Thread by @ariehkovler

Israel will begin giving older people a THIRD DOSE of the Pfizer coronavirus vaccine, following the recommendation of a government advisory panel. PM Naftali Bennett will make the final decision today.

Israel is currently seeing a sharp spike in infections of the Delta variant, and preliminary figures seemed like older people's vaccine-induced protection *might* be waning.

Pfizer and the Health Ministry have been mooting a third dose for months, backed by former PM Netanyahu who's been an advocate of a booster dose since before the Delta wave arrived.

Israel, of course, was one of the first countries to vaccinate its elderly population with 2 doses of Pfizer (on a 3-week dosing schedule), so if there WAS waning immunity, it's possible places with later vaccination or a longer dosing schedule won't show it.

On the other hand, there's some evidence that immunity might not be waning all that much, and that the initial analysis was flawed. Lots of noise in the data.

https://twitter.com/dvir_a/status/1420059129008336905

We do know that a longer interval between the first two doses seems to produce better antibody levels and immune memory than a 3-week interval. So there's good reason to think a third dose will help here too.

bbc.com/news/health-57…

The booster dose will the the original Pfizer-BioNTech formulation. A Delta-specific version of the vaccine is under development but it isn't out yet.

Also still to be decided: the cutoff age for booster doses. 70? 65? 60?

Worth noting that this plan is controversial in Israel. Some worry that pushing a third dose could undermine public confidence in the vaccine.

https://twitter.com/ariehkovler/status/1420633152582737920

Others say that the priority should be vaccinating 12-19-year-olds, an age group where uptake has been low, or to trying to convince the unvaccinated holdouts among the over-50s (vaccination coverage chart below)

Final: Israel will administer booster doses of the Pfizer vaccine to all residents over the age of 60. Most of this age group was vaccinated at the beginning of the year.