Thread by @DrEricDing

Worrisome discovery—Among placebo group for Novavax’s vaccine in South Africa🇿🇦: people with prior #COVID19 infections appeared just as likely to get sick as people without prior infections—means past infection wasn’t fully protective for #B1351 variant.🧵
washingtonpost.com/health/2021/02…

2) The #B1351 has swiftly become dominant in South Africa, but has been found worldwide. The variant has been detected only a handful of times in the United States, including a case reported Friday in Virginia—3rd US state to identify the presence of the #B1351 variant.

3) The preliminary finding from the 🇿🇦 vaccine trial (placebo group), based on a data set with limitations, stirred debate and concern among researchers. Also notice how the #B1351 variant has become near “dominant” in South Africa? Not a coincidence.

4) Dr Fauci: “The data really are quite suggestive: The level of immunity that you get from natural infection — either the degree of immunity, the intensity of the immunity or the breadth of immunity — is obviously not enough to protect against infection with the mutant”

5) Fauci noted that a **vaccine is better than natural infection in protecting people**, calling it “a big, strong plug to get vaccinated”...

And reality check for people who may have assumed immunity because already been infected. (natural herd immunity advocates listen up!)

6) Digging into the data (placebo group only)—notice how the incidence of total #COVID19 was equal at 3.9% between people with prior infections (seropositive) vs not?

➡️Notice incidence of moderate/severe was ~same too! Prior infection had no protection for even severe COVID!

7) The good thing is that the Novavax vaccine was roughly equally ~50% effective (in South Africa 🇿🇦, higher elsewhere) against the virus regardless of past infection (denoted as serostatus positive or negative in the figure). All the more reason to vaccinate.

8) Also notice how there was slightly higher efficacy of 60% in regular HIV negative patients in South Africa.

9) In the U.K. study of the Novavax vaccine (when #B117 was still ~half of all cases... the good old days), the Novavax vaccine had a good 89.3% efficacy. Much much higher than the ~50% in South Africa 🇿🇦 where #B1351 was dominant. novavax.com/sites/default/…

10) The Reinfection data shows the risks of a strategy to reach herd immunity pushed by Scott Atlas, adviser to President Donald Trump, who is said to have endorsed allowing the virus to spread mostly unfettered, while protecting nursing homes and other vulnerable populations.

11) The study backs up recent laboratory data from South African researchers analyzing blood plasma from recovered patients. 48% was completely unable to block the #B1351 pseudovirus in lab study. biorxiv.org/content/10.110…

12) Bottomline: #B1351 is a beast that increases the likelihood of reinfection for those who thought they had protection from prior #COVID19. Good news is vaccines do work & clearly work better than natural infection immunity (little to none against B1351). Vaccinate please.

13) ... we at @FAScientists warned previously about the likelihood that #B1351 (which has the bad E484K mutation) might be concerning for reinfection. Some dismissed this as “fearmongering” that it almost never happens. Yet we see this a lot now, which has gotten Fauci concerned.

https://twitter.com/alinouriphd/status/1347016588579508224

14) Fauci: “We have to be concerned about the mutants” 👀

Fauci right on the concern for the #B117, #B1351, #P1.

We gotta end pandemic fast with vaccines and #ZeroCovid approach, or else we will be back to square one again. Another wave is brewing.