As winter looms and Americans increasingly gather indoors without masks or social isolation, a rise in cases and hospitalizations in counties across the nation is being caused by a mixture of new coronaviruses.

The Biden administration's plan for preventing a national surge depends on persuading Americans to get updated booster shots. Scientists are questioning the strategy.

John Moore said that older adults, immunocompromised people and pregnant women should get the booster shots.

The picture is not as clear for Americans who are younger. Most of them have built immunity through multiple vaccine doses and are not at risk of dying from Covid.

The newer variant, called BQ.1 and BQ.1.1, are spreading quickly, and boosters don't seem to do much to prevent infections with them.

If you are at medical risk, you should get boosted and if you are at psychological risk, you should get boosted. Don't believe that it will give you some kind of amazing protection against infections, and then you'll just party like there's no tomorrow.

Both the original version of the corona virus and the Omicron variant have been targeted by the most recent boosters. Only a small percentage of adults have taken the latest shot.

Dr. Marks acknowledged the limitations of the available data on the updated boosters in an interview.

He said that they were not sure how well the vaccines would work against disease.

Even modest improvements in vaccine response could have important positive consequences for public health. I think the answer is that we should encourage people to get that booster since the downside is low.

  • Shifting Attitudes: Most offices, restaurants and schools are back to business as usual, but the coronavirus has not gone away.
  • Long Covid: People who took the antiviral drug Paxlovid within a few days after being infected with the coronavirus were less likely to experience long Covid months later, a study found.
  • Updated Boosters: New findings show that updated boosters by Pfizer and Moderna are better than their predecessors at increasing antibody levels against the most common version of the virus now circulating.
  • Personality Changes: New research suggests that Covid's disruption of social rituals and rites of passage have made people less extroverted, creative, agreeable and conscientious.

The Pfizer-bioNTech and Moderna vaccines need to be changed for a new approach to protect Americans. It would be ideal for a universal vaccine to target parts of the coronaviruses that don't change. An injected vaccine may be more effective at preventing infections than a nasal vaccine.

It's not a sustainable strategy to chase variant by variant in the vaccine. There is a need for better vaccine designs but a change of attitude at the government level.

ImagePresident Biden fiddles with his shirt cuffs after receiving a shot. The nurse who administered the shot stands behind him in a dark blue suit and mask and screens behind the president can read in part, “Vaccines.”
President Biden recuffed himself after receiving the bivalent booster shot last month to promote its rollout. Booster shots are the mainstay of the administration’s Covid strategy.Credit...Doug Mills/The New York Times
President Biden fiddles with his shirt cuffs after receiving a shot. The nurse who administered the shot stands behind him in a dark blue suit and mask and screens behind the president can read in part, “Vaccines.”

Pfizer- BioNTech and Moderna reported that their bivalent shots yielded higher levels of antibodies than the original vaccine.

The companies were not measuring against the fast-growing BQ.1 and BQ. 1.1 variant. Preliminary research shows that the updated boosters are only marginally better than the original vaccines at protecting against newer versions.

The studies are small and have not yet been published in a journal. Results from many teams agree.

It is not likely that any of the vaccines or boosters will provide substantial and sustained protection against acquisition of an infectious disease.

It's difficult to design a vaccine for a changing virus. To make enough vaccine for the fall, Pfizer, Moderna and federal regulators had to pick which coronaviruses to target.

BA.4 is almost completely gone. Less than 30 percent of cases have BA.5 as the main component. The number of people in Europe have gone up. It now accounts for 44 percent of infections in the United States.

BQ. 1.1 is seven times more resistant to the body's immune defenses than the original coronaviruses. He said that it has the most striking immune escape. BQ.1 is expected to act the same way.

The variant that best evades the body's immune response is likely to outrun its rivals because most Americans have some degree of immunity to the coronaviruses.

Any booster would increase their levels.

ImageA close-up view of a row of light blue vials on a circular assembly line.
The updated vaccine on the assembly line at a Pfizer production facility in Kalamazoo, Mich. Some experts say a variant-specific booster may have had better chances of success on its own than when combined with the original vaccine.Credit...Pfizer, via Associated Press
A close-up view of a row of light blue vials on a circular assembly line.

The fact that the dose is bivalent doesn't mean a lot. A study done in Australia suggested that a variant-specific shot was unlikely to be more effective than the original vaccine.

The World Health Organization warned last month that the majority of the benefit is from the provision of a booster dose.

Most of the antibodies elicited by a vaccine targeting BA.5 still recognize the original viruses, according to studies.

Immune imprinting is a phenomenon in which the body preferentially repeats its immune response to the first variant it encounters. The majority of the antibodies people make are for the original coronaviruses.

It is easier for the immune system to return to something it has already seen. Dr. Krammer has worked for Pfizer.

He and other experts think that the booster shots should have beenvalent. The shot's effectiveness was undermined by the manufacturers halving the Omicron-specific component of the new booster.

Despite recent research, Dr. Krammer was still more positive about the boosters. He said that the new studies looked at the immune response immediately after the vaccine.

He thinks it is not worse if there is a good or significant benefit. You might as well get the benefit if you get the vaccine.

A second dose of a bivalent vaccine that builds on the immune response after the first could be a way to circumvent immune imprinting.

Dr. Marks said, "What we need to do now to get us through the next few months when I think we are in another wave of Covid." We need to lean into how we're going to do things differently in the future.

ImageA woman in a surgical mask holds up the sleeve of her gray Mickey Mouse T-shirt to reveal a bandage where she received a booster shot.
A woman under observation after receiving the bivalent booster vaccine in Phoenix.Credit...Ash Ponders for The New York Times
A woman in a surgical mask holds up the sleeve of her gray Mickey Mouse T-shirt to reveal a bandage where she received a booster shot.

The F.D.A. gave the go-ahead for the boosters to be used for at least two months. It may backfire if you boost again so soon. The longer the interval between boosts, the more time the immune system has to respond.

Adding another shot to the regimen doesn't seem to motivate Americans to get the vaccine.

"We are already close to the floor because each new booster we roll out is going to have a lower and lower take up."

The lifting of other precautions may force the Biden administration to promote boosters. She said that most people make decisions based on what others in their social network do or what their community leaders recommend.

The benefits are limited, so we shouldn't spend a lot of political capital trying to get people to get it. Getting people like me to get their fifth shot is more important than getting people like me to get the initial vaccine series.

If other vaccines, such as Novavax or J.&J., were available for that purpose, the Biden administration might have a better chance of persuading people to get boosters. People who have had a strong reaction to the vaccine may be hesitant to get a booster.

Even from a scientific point of view, it may be better to use different vaccines instead of using the same ones.

After reviewing the data, the F.D.A. could recommend Novavax as a second booster. Until then, that vaccine can only be used as a first booster for people who can't get a vaccine.

Dr. Moore thinks that rule is ridiculous. Why is the F.D.A. putting restrictions like this if its goal is to increase vaccine take in the American population?