My (highly speculative!) hypothesis is that the emergence of these variant viruses arises in cases of chronic infection during which the immune system places great pressure on the virus to escape immunity and the virus does so by getting really good at getting into cells. 11⁄19
That’s plausible, but doesn’t explain why the chronic infections hadn’t done this earlier, and the English strain doesn’t escape immunity in this way (and we don’t know about the others) so I notice it doesn’t feel like it explains things.
Here is a National Geographic article on how new therapies may have allowed chronic patients to be kept alive for longer and with higher viral loads, and may have influenced viral evolution. In particular, the article cites a preprint on Medrxiv which finds that convalescent plasma therapy leads to rapid changes in spike proteins and to the evolution of antibody resistance.
Here is a National Geographic article on how new therapies may have allowed chronic patients to be kept alive for longer and with higher viral loads, and may have influenced viral evolution. In particular, the article cites a preprint on Medrxiv which finds that convalescent plasma therapy leads to rapid changes in spike proteins and to the evolution of antibody resistance.