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The Virus Variant Spreading in Britain May Make Vaccines Less Effective, Study Shows - The New York Times

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A fast-spreading coronavirus variant first observed in Britain has gained a worrisome mutation that could make it harder to control with vaccines, Public Health England reported on Monday. And on Tuesday, a team of researchers reported an experiment suggesting that this mutation might make vaccines somewhat less effective against the variant.

The variant, known as B.1.1.7, first came to light in December. Researchers determined that it had rapidly become more common across Britain in just a couple of months.

Its spread appears to occur because of its improved ability to infect people. Experiments in test tubes suggest that some of its mutations allow the B.1.1.7 variant to hold on to cells more tightly than other coronaviruses.

Since B.1.1.7’s discovery in Britain, the variant has been reported in 72 other countries. The United States confirmed its first case of the B.1.1.7 variant on Dec. 29, but is conducting little of the genomic sequencing necessary to track the spread of new variants that have caused concern. Since then, the Centers for Disease Control and Prevention has recorded 467 samples of the variant in 32 states. Officials in New York City said on Tuesday that they had identified 13 cases of the variant and were ramping up testing capacity to detect more.

In its latest analysis, Public Health England estimated that the variant’s rate of infection is 25 percent to 40 percent higher than that of other forms of the coronavirus. Some preliminary evidence suggests that it may also cause more deaths.

Several lines of evidence suggest that vaccines will work against the B.1.1.7 variant. On Thursday, the vaccine maker Novavax announced that its British trial found no evidence that B.1.1.7 could evade the vaccine’s defenses.

But in South Africa, where a variant called B.1.351 has surged to dominance, the Novavax and Johnson & Johnson vaccines have both been less effective in trials.

That variant has been reported in 31 countries so far. In the United States, it has turned up in Maryland and in South Carolina.

Scientists suspect that the B.1.351 variant’s partial escape from vaccines is largely thanks to a single mutation, called E484K. Experiments indicate that the E484K mutation makes it harder for antibodies to grab onto the virus and prevent it from entering cells.

Now it turns out that some B.1.1.7 coronaviruses in Britain also have the E484K mutation.

To search for new mutations, British researchers reviewed the 214,159 genomes of coronaviruses that the United Kingdom has sequenced as of Jan. 26. In its report, Public Health England said that they found 11 samples of the B.1.1.7 variant that also had the E484K mutation.

Since that analysis, more of these viruses have come to light. NextStrain, a website where scientists gather and analyze coronavirus genomes, now identifies 16 B.1.1.7 variants that carry the E484K mutation.

These B.1.1.7 coronaviruses gained the mutation thanks to random copying errors as they multiplied inside of people. The evolutionary tree of the coronaviruses suggests that 15 of the variants descend from one common ancestor that gained the E484K mutation. Meanwhile the sixteenth variant seems to have gained the same mutation on its own.

Commenting on Monday’s report, Kristian Andersen, a virologist at Scripps Research Institute in La Jolla, Calif., said that it was impossible yet to say whether the E484K mutation would make these coronaviruses not only more contagious but more resistant to vaccines. “It’s much too early to speculate whether it will, so we’ll have to wait for data,” he said.

Just because the E484K mutation helps the B.1351 variant, the one initially found in South Africa, evade antibodies doesn’t mean it will do the same in other variants. That’s because mutations don’t have a fixed effect. The impact of a single new mutation to a virus depends on the other mutations that the variant already carries.

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Answers to Your Vaccine Questions

Currently more than 150 million people — almost half the population — are eligible to be vaccinated. But each state makes the final decision about who goes first. The nation’s 21 million health care workers and three million residents of long-term care facilities were the first to qualify. In mid-January, federal officials urged all states to open up eligibility to everyone 65 and older and to adults of any age with medical conditions that put them at high risk of becoming seriously ill or dying from Covid-19. Adults in the general population are at the back of the line. If federal and state health officials can clear up bottlenecks in vaccine distribution, everyone 16 and older will become eligible as early as this spring or early summer. The vaccine hasn’t been approved in children, although studies are underway. It may be months before a vaccine is available for anyone under the age of 16. Go to your state health website for up-to-date information on vaccination policies in your area

You should not have to pay anything out of pocket to get the vaccine, although you will be asked for insurance information. If you don’t have insurance, you should still be given the vaccine at no charge. Congress passed legislation this spring that bars insurers from applying any cost sharing, such as a co-payment or deductible. It layered on additional protections barring pharmacies, doctors and hospitals from billing patients, including those who are uninsured. Even so, health experts do worry that patients might stumble into loopholes that leave them vulnerable to surprise bills. This could happen to those who are charged a doctor visit fee along with their vaccine, or Americans who have certain types of health coverage that do not fall under the new rules. If you get your vaccine from a doctor’s office or urgent care clinic, talk to them about potential hidden charges. To be sure you won’t get a surprise bill, the best bet is to get your vaccine at a health department vaccination site or a local pharmacy once the shots become more widely available.

Probably not. The answer depends on a number of factors, including the supply in your area at the time you’re vaccinated. Check your state health department website for more information about the vaccines available in your state. The Pfizer and Moderna vaccines are the only two vaccines currently approved, although a third vaccine from Johnson & Johnson is on the way.

That is to be determined. It’s possible that Covid-19 vaccinations will become an annual event, just like the flu shot. Or it may be that the benefits of the vaccine last longer than a year. We have to wait to see how durable the protection from the vaccines is. To determine this, researchers are going to be tracking vaccinated people to look for “breakthrough cases” — those people who get sick with Covid-19 despite vaccination. That is a sign of weakening protection and will give researchers clues about how long the vaccine lasts. They will also be monitoring levels of antibodies and T cells in the blood of vaccinated people to determine whether and when a booster shot might be needed. It’s conceivable that people may need boosters every few months, once a year or only every few years. It’s just a matter of waiting for the data.

Employers do have the right to compel their workers to be vaccinated once a vaccine is formally approved. Many hospital systems, for example, require annual flu shots. But employees can seek exemptions based on medical reasons or religious beliefs. In such cases, employers are supposed to provide a “reasonable accommodation” — with a coronavirus vaccine, for example, a worker might be allowed to work if they wear a mask, or to work from home.

If you have other questions about the coronavirus vaccine, please read our full F.A.Q.

But in a report posted online Tuesday, Rajiv Gupta, a virologist at the University of Cambridge, and his colleagues reported an experiment they ran to address exactly this question. They combined the E484K mutation with other key mutations found in the B.1.1.7 variant, the one initially found in Britain. The addition of the E484K mutation made it difficult for antibodies to block the viruses. The researchers wrote that they “observed a significant loss of neutralizing activity.”

However, Dr. Gupta and his colleagues used antibodies taken from people who had received just the first of two doses of the Pfizer-BioNTech vaccine. It remains to be seen whether the B.1.1.7 variant with the new mutation, E484K, can evade antibodies after a full vaccination.

Nicholas Davies, a mathematical biologist at the London School of Hygiene and Tropical Medicine, cautioned that with so few of these new coronaviruses, it’s hard to say whether they will become more common than ordinary B.1.1.7 variant.

But it is striking that the same mutation, E484K, has now been documented arising several times in Britain, as well as in South Africa. Meanwhile, in Brazil, yet another variant has also gained the same E484K mutation on its own.

Dr. Davies speculated that the mutation may give the virus an advantage when it is spreading in populations where a lot of people have already been sick with Covid-19. It may be able to evade their antibodies to other variants. “E484K may well convey a fitness advantage in settings where there is existing immunity,” Dr. Davies said.

If so, the virus may be providing the world with a dangerous new example of a common theme in evolution. A good solution can arise more than once — such as flight, which evolved in birds, bats, and insects. Evolutionary biologists call this repeated pattern convergence.

“It’s not great to see this mutation in the B.1.1.7 lineage, although I think it’s no surprise at all,” said Dr. Andersen. “We should expect that to happen.”

Dr. Gupta argued on Twitter that the best defense against this convergence is vaccination. By making it harder for coronaviruses to get from person to person, they will have fewer chances to gain the E484K mutation or other dangerous changes.

“We need to continue vaccinating and drive down transmission,” Dr. Gupta wrote.

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