1/6 We need clear, transparent information on issue of delaying the 2nd Pfizer jab from 3 weeks to 12 weeks. Pfizer don't know if this is a good idea because there's no data on efficacy of 1st vaccine beyond the study interval of 21 days after which the 2nd was administered.

2/6 When UK government health advisors say that a "great majority" of initial protection comes from the first jab, what does that mean? So, we go back to source. Here is the paper in the NEJM https://www.nejm.org/doi/full/10.1056/NEJMoa2034577?query=RP

3/6 It states:
"Between the first dose and the second dose, 39 cases in the BNT162b2 group and 82 cases in the placebo group were observed, resulting in a vaccine efficacy of 52% (95% CI, 29.5 to 68.4) during this interval and indicating early protection by the vaccine.."

4/6 Can someone explain to me exactly what the numbers mean when it says "efficacy of 52% (95% CI, 29.5 to 68.4)"? The media then report 52%. This suggests if you have one jab you're 52% protected, but then when you have 2nd 3 weeks later that rises to 95% protection.

5/6 Crucially, there ARE NO DATA on what the protection is beyond 3 weeks if 2nd jab is delayed. Nor do we know if the second jab given 3 months after first still boosts protection to 95%

6/6 Please, medics, Government, media, be clear, be transparent, be honest. It's OK to say we don't know yet! It's OK to make the case for maximising the number of people getting 1st jab by delaying 2nd, even if it is at expense of reduced protection compared with 3 week gap