Thread by @DrEricDing

Good summary on the efficacy of the 6 reported Phase 3 vaccines by the ever wonderful @MonicaGandhi9. Though caveats on #B1351 variant:

📍Moderna & Pfizer efficacy unknown for 🇿🇦; lab shows lower neutralization.

📍Sputnik not tested 🇿🇦

📍New AZ data shows low 22% #COVID19

https://twitter.com/monicagandhi9/status/1356818441064206337

2) to be clear, the 22% efficacy against mild disease for the #B1351 variant was not significant in the new Oxford-AstraZeneca trial report. For severe diseases, it was okay for neutralization but no efficacy data yet. SA has switched vaccines they will be using meantime.

https://twitter.com/drericding/status/1358511988851245058

3) The South Africa 🇿🇦 variant has very evasive properties of seemingly evading prior immunity from natural infection. Prior infection was not protective against #B1351- not even for severe disease. But fortunately, several vaccines do work them n

https://twitter.com/DrEricDing/status/1358065355785134083

4) The South Africa 🇿🇦 #B1351 fighting efficacy of AstraZeneca vaccine was indeed poor, 22% and not significant for mild and moderate infection. But... that wasn’t true before B1351 emerged.

5) early on in the Oxford-AstraZeneca trial, before B1351 became dominant, the vaccine had an efficacy of 75% risk reduction!!! But all that disappeared once B1351 variant showed up!