US authorizes COVID-19 boosters for all adults, recommends for over-50s

The United States authorized the Pfizer and Moderna COVID-19 vaccine boosters for all people aged 18 and older on Friday, as the world's hardest-hit country enters a new winter wave of the pandemic.

Boosters were previously available to the immunocompromised, people over 65, those at high risk of severe disease, and people in high risk occupations.

The new decision "helps to provide continued protection against COVID-19, including the serious consequences that can occur, such as hospitalization and death," acting commissioner Janet Woodcock of the Food and Drug Administration (FDA) said.

A panel of experts convened by the Centers for Disease Control and Prevention (CDC) then ratified the decision to broaden eligibility, while explicitly recommending boosters for all people over 50, even absent underlying conditions.

"I am really glad that we have clarity and streamlining of the recommendations so that all Americans can understand the vaccines that are recommended for them at this time," said Camille Kotton, an infectious disease clinician at Massachusetts General Hospital.

CDC director Rochelle Walensky formally signed off on the panel's recommendations, stating that boosters "are an important public health tool to strengthen our defenses against the virus as we enter the winter holidays."

The FDA said it based its decision on data demonstrating a strong immune response to boosters from hundreds of people dosed with both brands of vaccines. 

Pfizer also carried out a clinical trial involving 10,000 people aged over 16 which found that the booster showed an efficacy against symptomatic infection of more than 95 percent compared to those who did not receive a booster.

Both vaccines are available to people six months after completing their primary series. 

Pfizer's vaccine is dosed at 30 micrograms, the same as the primary series, while Moderna's is 50 micrograms, half the primary series.

People who received the Johnson & Johnson one-dose vaccine were already eligible for a booster of any brand two months after their first shot.

The booster decision comes as cases are rapidly rising nationally, reaching 88,000 new infections per day on average as the country enters its fifth wave, according to the latest data. 

America is officially the pandemic's hardest-hit country, with more than 760,000 deaths.

Many unknowns 

Prior to Friday's decision, some outside experts had expressed misgivings over widening boosters to all adults.

The vast majority of those people becoming hospitalized or dying with COVID are unvaccinated, and the best way to control the winter wave would be to reach those people, rather than topping up the vaccinated, the critics said.

A potential downside, they argued, was that vaccine holdouts might conclude the shots are ineffective. 

Another risk is a greater number of cases of vaccine-linked heart inflammation (myocarditis), especially among younger males. Accumulating evidence shows the risk may be greater for the Moderna vaccine compared to Pfizer, likely because of its higher dose.

Both companies are conducting post-authorization studies to assess the risks of myocarditis after third shots.

Overall, however, both health agencies took the view that the benefits outweigh the risks.

It is expected that boosters, by reducing symptomatic cases, will also help reduce community transmission, though the extent to which this might happen is not known.

It is also possible that, rather than considering the third dose a booster, the vaccines work optimally when administered three times— something that will become more clear over time as data accrues. 

Experts are in broad agreement, however, that boosters alone can't resolve the pandemic while the poorest countries, especially in Africa, remain stuck in the single-digit percentages for people covered by their initial shots. 

Last week, WHO chief Tedros Adhanom Ghebreyesus decried the fact that rich countries are administering six times more vaccine doses every day than low-income countries are delivering primary doses.

This increases the risk of new variants of concern emerging in those regions, which could eventually evade the protective action of current vaccines.

Agence France-Presse

Virus vaccine put to final test in thousands of volunteers

The world’s biggest COVID-19 vaccine study got underway Monday with the first of 30,000 planned volunteers helping to test shots created by the U.S. government -- one of several candidates in the final stretch of the global vaccine race.

There’s still no guarantee that the experimental vaccine, developed by the National Institutes of Health and Moderna Inc., will really protect.

The needed proof: Volunteers won’t know if they’re getting the real shot or a dummy version. After two doses, scientists will closely track which group experiences more infections as they go about their daily routines, especially in areas where the virus still is spreading unchecked.

“Unfortunately for the United States of America, we have plenty of infections right now” to get that answer, NIH’s Dr. Anthony Fauci recently told The Associated Press.

Moderna said the vaccination was done in Savannah, Georgia, the first site to get underway among more than seven dozen trial sites scattered around the country.

In Binghamton, New York, nurse Melissa Harting said she volunteered as a way “to do my part to help out.”

“I’m excited,” Harting said before she received a study injection Monday morning. Especially with family members in front-line jobs that could expose them to the virus, “doing our part to eradicate it is very important to me.”

Several other vaccines made by China and by Britain’s Oxford University began smaller final-stage tests in Brazil and other hard-hit countries earlier this month.

But the U.S. requires its own tests of any vaccine that might be used in the country and has set a high bar: Every month through fall, the government-funded COVID-19 Prevention Network will roll out a new study of a leading candidate -- each one with 30,000 newly recruited volunteers.

The massive studies aren’t just to test if the shots work — they’re needed to check each potential vaccine’s safety. And following the same study rules will let scientists eventually compare all the shots.

Next up in August, the final U.S. study of the Oxford shot begins, followed by plans to test a candidate from Johnson & Johnson in September and Novavax in October -- if all goes according to schedule. Pfizer Inc. plans its own 30,000-person study this summer.

That’s a stunning number of people needed to roll up their sleeves for science. But in recent weeks, more than 150,000 Americans filled out an online registry signaling interest, said Dr. Larry Corey, a virologist with the Fred Hutchinson Cancer Research Institute in Seattle, who helps oversee the study sites.

“These trials need to be multigenerational, they need to be multiethnic, they need to reflect the diversity of the United States population,” Corey told a vaccine meeting last week. He stressed that it’s especially important to ensure enough Black and Hispanic participants as those populations are hard-hit by COVID-19.

It normally takes years to create a new vaccine from scratch, but scientists are setting speed records this time around, spurred by knowledge that vaccination is the world’s best hope against the pandemic. The coronavirus wasn’t even known to exist before late December, and vaccine makers sprang into action Jan. 10 when China shared the virus’ genetic sequence.

Just 65 days later in March, the NIH-made vaccine was tested in people. The first recipient is encouraging others to volunteer now.

“We all feel so helpless right now. There’s very little that we can do to combat this virus. And being able to participate in this trial has given me a sense of, that I’m doing something,” Jennifer Haller of Seattle told the AP. “Be prepared for a lot of questions from your friends and family about how it’s going, and a lot of thank-you’s.”

That first-stage study that included Haller and 44 others showed the shots revved up volunteers’ immune systems in ways scientists expect will be protective, with some minor side effects such as a brief fever, chills and pain at the injection site. Early testing of other leading candidates have had similarly encouraging results.

If everything goes right with the final studies, it still will take months for the first data to trickle in from the Moderna test, followed by the Oxford one.

Governments around the world are trying to stockpile millions of doses of those leading candidates so if and when regulators approve one or more vaccines, immunizations can begin immediately. But the first available doses will be rationed, presumably reserved for people at highest risk from the virus.

“We’re optimistic, cautiously optimistic” that the vaccine will work and that “toward the end of the year” there will be data to prove it, Dr. Stephen Hoge, president of Massachusetts-based Moderna, told a House subcommittee last week.

Until then, Haller, the volunteer vaccinated back in March, wears a mask in public and takes the same distancing precautions advised for everyone -- while hoping that one of the shots in the pipeline pans out.

“I don’t know what the chances are that this is the exact right vaccine. But thank goodness that there are so many others out there battling this right now,” she said.

Associated Press

AP photographer Ted Warren in Seattle contributed to this report.