US health authorities will presumably soon recommend boosters for the COVID-19 vaccine to Americans who have completed their vaccination schedule.
Here’s a look at what we know about the boosters and how they might help fight coronavirus:
___
WHY MIGHT WE NEED REINFORCEMENTS?
It is normal for the protection of vaccines to decrease over time. For example, a tetanus booster is recommended every 10 years.
Researchers and health officials have been monitoring the performance of COVID-19 vaccines in the real world to see how long they protect those vaccinated. Vaccines licensed in the United States continue to offer strong protection against severe illness and death.
But some blood tests have indicated that antibodies, one of the protective layers of the immune system, can decrease over time. This does not mean that the protection is gone, but it may mean that the protection is not as strong or that it may take longer for the body to fight an infection.
The delta variant has complicated the question of when to administer boosters because it is much more contagious and because much of the data collected on vaccine performance predates the variant being widely circulated. The spread of the delta variant is skyrocketing at the same time that immunity may be declining among the first vaccinated people.
Israel offers a booster for people over 50 who were vaccinated more than five months ago. France and Germany plan to offer reinforcements to some people within a few months. The European Medicines Agency also said it analyzes data to see if the boosters are necessary.
___
WHEN WOULD THEY BE ADMINISTERED?
It depends on when the initial doses were received. One possibility is that authorities recommend that people receive a booster approximately eight months after receiving the second dose of the Pfizer or Moderna vaccines.
Authorities are still collecting information on Johnson & Johnson’s single-dose vaccine, which was approved in the United States in late February, to determine when to recommend boosters.
___
WHO WOULD RECEIVE THEM?
The first people to be vaccinated in the United States will likely also be the first for boosters. That means healthcare workers, shelter residents and other older Americans, who were the first to get vaccinated when vaccines were authorized last December.
___
REINFORCEMENT? THIRD DOSE? WHAT IS THE DIFFERENCE?
Transplant recipients and other people with weakened immune systems may not have received enough protection from vaccines early on. They can now receive a third dose at least 28 days after their second dose as part of their initial vaccination series. For those with normal immune systems, boosters are given long after full vaccination, not to generate protection, but to reactivate it.
___
WHAT DOUBTS EXIST?
It is still unknown whether people should receive the same type of vaccine that was given to them when they were first vaccinated. And the nation’s top health advisers will look for evidence on the safety of boosters and how well they protect against infection and severe disease.
Global access to vaccines is also important to contain the pandemic and prevent new variants from emerging. The boosters could be a problem for already scarce global vaccine supplies.
___
AND THOSE WHO HAVE NOT BEEN VACCINATED?
Dr. Melanie Swift, who has led the vaccination program at the Mayo Clinic in Rochester, Minnesota, says that vaccinating more people who still do not have a dose is “our best tool, not only to prevent hospitalization and mortality from the disease. delta variant, but to stop the transmission ”. Each infection “gives the virus more chances to mutate who knows what the next variant will be.”
“People who got the vaccine the first time are likely to train to get the booster,” Swift said. “But we are not going to achieve our overall goals if their neighbors are not vaccinated.”
___
The Associated Press Department of Health and Science receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.
–
