Reading, PA, April 25 (BUS): COVID-19 vaccinations are at a critical stage as companies test whether new methods such as combination shots or nasal drops can keep pace with the changing coronavirus – although it’s not clear if changes are needed .
There is already general confusion about who should get a second booster now and who can wait. There is also controversy over whether everyone might need an extra dose in the fall, the AP reports.
“I am very concerned about the enhanced fatigue” that is causing a loss of confidence in vaccines that still provide very strong protection against the worst outcomes of COVID-19, said Dr. Beth Bell of the University of Washington, an advisor to the US Centers for Disease Control. and prevention.
Despite success in preventing serious illness and death, there is growing pressure to develop better vaccines to stave off milder infections as well — as well as options to counter dreaded variables.
“We do a fire drill that looks like every three months or every three months or so” when another mutant causes frantic tests to determine if the shots are in place, Katherine Janssen, head of Pfizer’s vaccine, said at a recent meeting of the New York Academy of Sciences.
Still, looking for improvements in the next round of vaccinations may seem like a luxury to American families eager to protect their young children — children under five who are not yet eligible for an injection. Moderna’s Dr. Jacqueline Miller told The Associated Press that her request to give two lower doses to younger children will be submitted to the Food and Drug Administration “fairly soon.” Pfizer has not yet reported data on a third dose of the very small shot for young children, after two were not proven strong enough.
Compound shots may be then
The original COVID-19 vaccines remain powerfully protective against serious illness, hospitalization, and death, especially after a booster dose, even against the most infectious variants.
Updating the vaccine prescription to match the latest variants is risky, because the next mutant may be completely unrelated. So companies take advantage of the flu shot, which provides protection against three or four different strains in one shot each year.
Moderna and Pfizer are testing the 2-in-1 protection against COVID-19 they hope to offer this fall. Each “bivalent” injection will mix the original proven vaccine with a targeted version of Omicron.
Moderna hints that this approach can work. It tested a combined shot that targeted the original version of the virus and an earlier variant called beta — and found that recipients of the vaccine developed modest levels of antibodies capable of fighting not only beta but also newer mutations like Omicron. Moderna is now testing its bivalent filter targeting the omicron.
But there is an imminent deadline. If any updated shots are to be given in the fall, the agency will have to decide to change the prescription by early summer, Dr. Doran Fink of the FDA said.
Don’t expect reinforcements every few months
For the average person, two doses of the Pfizer or Moderna vaccine plus a booster dose — a total of three shots — “gets you ready” and ready for what may become a yearly booster, said Dr. David Kimberlin, a CDC advisor from the Centers for Disease Control and Prevention at the University of Alabama at Birmingham. .
After that first booster, CDC data indicates that an additional dose provides most people with an additional temporary benefit.
Why focus on three shots? Vaccination leads to the development of antibodies that can prevent infection with the coronavirus but naturally fade over time. Next line of defense: memory cells that jump into action to make new fighters viruses if an infection creeps in. The Rockefeller University researchers found that these memory cells become more robust and able to target more diverse copies of the virus after the third shot.
Even if someone who’s vaccinated gets a mild infection, thanks to these memory cells, Dr. Paul Offit, of Children’s Hospital of Philadelphia, said, “there’s still plenty of time to protect you from severe illness.”
But some people – those with severely weakened immune systems – need more doses in advance for a better chance of being protected.
Americans 50 and older are getting a second booster dose, following similar decisions by Israel and other countries introducing an extra dose to give the elderly more protection.
The CDC is developing tips to help eligible people decide whether to get an extra shot now or wait. Among those who may want a second booster dose sooner are the elderly, people with health problems that make them especially vulnerable, or at high risk of exposure to work or travel.
Could it be rhinitis block rhinitis?
It is difficult for a syringe in the arm to make a lot of virus-fighting antibodies inside the nose where the coronavirus sticks. But the nasal vaccine may offer a new strategy to prevent infections that disrupt people’s daily lives, even if they are mild.
“When I think about what would make me get a second booster dose, I actually want to prevent infection,” said Dr. Grace Lee of Stanford University, who chairs the CDC’s Immunization Advisory Committee. “I think we need to do a better job.”
Nasal vaccines are difficult to develop and it is not clear how quickly any of them could be available. But many of them are in clinical trials globally. One late-stage test, made by India’s Bharat Biotech, uses a chimpanzee cold virus to deliver a harmless version of the coronavirus’ spike protein to the lining of the nose.
“I definitely don’t want to give up on the success we’ve had” with the COVID-19 shots, said Dr. Michael Diamond of Washington University in St. Louis, who helped create the now-licensed candidate Bharat.
“We will have difficulty stopping transmission with current systemic vaccines,” Diamond added. “We’ve all learned that.”