But of the nearly 1,000 cases that were tracked back to the Provincetown parties by the end of July, there were only seven hospitalizations and no deaths. “The Provincetown numbers tell me that the vaccines are working,” Yun concluded.
All of this is to say: The data we have suggests the vaccines can turn even Delta into a flu-level nuisance, or better, in terms of the risks of hospitalization and death. There is some worry that Delta is modestly worse for children than the original strain, but the absolute risk for young kids is still quite low, and the best firewall for them is vaccinated adults. The big unknown here is the possibility for long Covid or other lingering consequences. But it’s worth noting that this is true with the flu, too. A number of chronic diseases seem to trace back to the body’s reaction to viral infections.
“Do I wish anybody long Covid? No,” Gounder told me. “Do I want to get long Covid? No. However, we run the risk in our everyday lives of getting one of these viral infections that for most people are very mild, but that can very rarely set off something like chronic fatigue syndrome or an autoimmune disease, but that’s a risk we tolerate.”
All of this made me feel a bit better. And then I talked to Bob Wachter.
Wachter is the chair of the department of medicine at the University of California at San Francisco. His main point was simply this: The numbers aren’t stable. He’s concerned that the immunity people got from past coronavirus infection is waning more quickly than we’d expected. And he thinks the same is true for vaccine-based immunity. “I think the best estimate now is the vaccines begin to lose some efficacy after six months and your immune response loses some mojo too,” he told me.
This is why Wachter supports the masking mandate in San Francisco. In his view, it’s not just the unvaccinated who benefit from masking. There may be some vaccinated people, particularly older people who got vaccines early, who will need a booster shot soon. “Two doses of the vaccines provided a healthy person a huge amount of immunologic cushion, but for a 75-year-old not so much,” Wachter told me. “Their immunity needs to wane only a modest amount before they cross the curve, before they are susceptible to a more serious infection.”
If that’s true, it suggests a future where even in highly vaccinated places, it will be a continuous fight between the immunity offered by vaccines, an always mutating virus and the speed of our booster campaigns. As Wachter dryly put it, “It’s nontrivial to go give boosters to 200 million people.” Even worse, much of the rest of the country, and even more of the rest of the world, isn’t vaccinated, which is giving the virus vast opportunities for evolution. Delta is by no means the final form the coronavirus could take.
The more optimistic outlook came from Jha. He thinks that in highly vaccinated places, we’re going to see Delta slam into a wall of vaccination, and hospitalizations and deaths won’t follow cases the way they have in the past. “Even in highly vaccinated states, unvaccinated people cluster,” he told me. “So you will see the initial rise, but once that cluster starts bumping into immunity, it won’t be able to sustain itself. We’ll find that out in the next couple of weeks in places like San Francisco and Boston.” If that happens, it’ll also be a powerful argument for vaccination in the parts of the country that have lagged and that will watch the virus tear through their communities even as more vaccinated areas are largely spared.
