Pfizer and BioNTech's Covid-19 vaccine is just 39% effective against delta in Israel, but still provides strong protection against severe illness and hospitalization.
It’s possible the UK’s longer dosing interval led to higher immunity. 3 or 4 weeks was basically a good-enough best guess by the vaccine makers and they didn’t have the “luxury” of longer studies.
When the UK first began vaccinating, 1 dose was nearly as good as 2 — at least for near-term immunity. That is no longer the case with the 🔼. The second shot really counts now. Even UK has shortened the interval.
Here is a good article: https://wellcome.org/news/what-happens-if-we-delay-second-doses-covid-19-vaccines-pfizer-oxford-moderna
It’s possible the UK’s longer dosing interval led to higher immunity. 3 or 4 weeks was basically a good-enough best guess by the vaccine makers and they didn’t have the “luxury” of longer studies.
When the UK first began vaccinating, 1 dose was nearly as good as 2 — at least for near-term immunity. That is no longer the case with the 🔼. The second shot really counts now. Even UK has shortened the interval.
Here is a good article: https://wellcome.org/news/what-happens-if-we-delay-second-doses-covid-19-vaccines-pfizer-oxford-moderna