Claim: New documents reveal that Pfizer's Covid-19 vaccine has just 12% efficacy.
Fact-check: Post claiming the Pfizer vaccine has only a 12% efficacy rate is inaccurate - Full Fact
Verdict: this appears to be based on a misinterpretation of a document showing results from a clinical trial first published in 2020. the clinical trial showed the vaccine's efficacy rate was 95% from seven days after the second dose, although the latest data relating to the omicron variant does show lower efficacy which reduces significantly over time.
Organisation: Full Fact
Author: Hannah Smith
Date published: 2022-05-17T00:00:00