get confection of the flu and covid or any variant with any other variant at the same time. It's just over time one variant out competes the others because it's more fit.

omnicognate 5y ago
Dumb question that's been vaguely nagging at me: If a host can have both at the same time, in what sense are they competing? There are plenty of cells to infect in a particular host aren't there?
- regularfry 5y ago
  They're competing to infect the next hosts in the chain. With two present, the one that can get itself passed on more often wins overall.
  - omnicognate 5y ago
    Ah, so you can contract both viruses but are only likely to pass one on? Do you know why that is?
    - regularfry 5y ago
      They have different transmission probabilities. Omicron has far more presence in the upper respiratory tract. It's just a numbers game, they're not competing in any active sense.
      - omnicognate 5y ago
        In that case I don't understand the "omicron will outcompete other variants" thing I keep reading about. If they don't interact wouldn't the progress of one variant be unaffected by the presence of another?
        Imnimo 5y ago
        I think you're correct - if Omicron and Delta provided no cross-immunity, there would be no competition, and they would just continue on their own trajectories as if the other didn't exist. But, I think that's not actually the case. Omicron infection does provide some immunity against Delta. See this preliminary report from South Africa, for example: https://www.ahri.org/omicron-infection-enhances-neutralising-immunity-against-delta/ https://www.ahri.org/omicron-infection-enhances-neutralising... I'm not an expert (so take this next part with a very large grain of salt), but I would guess that someone with an active Omicron infection (and so swarming with antibodies) would get the biggest immunity boost against Delta. So if Omicron is everywhere, Delta runs out of infectable hosts. In principle, it could even go extinct - if that were to happen, it wouldn't matter so much if Omicron-induced immunity wanes, there would be no Delta left once the shields are down.

omnicognate 5y ago

Dumb question that's been vaguely nagging at me: If a host can have both at the same time, in what sense are they competing? There are plenty of cells to infect in a particular host aren't there?

regularfry 5y ago
They're competing to infect the next hosts in the chain. With two present, the one that can get itself passed on more often wins overall.
- omnicognate 5y ago
  Ah, so you can contract both viruses but are only likely to pass one on? Do you know why that is?
  - regularfry 5y ago
    They have different transmission probabilities. Omicron has far more presence in the upper respiratory tract. It's just a numbers game, they're not competing in any active sense.
    - omnicognate 5y ago
      In that case I don't understand the "omicron will outcompete other variants" thing I keep reading about. If they don't interact wouldn't the progress of one variant be unaffected by the presence of another?
      - Imnimo 5y ago
        I think you're correct - if Omicron and Delta provided no cross-immunity, there would be no competition, and they would just continue on their own trajectories as if the other didn't exist. But, I think that's not actually the case. Omicron infection does provide some immunity against Delta. See this preliminary report from South Africa, for example: https://www.ahri.org/omicron-infection-enhances-neutralising-immunity-against-delta/ https://www.ahri.org/omicron-infection-enhances-neutralising... I'm not an expert (so take this next part with a very large grain of salt), but I would guess that someone with an active Omicron infection (and so swarming with antibodies) would get the biggest immunity boost against Delta. So if Omicron is everywhere, Delta runs out of infectable hosts. In principle, it could even go extinct - if that were to happen, it wouldn't matter so much if Omicron-induced immunity wanes, there would be no Delta left once the shields are down.