Nature: Vaccine effectiveness against Delta wanes

According to this massive study in the scientific journal Nature, hence the need for booster shots.

"The vaccine made by Pfizer in New York City and BioNTech in Mainz, Germany, was 92% effective at keeping people from developing a high viral load — a high concentration of the virus in their test samples — 14 days after the second dose. But the vaccine’s effectiveness fell to 90%, 85% and 78% after 30, 60 and 90 days, respectively. The vaccine developed by Oxford and the pharmaceutical company AstraZeneca in Cambridge, UK, was 69% effective against a high viral load 14 days after the second dose, falling to 61% by 90 days."

So what about the drop in effectiveness after 90 days? What about after 4, 5, 6 months? Recall back in July that the Israel Ministry of Health claimed the Pfizer vax was only 39% effective. The CDC is recommending that you get the booster 8 months after your full vaccination. If Israel is any guide we'll likely be near their numbers by then.