Faced right now with growing evidence that our vaccines are losing their edge to fight off the highly contagious delta variant, the anxious inoculated are asking: Why wait?
On Thursday, health officials began planning “booster” distribution systems that are expected to be less chaotic than last spring’s historic crush, with larger vaccine supplies and a more orderly flow of eligible patients routed to doctor’s offices, pharmacies and clinics.
But they are prohibited from giving third shots now, even with growing evidence of “breakthrough” infections.
The California Department of Public Health and counties say they are waiting for review and approval by the U.S. Food and Drug Administration and the U.S. Centers for Disease Control and Prevention, as well as the Western States Scientific Safety Review Workgroup. That isn’t expected until the week of Sept. 20.
“We’ll have to adhere to their guidelines,” said Dr. Jennifer Tong, Associate Chief Medical Officer at Santa Clara Valley Medical Center.
While third doses already are being given to people who are immunocompromised, next month’s plan for the rest of us will be very different, she said.
“It’s a whole different category. These are true ‘booster’ shots,” given to the general population, so will receive more rigorous regulatory scrutiny, said Tong. The shots will be restricted to those who received their second dose of Pfizer or Moderna vaccine eight months ago. It’s not yet known what will be approved for those who received the Johnson & Johnson vaccine.
The White House’s decision about boosters came earlier than some experts expected, said Julie Swann, an industrial and systems engineering professor at North Carolina State University who studies pandemic responses and was an adviser to the CDC during the 2009 H1N1 outbreak.
The logistics are complicated because of the varying needs of different populations, she said. “Providers and health jurisdictions will simultaneously be giving the vaccine to some people for the first time, some for boosters based on previous date of shot — and, hopefully at some point, children ages five to 11.”
Frontline health care workers likely will be the first to be eligible for booster shots, she said.
Officials need to take stock of their inventories to make sure they have adequate supplies — and, if not, will need to order more vaccines, said Tong. But they can’t stockpile large volumes of doses indefinitely, because vaccines expire.
Unlike earlier in the pandemic, there are no shortages of vaccines. Pfizer, for example, announced in late July that the federal government had purchased an additional 200 million doses of its vaccine.
But distribution “won’t be to everybody at exactly the same time,” said Dr. Lisa Winston, hospital epidemiologist at Zuckerberg San Francisco General Hospital. “There will have to be some kind of a rolling process.”
Despite anxiety over potential infection, it’s not dangerous for fully vaccinated people to wait a little longer for a booster, said Dr. Bali Pulendran, professor of microbiology and immunology at Stanford University School of Medicine.
“It’s just a question of three or four weeks. There’s unlikely to be any substantial decline of the immune response in just 28 days,” he said. “If I had to wait till a year from now, I’d be worried. But I’m not too worried about the fact that it’s the week of September 20 and not today.”
In the weeks following the second dose of the vaccine, levels of antibodies soar, he said. Then, over the next six to eight months, they slowly decline. A booster sends antibody levels climbing ten-fold — as high, or perhaps higher, as seen after the second dose.
“The immune response shoots up like a rocket, then glides down. Imagine the space shuttle, on a slow glide path. It doesn’t come crashing down” leaving us suddenly vulnerable, said Pulendran.
Immunologists hope that the booster will provide a more durable protection than the first and second doses.
“The basic principle is that the immune response always tends to be larger and stronger and more longer lasting with a booster dose,” said Pulendran.
Additional shots beyond the first booster, without evidence of waning immunity, are not needed, according to Winston and Pulendran.
“There would be diminishing returns. It just wouldn’t be necessary or helpful, and so it would not be a good use of resources,” said Winston, who hopes instead that the U.S. will share extra doses to the international community.
In addition, there is emerging evidence that each extra dose triggers the same mild to moderate side effects experienced after the second dose — so, if not needed, boosters could cause unnecessary absence from work or school.
The booster shot won’t be tweaked for variants; it’s identical to the first two shots. Any changes to its formulation don’t fit in the timeframe laid out by the White House — and wouldn’t be authorized without a new round of thorough testing. However, both Pfizer and Moderna are conducting research on a booster that’s designed to tackle specific variants. Johnson & Johnson is studying using their original dose in a two-dose series given 56 days apart.
While waiting, it is important for people to continue to protect themselves through other measures, such as masking, said health experts.
“The announcement gives communities some time to figure out the best distribution options to meet their needs,” Swann said. “They will need some time to determine the best channels in their community.”
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August 20, 2021 at 11:17PM
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If we need it — why wait for the COVID vaccine booster? - Woodland Daily Democrat
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