in a rush of federal action, two of the main health agencies in the country authorized and expanded eligibility for the COVID-19 vaccine to allow older Americans to get a second booster shot.
On Tuesday, the Food and Drug Administration authorized a second dose of Pfizer-BioNTech or Moderna for people 50 and older at least four months after the first.
The Centers for Disease Control and Prevention signed the authorization several hours later.
Agency Director Dr. Rochelle Walensky said additional bracing is especially important for people over 65, and for people over 50 who have underlying medical conditions that increase the risk of severe illness from COVID. -19.
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“They are more likely to benefit from receiving an additional booster dose at this time,” he said in a statement.
Here’s what you should know about booster shots:
Who can get a second COVID booster of Pfizer or Moderna vaccines?
Anyone over the age of 50 who has received an approved or licensed primary COVID-19 vaccine series and a booster dose is eligible for a second booster from Pfizer-BioNTech or Moderna at least four months after receiving the first.
Although the CDC expanded booster eligibility, the agency says the second shot is especially important for people over 65 and people over 50 with underlying medical conditions.
Anyone who is immunocompromised and older than 12 years is eligible for another dose of the Pfizer-BioNTech vaccine, and immunocompromised adults can now also receive the Moderna vaccine.
For the immunocompromised, the initial vaccination course is three doses. They have been allowed since last fall to receive a first booster, or a fourth dose, and are now entitled to a fifth, CDC spokeswoman Kristen Nordlund confirmed.
What qualifies as an “underlying medical condition”?
Studies have shown that people who have certain medical conditions are at higher risk of developing severe illness from COVID-19, According to the Centers for Disease Control and Prevention.
These medical conditions include obesity, diabetes, chronic lung, kidney, or liver disease, heart disease, smoking, pregnancy, and many mental health conditions.
The CDC completed a review of each medical condition to make sure it met the criteria for listing, but urges people to talk to their health care provider about their risk, as some medical conditions may not be listed. appear on the list.
Can people who received a Johnson & Johnson vaccine get a second booster?
People who received initial doses of the Johnson & Johnson vaccine may receive a second booster dose, Nordlund said. The J&J vaccine was initially a single shot vaccine, although studies suggested that two doses were needed to provide the same protection as the other two licensed vaccines.
J&J recipients have been eligible since last fall to receive a second shot, and the CDC has recommended that they receive an mRNA vaccine for their second dose. They can get a third injection with either Pfizer-BioNTech or Moderna, Nordlund said.
Where can you get a second COVID booster?
The country’s two main pharmacies say they are preparing to administer second booster doses to eligible recipients this week.
A CVS spokesperson told USA TODAY that eligible patients will “soon” be able to schedule the additional injection online or through the pharmacy app, but did not specify when people can make their appointment.
Walk-in appointments at the Walgreens Pharmacy are available Wednesday through Friday, “as store capacity allows,” a spokesperson said. Appointment scheduling at Walgreens will be available online or through the mobile app beginning Friday.
The Biden administration is also launching a comprehensive online hubCOVID.gov, which will allow people to access pharmacies and quickly find information about COVID vaccines.
What does the data say about a fourth dose of the COVID vaccine?
There is no data to suggest that healthy people will benefit significantly from a fourth dose or how long the fourth dose will last.
But some data suggests that a second booster shot might help combat the decline in immunity after the third shot.
The FDA cited an ongoing study among Israeli healthcare workers, 154 of whom received a fourth injection with the Pfizer-BioNTech vaccine and 120 who received a second booster with Moderna.
Two weeks later, both groups saw at least a tenfold increase in antibody levels capable of fighting COVID-19, while antibody levels continued to drop among those who did not receive an additional booster. No new safety concerns were raised in either group.
Other studies, some not peer-reviewed and officially published, show that vaccine effectiveness declines three to six months after the initial booster, and a second booster may improve protection against serious illness.
Contributor: Karen Weintraub and Michael Collins, USA TODAY. Follow Adrianna Rodriguez on Twitter: @AdriannaUSAT.
Coverage of patient health and safety on USA TODAY is made possible in part by a grant from the Masimo Foundation for Ethics, Innovation and Competition in Health Care. The Masimo Foundation does not provide editorial input.