The bad news: On Thursday, Science published the largest study to date looking at the effectiveness of COVID-19 vaccines over an extended period. The results of that study are not great.  Looking at a pool of over 780,000 veterans—just under 300,000 of them unvaccinated—the initial effectiveness of all the vaccines was just about as good as advertised. At the peak of protection—a week after the second shot (or a few weeks after the first shot, in the case of Johnson & Johnson)—the average level of protection against infection was 87.9%. However, eight months later, protection against infection had dropped to 48.1%. For Johnson & Johnson, that level of protection against infection was down to just 13.1%. The news on protecting against deaths was much better. For veterans under 65, Pfizer-BioNTech provided an 84.3% improvement in the rate of death at the end of the study, Moderna was at 81.5%, and Johnson & Johnson was at 73.0%. For those over 65, the protection was 70.1%, 75.5%, and 52.2%, respectively.  It’s not that these numbers weren’t expected, but seeing them in black and white, in such a large study, is still somewhat sobering. There is a reason that the Centers for Disease Control and Prevention (CDC) recommends boosters for all Johnson & Johnson vaccine recipients. One other thing: It’s easy to read this as the vaccines having a definitive expiration date, but the actual study isn’t really able to differentiate between the effect of vaccines declining over time from the growing dominance of the delta variant. Barring the entry of a new variant that is more vaccine-evasive, vaccines may remain effective over a longer period. That’s still unclear. Let’s get to the good news. Read more