As the coronavirus morphs into a tenacious and unpredictable facet of everyday life, scientists and federal health officials are converging on a new strategy to immunize Americans: a vaccination campaign this fall, perhaps with finely-tuned doses. set to combat the version of the virus expected to be in circulation.
The plan would borrow heavily from the manual for distributing annual flu shots and could become the blueprint for arming Americans against the coronavirus in years to come.
But some experts question how well a new vaccination push would be received by a pandemic-weary public, whether doses can be rolled out quickly enough to reach the people who need them most — and whether most Americans need them. additional vaccines.
On June 28, scientific advisers from the Food and Drug Administration will meet to identify the variant of the coronavirus most likely to percolate in the United States as temperatures cool. This should give manufacturers time to decide whether the composition of vaccines needs to be revised and to scale up production, hopefully enough to produce hundreds of millions of doses by October.
FDA scientific advisers said they would favor switching to a newer version of vaccines only if there was compelling evidence that current vaccines were no longer effective and a modified version was found to be better.
The idea is that eligible Americans would be encouraged to get their coronavirus and flu shots at the same time this fall, and in the same places: pharmacies, doctor’s offices, walk-in clinics, etc. Some important details — like who would be eligible — will be ironed out next month at meetings of scientific advisers from the FDA and the Centers for Disease Control and Prevention.
The plan would mark a break with the current sequential authorizations of booster shots for different age groups. But the shortcomings of the annual approach have been apparent to flu researchers for years.
Scientists and federal health officials typically decide on the flu vaccine formulation in the spring, six months before flu season. They guess which version of the flu virus will arrive in the United States by looking at what is already circulating in the southern hemisphere, among other factors.
But some years, “by the time the vaccine is made, the strains have changed, and you might not get a good match,” said Dr. Ofer Levy, director of the precision vaccine program at Boston Children’s. Hospital and Advisor to the FDA. , mentioned.
Among the candidates for a fall Covid vaccine is a booster designed for Omicron, the strange new avatar of the coronavirus, and suits that include it. Moderna’s lead booster candidate contains 25 micrograms each of its original vaccine and one tailored to Omicron, said Dr. Paul Burton, the company’s chief medical officer.
Pfizer is also testing an Omicron-specific vaccine, but won’t make a decision on its candidate in the fall until June, according to company spokeswoman Jerica Pitts.
Even if the vaccine match isn’t perfect, boosting immunity should offer some protection against any new variants in the fall, much like the flu vaccine does.
The number of Americans choosing to receive booster doses has decreased with each new vaccine recommended. While 90% of American adults have received at least one dose of a Covid vaccine, 76% have opted for a second dose and only 50% for a third.
“To consider extra doses for a smaller and smaller return makes it seem like we don’t have a very effective vaccination program,” said Dr. Matthew Daley, principal investigator at Kaiser Permanente Colorado who leads the task force. on vaccines from the CDC.
A national campaign for another vaccination would unnecessarily strain pharmacists, providers and public health staff, Dr Daley and other advisers warned at a meeting of their committee last month.
And experts worry that a push for additional doses this fall, when the risks of serious illness and death are likely low for most Americans, could hurt the collective will to get vaccinated later if a new variant surfaced and that the public urgently needs this.
Repeated immunizations can even reduce the effectiveness of a vaccine. For example, people who are vaccinated against the flu in a single year develop stronger immunity than those who are vaccinated two years in a row, noted Florian Krammer, an immunologist at the Icahn School of Medicine at Mount Sinai in New York.
Despite apprehensions, federal officials are gearing up for a fall campaign. Tying the Covid vaccine to the flu every year is the easiest way to convince Americans to line up for vaccines, said Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research.
“It saves people time,” Dr. Marks said. “And that may mean more people getting both vaccines, which would be a good thing.”
Agency scientists are actively debating the best composition for a fall vaccine with the World Health Organization, National Institutes of Health and vaccine makers, Dr Marks said.
The FDA favors offering roughly the same formulations as the Pfizer-BioNTech and Moderna vaccines, to avoid confusing people. Otherwise, “I’m afraid it will actually cripple a vaccination campaign, when the most important thing is that people are stimulated,” Dr Marks said.
If the flu shot is any indication, however, many Americans will forego another Covid vaccine. The Omicron variant has made it clear that preventing all infections is an elusive goal, and many only consider themselves at low risk of serious illness or death.
Yet Dr. Marks noted that flu campaigns are also about preventing lost productivity, not just the medical consequences.
Before the arrival of the Omicron variant, administration officials said Covid vaccines were intended to prevent all symptomatic infections, but they have since abandoned that position.
While Covid vaccines have blunted the spread of earlier variants by up to 70%, “this is clearly not the case with Omicron,” he said. “It would be nice to have something that would do a better job.”
Some experts have said that instead of another round of injections, the best candidate for limiting infections would have been a nasal spray that coats the nose and throat with antibodies to block the virus directly as it enters. But these sprays won’t be available in the United States for at least two or three years.
Until Omicron came along, FDA scientists were so excited about mRNA vaccines that they didn’t consider other boosters, Dr. Marks added: “We may have been temporarily blinded by light.
Still, minimizing the number of infections as much as possible is “obviously a very, very important secondary goal,” said Dr. Sara Oliver, who represents the CDC on the Covid-19 vaccine task force.
In addition to curbing the spread of the virus and societal disruption, reducing infections should reduce cases of long Covid, the constellation of symptoms that can linger for months, she said.
The new plan could rekindle some long-standing tensions. Disagreements over who should recommend vaccines and for whom have agitated these agencies for months.
Typically, FDA scientific advisors review the safety and effectiveness of vaccines and recommend clearance or approval. Experts advising the CDC then issue guidelines on who should receive vaccines and when.
During the pandemic, the lines between the White House, the FDA, and the CDC have often been blurred. “Right now, one of the challenges is that we have a lot of voices talking about vaccination policy, and historically we’ve only had one voice,” Dr Daley said.
When the FDA authorized a second booster, for example, it only did so for adults 50 and older — a distinction that would normally have come from CDC vaccine advisers.
The CDC also made a subtle distinction that has been lost on many Americans: It recommended that adults over 50 could get a booster if they wanted to, not that they should. But the new White House Covid czar, Dr Ashish Jha, has approved the second booster shots.
“It’s not entirely clear that the White House is in a position to make recommendations on vaccines per se, but nonetheless, he said he recommended it,” said Dr. Camille Kotton, physician infectious disease specialist at Massachusetts General Hospital and scientific advisor to the CDC, said of Dr. Jha.
It is unclear who would pay for a vaccination campaign in the fall. The deadlock in Congress over Covid-19 funding jeopardizes the government’s ability to purchase and deliver vaccines to the people who need them most.
“Without urgent additional funding, we are unable to get enough boosters for every American who wants one if they need one in the fall, and we are unable to get newer vaccines. and more effective ones that protect against new variants,” Sarah Lovenheim, assistant secretary for public affairs at the Department of Health and Human Services, said.