Vaccinations against COVID-19 are at a critical time as companies test whether new approaches like combination shots or nose drops can keep up with a mutating coronavirus – although it’s unclear if any changes are needed .
There is already public confusion about who should get a second recall now and who can wait. There’s also some debate about whether just about everyone might need an extra dose in the fall.
“I am very concerned about recall fatigue” causing a loss of faith in vaccines that still offer very strong protection against the worst outcomes of COVID-19, said Dr. Beth Bell of the University of Washington, adviser from the United States Centers for Disease Control. and Prevention.
Despite the success in preventing serious illness and death, there is growing pressure to develop vaccines better able to fend off milder infections, as well as options to counter the scary variants.
‘We go through a fire drill, it seems like every quarter, every three months or so’ when another mutant provokes frantic tests to determine if the shots are holding up, said Pfizer’s head of vaccines Kathrin Jansen , at a recent meeting of the New York Academy of Sciences.
Still, chasing improvements for the next round of vaccinations may seem like a luxury for American families concerned about protecting their youngest children — children under age 5 who aren’t yet eligible for a vaccine. Moderna’s Dr. Jacqueline Miller told The Associated Press that her request for two low-dose injections to be given to younger children would be submitted to the Food and Drug Administration “fairly soon.” Pfizer has yet to release data on a third dose of its very small vaccine for toddlers, after two were found not to be strong enough.
COMBINED PLANS CAN BE FOLLOWING
The original COVID-19 vaccines remain strongly protective against severe illness, hospitalization, and death, especially after a booster dose, even against the most contagious variants.
Updating the vaccine recipe to match the latest variants is risky, as the next mutant could be completely unrelated. Companies are therefore taking inspiration from the flu vaccine, which offers protection against three or four different strains in a single injection each year.
Moderna and Pfizer are testing the 2-in-1 COVID-19 protection they hope to deliver this fall. Each “bivalent” injection would mix the proven original vaccine with an omicron-targeted version.
Moderna has a hint that the approach might work. He tested a combination shot that targeted the original version of the virus and an earlier variant named beta – and found that vaccine recipients developed modest levels of antibodies capable of fighting not only beta but newer mutants like omicron. Moderna is currently testing its targeted bivalent candidate omicron.
But there is an impending deadline. The FDA’s Dr. Doran Fink said if updated injections were to be given in the fall, the agency should decide on a recipe change in early summer.
DON’T EXPECT BOOSTERS EVERY MONTH
For the average person, two doses of the Pfizer or Moderna vaccine plus a booster — a total of three injections — “prepare you” and prepare you for what could become an annual booster, said Dr. David Kimberlin, a CDC adviser from the University of Alabama at Birmingham.
After this first booster, CDC data suggests that an extra dose provides most people with additional, temporary benefit.
Why the emphasis on three strokes? Vaccination triggers the development of antibodies which can ward off coronavirus infection but naturally decline over time. The next line of defense: memory cells that spring into action to make new virus fighters if an infection sneaks up. Rockefeller University researchers found that these memory cells become more powerful and able to target more diverse versions of the virus after the third hit.
Even if a vaccinated person gets a mild infection, thanks to these memory cells, “there’s still plenty of time to protect you from serious illness,” said Dr. Paul Offit of Children’s Hospital of Philadelphia.
But some people – those with severely weakened immune systems – need more doses up front for the best chance of protection.
And Americans 50 and older are being offered a second booster, following similar moves by Israel and other countries that offer the extra kick to give the elderly a bit more protection.
The CDC is developing guidance to help eligible people decide whether to get an additional injection now or wait. Among those who might want a second booster sooner are the elderly, people with health conditions that make them particularly vulnerable, or who are at high risk of exposure at work or while traveling.
COULD NASAL VACCINES BLOCK INFECTION?
It’s hard for a shot in the arm to form many anti-virus antibodies inside the nose where the coronavirus latches. But a nasal vaccine could offer a new strategy to prevent infections that disrupt people’s daily lives, even if they are mild.
“When I think about what would get me a second booster, I would actually want to prevent infection,” said Dr. Grace Lee of Stanford University, who chairs the CDC’s immunization advisory committee. “I think we have to do better.”
Nasal vaccines are difficult to develop and it is unclear how quickly they might become available. But several are in clinical trials around the world. One in advanced testing, made by India’s Bharat Biotech, uses a chimpanzee cold virus to deliver a harmless copy of the coronavirus’ spike protein to the lining of the nose.
“I certainly don’t want to give up on the success we’ve had” with COVID-19 injections, said Dr. Michael Diamond of Washington University in St. Louis, who helped create the candidate who is now fired. in Bharath.
But “we’re going to have a hard time stopping transmission with current systemic vaccines,” Diamond added. “We all learned that.”
The Associated Press Health and Science Department is supported by the Howard Hughes Medical Institute Department of Science Education. The AP is solely responsible for all content.