Thread by @celinegounder

1/ We can't underestimate SARS-CoV-2.
We've been wrong time and again. science.sciencemag.org/content/371/65…
- Viruses evolve through mutation PLUS natural selection
- When the virus replicates, it mutates.
- The more people the virus infects, the more it replicates, the more it mutates.

2/ Natural selection favors traits that allow the virus to
- replicate better
- transmit better
- and evade our immune systems better.

3/ So it makes sense that the mutant COVID variants are more infectious (e.g. B.1.1.7, B.1.526), more virulent (B.1.1.7), or evade immune responses to natural infection (e.g. B.1.351, P.1).

https://twitter.com/EricTopol/status/1373393232294408193?s=20

4/ As SARS-CoV-2 continues to spread, it will continue to mutate. What's concerning is that the S protein can mutate fairly significantly without significant loss of viral fitness... and that means the virus can mutate a lot.

5/ It is essential that we slow the spread of SARS-CoV-2 to prevent it from evolving further. We cannot allow it to evolve to where it could evade vaccine-induced immunity.

6/ It's like parking a car.
You don't take your foot off the brake (masking, ventilation, avoiding crowds)
until you shift your car into park (get enough people vaccinated).

7/ Right now, we're taking our foot off the brake and slamming on the gas (not masking, gathering in crowds, reopening indoor businesses, traveling) before the car's in park.

8/ If we slow SARS-CoV-2 transmission, we can prevent the emergence of more mutant variants and the selection of immune escape variants. But we've each got to do our part: wear a mask, avoid crowds, and get vaccinated when it's your turn.