Thread by @DavidLat

Is anyone aware of research on the susceptibility to the Delta variant of people who had a natural infection of #COVID19 (seropositive) and then got fully vaccinated with an mRNA vaccine on top of that?

Asking for a friend.

Cc’ing @florian_krammer @DrTomFrieden @VirusesImmunity @apoorva_nyc who have been insightful in the past.

3/ Just went to @nyulangone to give blood for a research study I joined back in March 2020, when I was hospitalized there. I go there every few months to donate.

4/ I asked if they have had any subjects who got #COVID19, got vaccinated, and got reinfected with #COVID19; they have not. Their research shows robust immune response (but note that this isn’t about Delta specifically).

bit.ly/3iwnQ4F

5/ Thanks for all the great responses, everyone! They fall into several categories.

First, comments that based on earlier research, prior infection plus vaccination seems to confer robust immunity that should cover Delta. E.g.,

https://twitter.com/apoorva_nyc/status/1417905086689316870

6/ Second, comments citing studies showing that in general, the mRNA vaccines seem to be effective against the current known variants, including Delta.

7/ Third, a study showing that prior infection + vaccination seems to work well against Delta (thanks, @MaxKennerly):

https://twitter.com/MaxKennerly/status/1417891472947531777

8/ Fourth, some anecdotal accounts of folks who had Covid, got vaccinated, got Delta, and experienced mild illness.

9/ Fifth, a very small number of anecdotal accounts of folks who had Covid, got vaccinated, got Delta, and experienced serious illness.

10/ Bottom line: those of us who had #COVID19 and then got #vaccinated with two shots of an mRNA vaccine are unlikely to get reinfected, even with Delta, or experience serious illness in the event of reinfection with Delta.

11/ All that said, it's never a bad idea to take reasonable precautions, especially if they are not a big deal or burden.

Thanks again to everyone for the helpful information and responses!

(Feel free to poke around in the thread for details and links.)