The latest on Covid-19 boosters in the US

US Centers for Disease Control and Prevention Director Dr. Rochelle Walensky endorsed recommendations for booster doses for Moderna’s and Johnson & Johnson’s coronavirus vaccines Thursday evening, clearing the way for millions more Americans to get booster shots. Some adults were already eligible to get booster shots of Pfizer’s Covid-19 vaccine.

Currently Pfizer’s and Moderna’s Covid-19 boosters are authorized for those 65 and older as well as those 18 and older who live in long-term care settings, have underlying medical conditions or who work or live in high-risk settings. 

A booster of Johnson & Johnson is recommended two months after vaccination for everyone 18 and older.

While speaking to NBC’s "Today" Friday morning, Walensky was asked about expanding booster eligibility to people as young as 40. 

Asked by NBC’s Savannah Guthrie if those who fell outside of the eligible categories should be worried about waning immunity, Walensky said “I don’t think that there’s reason to be concerned now.” She added “Our vaccines are still working really well against severe disease, hospitalization and death.

Walensky also recommended that people follow prevention measures as there is “a lot of disease out there.” She said the CDC will continue to follow any data that demonstrates if and when there is waning protection for people who are generally healthy. 

In new documents posted ahead of a key meeting of the US Food and Drug Administration’s vaccine advisers, Pfizer says its vaccine is safe and 90.7% effective against symptomatic Covid-19 in children ages 5 to 11.

In the trial, which included around 2,000 children, there were three Covid-19 cases among the group that received the vaccine and 16 cases in the placebo group. In the trial, twice as many children received the vaccine as the placebo.

Pfizer/BioNTech are seeking FDA emergency use authorization (EUA) of a two-dose regimen of their 10-microgram dose for children ages 5 to 11. The two doses would be administered three weeks apart.

Last month, Pfizer released details of a Phase 2/3 trial that showed its Covid-19 vaccine was safe and generated a "robust" antibody response in children ages 5 to 11. The trial included 2,268 participants ages 5 to 11. Participants' immune responses were measured by looking at neutralizing antibody levels in their blood and comparing those levels to a control group of 16- to 25-year-olds who were given a two-dose regimen with the larger 30-microgram dose. Pfizer said the levels compared well with older people who received the larger dose, demonstrating a "strong immune response in this cohort of children one month after the second dose."

The FDA’s Vaccines and Related Biological Products Advisory Committee is scheduled to meet Oct. 26 to discuss whether to recommend the vaccine for authorization for those ages 5 to 11.

If authorized, this would be the first Covid-19 vaccine for younger children. The Pfizer/BioNTech vaccine is approved for people age 16 and older and has an EUA for people ages 12 to 15.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told CNN’s John Berman that while it makes sense to get a booster shot that is the same as the original vaccine series, it’s also OK to mix and match. 

Some background: US Centers for Disease Control and Prevention Director Dr. Rochelle Walensky endorsed recommendations for booster doses for Moderna’s and Johnson & Johnson’s coronavirus vaccines Thursday evening, which cleared the way for millions more Americans to get booster shots. Some adults were already eligible to get booster shots of Pfizer’s Covid-19 vaccine.

The authorization process for Covid-19 vaccines can get confusing. Here’s a look at where we stand on Covid-19 boosters in the US today:

Pfizer

In September, the US Food and Drug Administration and US Centers and Disease Control and Prevention signed off on boosters of the Pfizer/BioNTech Covid-19 vaccine for adults 65 and older, adults at high risk of severe Covid-19 and adults with frequent exposure to the coronavirus through their work. Those boosters were authorized only for people who had already received the Pfizer vaccine at least six months earlier. 

On Wednesday, US Centers for Disease Control and Prevention Director Dr. Rochelle Walensky endorsed the mix-and-match approach to boosters, meaning the Pfizer/BioNTech booster can be taken by those who may be eligible but are fully vaccinated with either the Moderna or Johnson & Johnson coronavirus vaccines.

Additionally, next week, vaccine advisers to the FDA are scheduled to meet next week to consider Pfizer's request to authorize its vaccine to children ages 5 to 11.

Moderna

The FDA gave emergency use authorization on Wednesday for a half dose of Moderna's vaccine as a booster for people fully vaccinated at least six months ago who are also at least 65, or who are at least 18 and at high risk of severe Covid-19 or have frequent institutional or occupational exposure to the virus.

Walensky endorsed a recommendation for booster doses for the Moderna vaccine on Thursday.

Johnson & Johnson

On Wednesday, the FDA authorized booster doses of Johnson & Johnson’s vaccine for anyone who received It at least two months ago. The J&J vaccine authorized only for those 18 and older.

The company announced last month that a two-dose version of the vaccine provides 94% protection against symptomatic infection.

Walensky endorsed a recommendation for booster doses for the Johnson & Johnson vaccines on Thursday.

Mixing and matching boosters

The FDA said any of the three authorized vaccines could be used as a booster in a "mix-and-match" approach.

Dr. Peter Marks, director of the FDA's vaccine arm, the Center for Biologics Evaluation and Research, said the ability to use any authorized vaccine as a booster will simplify matters for people.

The FDA said it decided to allow the mix-and-match boosters after National Institutes of Health researchers presented their findings last week to its vaccine advisers. Although the findings were limited, they made it clear mixing up the different vaccines was safe.

Walensky also endorsed the mix-and-match approach to boosters, saying eligible people could choose whichever vaccine they wished as a booster.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said he is confident that within the next weeks to months, the age of people eligible to get a Covid-19 booster will be lowered.  

Fauci said that more data would come from both US cohorts and from cohorts in Israel. 

Asked about how much evidence of waning immunity for people with two doses is being seen, Fauci said, “there’s no question about that, John, that that occurs.” 

He added that it has been seen in US cohorts as well as in Israel, which is about a month ahead of the US in its timetable and “is seeing substantial waning of immunity over several months, first against infection and then in some age groups against severe disease.” 

This is the reason why boosters are being given, he said, and why Israel, as an example, is “much, much more proactive in giving boosters for people.” 

The director of the US Centers for Disease Control and Prevention, Dr. Rochelle Walensky, signed off yesterday on booster shots for some Americans who received the Moderna and Johnson & Johnson vaccines. Last month, she did the same for some people who have receive the Pfizer vaccine.

Here's who is eligible for booster shots in the US now:

For people who got a Pfizer-BioNTech or Moderna Covid-19 vaccine, only some groups of people are eligible for a booster shot six months or more after they got their second initial dose, the CDC said.

They include people who are:

For Americans who got the Johnson & Johnson Covid-19 vaccine, booster shots are recommended for people who are 18 and older and who got their single first shot two or more months ago.

US Centers for Disease Control and Prevention Director Dr. Rochelle Walensky endorsed recommendations for booster doses for Moderna's and Johnson & Johnson's coronavirus vaccines Thursday, allowing millions more Americans to begin getting booster shots.

Walensky also endorsed the mix-and-match approach to boosters, saying eligible people could choose whichever vaccine they wished as a booster.

The CDC re-aligned its recommendation for the existing recommendation for Pfizer boosters, placing Moderna's and Pfizer's boosters in the same category.

"For individuals who received a Pfizer-BioNTech or Moderna COVID-19 vaccine, the following groups are eligible for a booster shot at 6 months or more after their initial series," it said.

They include people:

"For the nearly 15 million people who got the Johnson & Johnson COVID-19 vaccine, booster shots are also recommended for those who are 18 and older and who were vaccinated two or more months ago," it added.

The CDC's Advisory Committee for Immunization Practices had just hours earlier voted to accept the US Food and Drug Administration emergency use authorizations for each vaccine – after considerable discussion about whether such broad authorization was needed for Moderna's.

Members agreed that people who got Johnson & Johnson's vaccine need a second vaccination, as that vaccine is less effective than Moderna's and Pfizer's in preventing infection.

"There are now booster recommendations for all three available COVID-19 vaccines in the United States," the CDC said.

"Eligible individuals may choose which vaccine they receive as a booster dose," it added.

"Some people may have a preference for the vaccine type that they originally received and others, may prefer to get a different booster. CDC's recommendations now allow for this type of mix and match dosing for booster shots."

Already, the pace of Americans getting booster doses is higher than the rate of those being vaccinated for the first time. CDC officials and others have made it clear the best way to reduce spread of the coronavirus is to get more people vaccinated in the first place.

"Millions of people are newly eligible to receive a booster shot and will benefit from additional protection. However, today's action should not distract from the critical work of ensuring that unvaccinated people take the first step and get an initial COVID-19 vaccine. More than 65 million Americans remain unvaccinated, leaving themselves — and their children, families, loved ones, and communities — vulnerable," the CDC said in Thursday's statement.

"Available data right now show that all three of the COVID-19 vaccines approved or authorized in the United States continue to be highly effective in reducing risk of severe disease, hospitalization, and death, even against the widely circulating Delta variant. Vaccination remains the best way to protect yourself and reduce the spread of the virus and help prevent new variants from emerging."

CDC officials said they'd issue more guidance on boosters in an upcoming report.

Read more about the CDC's decision here.