Thread by @DrEricDing

REINFECTION & VACCINE SENSITIVITY—the concern is now growing very very real. This piece highlights the big S Africa 🇿🇦 CDC report I shared earlier, where antibodies from previously infected don’t recognize the #B1351 variant in 48% of patients. 🧵 #COVID19
nytimes.com/2021/01/20/hea…

2) “The results “strongly, strongly suggest that several mutations that we see in the South Africa variant are going to have a significant effect on the sensitivity of that virus to neutralization” says a virologist from @nicd_sa, South Africa’s CDC.

3) And the #B1351 variant did not just 48% had “complete immune escape”, but 90% also showed reduced immune response. That’s a lot.

4) “Fears that the vaccines would be powerless against new variants intensified at a scientific conference held online on Saturday, when South African scientists reported that in laboratory tests, serum samples from 21 of a group of 44 Covid-19 survivors did not destroy #B1351.

5) “The samples that were successful against the variant were taken from patients who had been hospitalized, who had higher blood levels of so-called neutralizing antibodies — the subset of antibodies needed to disarm the virus & prevent infection — than those only mildly ill.”

6) What about blood from vaccinated people? One study tested blood from 14 people who had received Moderna vaccine (white) & 6 who had received Pfizer-BioNTech (red). There was a drop in neutralizations w/ both N501Y (many variants) and E484K mutations (#B1351 & #p1 variants).

7) Furthermore, “neutralization by 14 of the 17 most potent mAbs (monoclonal antibodies — eg Regeneron drug) tested was reduced or abolished by either K417N, or E484K, or N501Y mutations.” Not good.
biorxiv.org/content/10.110…

8) That said, Dr. Nussenzweig said it “is not something that we should be horribly freaked out about.” It is a “sight drop”.

The vaccine results are much better than convalescent blood of naturally infected patients— that makes sense. Because vaccine induced stronger immunity.

9) I wrote a much more detailed thread 🧵 yesterday summarizing different variants and what we know so far. Here is the exact declaration by South Africa’s CDC warning about #B1351. And then I explain the E484K mutation that it has.

Read below ⬇️

https://twitter.com/drericding/status/1351686170044989442

10) Keep in mind that vaccines are different from natural infection. The 48% immune escape highlighted above is among convalescent patients.

Vaccine offers STRONGER & more ROBUST long term immunity than natural infection—seen in P1/P2 trial of both Pfizer & Moderna vaccines.

11) The vaccine will still work for sure. It just maybe be a few minor % drop in efficacy from 95% (2 doses)... but even if 70-90%, that is still better than 0% protection w/out a vaccine!

And vaccines work 100% against severe disease, which you don’t want.