This claim is also taken slightly out of context so i thought I'd look into it.
There is the original tweet in which he said:
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Excited to share that updated analysis from our Phase 3 study with BioNTech also showed that our COVID-19 vaccine was 100% effective in preventing #COVID19 cases in South Africa. 100%!
https://pfizer.com/news/press-rel
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With a second tweet replying to his first
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Replying to
@AlbertBourla
800 participants enrolled in South Africa with 0 cases of #COVID19 observed in the vaccinated group. Of the cases observed the majority were confirmed to be of the B.1.351 lineage, the prevalent strain in South Africa.
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From my reading i assume they are testing a new vaccine on a different strand of covid originating in South Africa.
Surely that's a good thing being vaccines need testing before being rolled out to the masses Serafin. That was after all one of the reasons you didn't like the vaccine? Not being tested? Well it is.