Home Cellular health Why the sudden surge for COVID booster shots? It’s all about...

Why the sudden surge for COVID booster shots? It’s all about the holidays


Federal officials cleared COVID-19 boosters for all U.S. adults on Friday, a move that aligns California and local health officials on the national agenda and should clear up lingering confusion over who can get vaccinated.

Boosters have been a particularly charged corner of public health policy since they were first discussed in August, and when two federal agencies – the Food and Drug Administration and the Centers for Disease Control and Prevention – established a complicated structure to recommend them.

State and local authorities – including Gov. Gavin Newsom – last week steamrolled the complex federal recommendations and quietly, then openly, advised everyone to get recalls. Health officials said federal guidelines prompted many people who needed boosters not to look for them, and said they were increasingly concerned that declining immunity – in especially among the most vulnerable populations – left communities exposed to yet another winter wave.

The advice that people are being empowered has reached a new urgency in recent days, with many public health officials begging Californians to get their shots before Thanksgiving.

“We are working to stay one step ahead of the virus,” said Dr Grant Colfax, chief of the San Francisco Department of Public Health, in a briefing this week in which he strongly advised all residents to receive reminders, and soon. “It is clear that the boosters are necessary for us to avoid a significant increase in hospitalizations and possibly also an increase in mortality. We are very aggressive with this, especially with the holiday season. “

On Friday, two months after the approval of the first recalls for limited use, the FDA and CDC both indicated that all adults should be eligible for third doses of the Pfizer and Moderna vaccines if they are at least six months after. their second injection. Everyone who received the single-dose Johnson & Johnson vaccine was already eligible at the end of last month.

The long and at times confusing conversation around reminders underscores the challenges of writing health policy in the ever-changing environment of a pandemic, as understanding of the virus and vaccine effectiveness grows in the world. over time.

Much remains unknown about the durability of vaccines, especially the two mRNA products made by Pfizer and Moderna. There is no doubt that immunity declines with the Pfizer vaccine, but by how much, and whether this will result in increased transmission of the coronavirus and more hospitalizations, is unclear. The data for the Moderna vaccine is even more hazy, although it seems to hold up better than Pfizer’s.

Scientists and health officials have stressed that the request for boosters is not a signal of vaccine failure. But if a third blow prevents a new wave of cases – and in turn an increase in hospitalizations that would test already overburdened health systems – it seems a relatively simple tactic, said Dr Jorge Salinas, expert in infectious diseases at Stanford. .

“We are currently at the tipping point in hospitals. And I think that’s why public health officials say, “Hey, let’s do what we can,” Salinas said. “Even a smaller wave can have a huge impact. “

Coronavirus cases have already started to increase in parts of the country and to increase hospitalizations as well. Cases have risen slightly in California, but hospitalizations are still down since the summer delta surge.

Many scientists are still not convinced that boosters are necessary for everyone, especially in highly vaccinated places like much of the Bay Area, but they generally agree that the extra doses won’t hurt. And for healthy young and middle-aged adults, boosters should reduce their chances of getting infected and, in turn, reduce community transmission.

“Personally, I feel very conflicted about the boosters,” said Nadia Roan, a researcher at the Gladstone Institutes in San Francisco, who studies vaccine-induced immunology. She said the evidence so far has not convinced her that boosters are needed and that she would prefer doses of the vaccine to be sent to areas of the world that do not have access to them. But she recognizes that boosters are likely to at least marginally improve protection.

It’s also still unclear how many boosters people might need and how often. It’s possible, some scientists say, that COVID vaccines work best with three doses – or two, in the case of Johnson & Johnson – to achieve maximum effectiveness. Or the reminders can become an annual ritual, much like the flu shots.

COVID vaccines trigger two broad immune responses: antibodies, which are the frontline fighters that almost immediately oppose the virus, and immune cells which take longer to respond but aggressively attack infection and prevent serious illness.

It appears so far that the cellular immune response remains robust for all three types of vaccines, even several months after full vaccination. But the antibodies drop considerably, which is to be expected; the antibodies usually do not linger in the body.

This does mean, however, that post-vaccination infections become more frequent as antibody immunity wanes. This played out particularly vividly during the delta surge, when many people arrived six months after vaccination at the same time that a particularly infectious variant dominated.

Health officials now fear that the drop in immunity will be even more of a problem this winter, as more people come inside, travel and congregate for the holidays. They do not anticipate a wave like that of last winter, when vaccines were just starting to be administered. And it is very likely that a spike in cases would not lead to a similar increase in serious illnesses requiring hospitalization.

But some officials fear that widespread winter transmission could threaten those who remain vulnerable to severe disease, especially those who have not yet been vaccinated.

There is strong evidence that vaccine protection against serious illness wanes, in some cases significantly, in people 65 years of age and older or those with underlying health conditions. These people have been urgently urged for boosters, but adoption so far has been slow – less than half of people 65 and over have received statewide boosters for two months.

At a vaccination clinic in San Francisco’s Ingleside neighborhood on Friday said they were relieved to have easy access to reminders, after being frustrated by confusion over whether they were approved. for the third injections and where to get them.

Shirley Foreman, 73, said she was able to get an appointment with her supplier but had to call multiple times to confirm she was eligible and then the first date they were able to schedule her was early December. She wanted to be stimulated before Thanksgiving, when she plans to volunteer at a community dinner.

“It was so much chaos,” said Foreman, shortly after being shot at New Providence Baptist Church. “I’m just happy that I can get it. I feel safe now.

Erin Allday is a writer for the San Francisco Chronicle. Email: [email protected] Twitter: @erinallday

Source link