Pfizer and BioNTech say their COVID-19 vaccine is about 91 per cent effective at preventing the disease, citing updated trial data that included participants inoculated for up to six months.
- The new overall efficacy rate of 91.3 per cent is lower than the 95 per cent originally reported in November
- A number of variants have become more prevalent around the world since then
- The drugmakers plan to submit for full US regulatory approval
The shot was also 100 per cent effective in preventing…