Thread by @MonicaGandhi9

California is now the only state with 'moderate' COVID transmission - we had bad winter surge so natural immunity there and then very good vax rate with passports/mandates (puts us in category touted by CDC as safe cdc.gov/mmwr/volumes/7…)
sfchronicle.com/health/article…

Links with @DLeonhardt article from this am about blue states like CA having higher rates of COVID prior to vaccinations- our winter surge very difficult

https://twitter.com/MonicaGandhi9/status/1442574204558139393

And are you seeing the theme? High rates of natural immunity + high rates of vax (blue states) vs high but lower rates natural immunity + lower rate of vax (red states)? Theme is that immunity only way to get through pandemic if we remember history:

And people keep on tweeting me this is seasonality, vaccines don't work but that doesn't make sense immunologically (and not sure how seasonal delta is since it arose in March in India & April/May very warm months). This explains the immune response to vax
leaps.org/how-long-do-co…

Have been thinking about Israel with a low seroprevalence rate from natural infection (3.8%) & how much immunity from vaccination therefore needed (opening with less immunity had more consequence); places like CA had both; will take long time for Australia
pubmed.ncbi.nlm.nih.gov/33884542/

After terrible winter surge in CA (not helped by closing outside/over-restrictions), had at least 30% seroprevalence, didn't surge in cases again until delta, hospitalizations stayed manageable. Now low in both with high vax. Delta needs lots of immunity
sfchronicle.com/health/article…

looks like: hospitalizations stay manageable like CA if had higher rate of vax (&higher natural immunity) with delta; hospitalizations not manageable with delta if had lower vax rates (& lower rate natural immunity); Blue states higher cases before vax.
nytimes.com/2021/09/27/bri…