The Pfizer-BioNTech coronavirus vaccine is 90 percent effective at preventing hospitalization for up to six months, with no signs of waning during that time period, according to a large new U.S. study conducted by researchers at Pfizer and Kaiser Permanente.
The vaccine also provides powerful protection against the highly contagious Delta variant, the scientists found. In a subset of people who had samples of their virus sequenced, the vaccine was 93 percent effective against hospitalization from Delta, compared with 95 percent against hospitalization from other variants.
“Protection against hospitalization remains high over time, even when Delta predominates,” said Sara Tartof, an epidemiologist at Kaiser Permanente Southern California and the first author of the study.
The vaccine’s effectiveness against infection did decline over time, however, falling from 88 percent during the first month after vaccination to 47 percent after five months.
The findings, published in The Lancet on Monday, come amid a debate over whether, and when, booster shots may be necessary. The Food and Drug Administration has authorized boosters for recipients of the Pfizer vaccine who are 65 or older or at high risk for infection or severe disease. And the Biden administration has pushed for boosters to be made more widely available to the general population.
But many scientists and public health experts have pushed back, arguing that the nation’s priority should be getting the shots to people who have not yet been vaccinated and that the vaccines still appear to provide good protection against the worst outcomes, including severe disease and death.
Data from Israel indicates that the Pfizer vaccine’s effectiveness against infection dropped to 39 percent in late June and early July, down from 95 percent in January through early April. But it remained more than 90 percent effective against severe disease during that time period.
On the other hand, a recent study from the Centers for Disease Control and Prevention reported that the vaccine’s effectiveness against hospitalization dropped to 77 percent after four months, compared to 91 percent in the first few months.
In the new study, the researchers analyzed the electronic health records from more than 3.4 million members of Kaiser Permanente Southern California, between Dec. 14, 2020, and Aug. 8, 2021.
Overall, the vaccine was 90 percent effective against hospitalization and 73 percent effective against infection. Among those who were 65 or older, it was 86 percent effective against hospitalization and 61 percent effective against infection.
The researchers sequenced more than 5,000 samples of the virus. Overall, the Delta variant made up 28 percent of these samples, though it was the dominant variant in June and July.
The vaccine was slightly less effective against Delta than the other variants, providing 75 percent protection against infection with Delta, compared to 91 percent protection against the other variants.
But protection against infection declined at a similar rate over time, the researchers found. After four months, the effectiveness against infection had dropped to 53 percent against Delta and 67 percent against the other variants.
The findings could give fuel to both sides of the booster debate, Dr. Tartof said.
“The question is what do you want your booster program to do?” she said. Some may say this data supports boosters because it shows an increase in breakthrough infections over time, she said. Others, though, could point to the vaccine’s steady protection against severe disease and argue that boosters aren’t necessary.
Johnson & Johnson is planning to ask U.S. regulators early this week to authorize a booster shot of its coronavirus vaccine, according to officials familiar with the company’s plans. The firm is the last of the three federally authorized vaccine providers to call for extra injections, amid mounting evidence that at least older adults and others in high-risk groups need more protection.
Federal officials have become increasingly worried that the more than 15 million Americans who received the Johnson & Johnson vaccine face too much risk of severe Covid-19. The Food and Drug Administration on Friday scheduled an Oct. 15 meeting of its expert advisory committee to discuss whether to grant emergency use authorization of a booster shot of the vaccine.
That is part of a broader effort by the government to shore up the protection provided by all three vaccines. Regulators last month authorized a booster shot for many recipients of Pfizer-BioNTech’s vaccine and are contemplating doing the same this month for recipients of Moderna’s.
The fact that the advisory committee meeting on Johnson & Johnson was scheduled even before the company filed an application to the Food and Drug Administration reflects a particular sense of urgency in the Biden administration to provide more protection to recipients of that vaccine.
Although the federal government has emphasized for months that all three vaccines are highly effective, a recent study by the Centers for Disease Control and Prevention found that Johnson & Johnson’s single-dose vaccine was only 71 percent effective against hospitalization from Covid, compared with 88 percent for Pfizer-BioNTech’s vaccine and 93 percent for Moderna’s.
“Real-world data suggest that the two-dose Moderna and Pfizer-BioNTech mRNA vaccine regimens provide more protection” than the single dose of Johnson & Johnson, the researchers said. Other research found that Johnson & Johnson recipients were more likely to have breakthrough infections or symptomatic Covid than recipients of the other two vaccines.
Johnson & Johnson cites some studies with better results: A study of nearly two million people, funded by the company, estimated that the vaccine was 81 percent effective against hospitalization. Other research suggests that protection from Johnson & Johnson’s vaccine does not wane over time like protection from Pfizer-BioNTech’s vaccine.
Nonetheless, Johnson & Johnson now appears to agree with federal officials that a single shot of its vaccine is not enough.
Last month, the company announced that a second dose, given two months after the first, increased the vaccine’s effectiveness against symptomatic Covid by about 22 percentage points, to 94 percent. Johnson & Johnson also said two shots were 100 percent effective against severe disease, although that estimate was less conclusive.
Northwell Health, New York State’s largest health care provider, announced on Monday that 1,400 employees — less than 2 percent of its staff — refused to get vaccinated against the coronavirus and had to leave their jobs.
New York is requiring that the state’s more than 650,000 hospital and nursing home workers be vaccinated, a mandate that started to take effect last week, prompting tens of thousands of employees to get their shots. Others filed lawsuits, and courtrooms across the state are determining when and how to allow exemptions to the requirement.
New York’s health care mandate is particularly strict: Employees do not have the option for weekly testing or exemptions for religious reasons, though the latter is being challenged in the courts.
The Biden administration has made a vaccine requirement for many health care workers a central part of its effort to vaccinate the country, and many medical workers, particularly those at large hospital systems like Northwell, appear to be complying with vaccine mandates.
In New York state, 87 percent of hospital workers were completely inoculated as of Sept. 29, according to state health data.
The possibility of widespread staff shortages loomed before the mandate took effect, so much so that Gov. Kathy C. Hochul declared a state of emergency last week that would allow her to deploy National Guard troops, expedite visas for workers from abroad and recruit newly graduated or recently retired health care professionals to fill staffing shortages.
So far the number of workers in New York who have left their jobs is relatively small, and does not appear likely to result in the kind of staff shortages that could compromise patient care. Still, the governor’s contingency plans reflect the fears that New York hospitals could be imperiled in the same way that hospitals were in parts of the country that the Delta variant has devastated.
Northwell, which employs more than 76,000 people said in a statement that vaccinating all of its employees would allow the provider to “provide exceptional care at all of our hospitals, without interruption and enable all our facilities to remain open and fully operational.”
“Northwell has taken a rapid, aggressive approach to move successfully toward full vaccination compliance while maintaining continuity of care and ensuring that our high standard of patient safety is not compromised in any way,” the statement continued.
Some Northwell workers protested the vaccine mandates when they were first announced in August.
John Trinchino, a registered nurse, said he was fired last week from his job at Staten Island University Hospital, a Northwell facility. Mr. Trinchino said that he had Covid-19 earlier in the pandemic, and that he thought the antibodies from his infection would protect against further illness.
Mr. Trinchino added that requiring vaccination violated his civil liberties, and he did not plan on getting vaccinated.
“All this is going to lead to is worse care for the patients, and I’m just disgusted by it,” he said.
Joe Kemp, a spokesman for Northwell, said the company regretted losing any workers over vaccinations. He said a few thousand employees had gotten vaccinated as the deadline neared, and that some who initially lost their jobs had gotten shots and returned to work.
Terminated workers have the opportunity to interview for reinstatement for 30 days, Mr. Kemp said, but Northwell was “openly recruiting” for the newly vacant jobs.
“The goal was to get people vaccinated, not to get people terminated,” he said.
Kimiko de Freytas-Tamura contributed reporting.
Louisiana’s largest nonprofit health care provider is increasing its insurance fees next year for employees whose spouses or domestic partners are not vaccinated against Covid.
In a letter to its employees last month, the provider, Ochsner Health, said that it was adding the extra charge — about $200 a month — for unvaccinated spouses and domestic partners who covered by the company’s insurance plan.
The letter said the move was an effort to “protect our entire Ochsner team, which includes employees, their families and the communities we serve.”
Warner Thomas, the company’s president and chief executive, said in a statement that spouses and domestic partners would be allowed to file for medical or religious exemptions to the policy.
“This is not a mandate,” he said, noting that the spouses and domestic partners could switch insurance plans to avoid the new fee.
“The reality is the cost of treating Covid-19, particularly for patients requiring intensive inpatient care, is expensive,” he added.
Mr. Thomas said that about 90 percent of the company’s Covid patients since December had been unvaccinated. According to a New York Times analysis in August, fully vaccinated people accounted for just 1 percent of Covid hospitalizations in Louisiana. The analysis looked at 40 states and the District of Columbia, and the rate in most of them was under 2 percent.
In August, Ochsner said that its employees must be vaccinated by the end of this month. Around 70 percent of its employees were inoculated at the time the mandate was announced.
The provider’s decision to charge extra was similar to a policy implemented by Delta Air Lines, which said in August that starting on Nov. 1, it would charge any employee who remains unvaccinated an additional $200 per month to remain on the company’s health care plan.
Delta became the first large U.S. employer to embrace an idea that has been widely discussed but is mired in legal uncertainty: charging unvaccinated employees more for health insurance.
Insurance surcharges may appeal to companies that are seeking a less coercive means to increase vaccination rates, said Wade Symons, a partner at Mercer, a benefits consulting firm.
New infections in Louisiana on Sunday were less than a fifth of the amount in August, when the state reached a pandemic high, according to a New York Times database. Hospitalizations are experiencing a similar trend.
The state authorities are still struggling to vaccinate people, however. Less than half of the state’s eligible population is fully vaccinated, according to a Times database, which is below the nationwide average of 56 percent.
Mayor Brandon M. Scott of Baltimore tested positive for Covid-19 on Monday despite being vaccinated, his office said.
Mr. Scott, 37, was asymptomatic and self-isolating at his home in the city, Cal Harris, a spokesman for the mayor, said in a statement on Monday afternoon.
“This could have been a different situation if Mayor Scott were not vaccinated,” Mr. Harris said.
Mr. Harris added that city health officials were doing contact tracing on the colleagues that Mr. Scott interacted with at outdoor events last weekend.
A spokeswoman for the mayor said he attended two events on Saturday: the opening of a neighborhood center and a groundbreaking ceremony for a development company. On Sunday, he made an appearance at the city’s Parade of Latino Nations.
Zeke Cohen, a member of the Baltimore City Council, said on Twitter on Monday that he was with the mayor at the parade, but he later tested negative for the virus.
The mayor’s positive result came as Baltimore grapples with a significant rise in new infections. On Sunday, according to a New York Times database, the average number of daily new cases over the last seven days was 122.
During a plateau at the beginning of July, the daily average was 5 new cases per day. Slightly less than two-thirds of the city’s residents who are eligible for vaccinations are fully inoculated, according to a Times database.
Mr. Scott has been trying to improve the city’s vaccination rate. He said last month that all city workers must be inoculated by Oct. 18.
A second dose of the coronavirus vaccines made by Pfizer-BioNTech and Moderna can nearly triple the chances of a rare heart condition in young men, according to a large new study published on Monday. But the absolute risk of the condition, called myocarditis, remains extremely low.
The study found 5.8 cases per million second doses in men, with an average age of 25 years. The risk after the first dose was much less, at 0.8 cases per million, not more than normally would be seen in that age group. The findings were published in the journal JAMA Internal Medicine.
The results may be underestimates. The researchers tracked the medical status of vaccinated individuals for only a short time, and may have missed people whose heart problems were not severe enough to require hospitalization.
Concerns about myocarditis, an inflammation of the heart muscle, have been the subject of intense discussion among advisers to the Centers for Disease Control and Prevention, and may have led the Food and Drug Administration to ask vaccine manufacturers to expand their clinical trials in younger children.
Experts have thus far said that the benefits of the vaccines far outweigh the rare risk of myocarditis. But citing the heart condition as a worry, regulators in some countries like Britain and Hong Kong have recommended a single dose of the vaccine for adolescents aged 12 to 15 years.
Other studies have also found that vaccination increases the risk of myocarditis. An Israeli study published in August looked at the electronic health records of about 2 million people and found an additional 2.7 cases of myocarditis for every 100,000 vaccinated people, compared with unvaccinated ones.
But the same research found that the risk of myocarditis from having Covid-19 was much higher, resulting in an extra 11 cases of the condition for every 100,000 infected people.
The C.D.C. has estimated that for every million vaccinated boys ages 12 to 17, the shots might cause a maximum of 70 myocarditis cases, but would prevent 5,700 infections, 215 hospitalizations and two deaths.
In the new study, researchers analyzed the medical records of 2.4 million members of the Kaiser Permanente Southern California health care system, aged 18 years or older. The participants had received at least one dose of the Pfizer-BioNTech or Moderna vaccines between Dec. 14, 2020, and July 20, 2021.
The team identified individuals who were hospitalized within 10 days of receiving a vaccine dose and discharged with a diagnosis of myocarditis. The researchers found 15 cases of confirmed myocarditis in the vaccinated group, 13 of which were observed after the second dose.
None of those affected had a history of heart problems, and none were readmitted to the hospital after being discharged.
LONDON — Streamlined coronavirus restrictions on international travel in and out of England came into effect on Monday, including an easing of testing and quarantine requirements for fully vaccinated arrivals.
The change, which went into effect at 4 a.m. local time, replaced a three-tier traffic light-inspired system with a single “red” list of countries and territories that present the highest risk.
Critics had complained that the old system — which periodically involved the government altering the risk status of countries and which left Britons scrambling to figure out the latest rules during vacations — had caused confusion within the travel industry.
“We are accelerating towards a future where travel continues to reopen safely and remains open for good,” Grant Shapps, Britain’s transportation secretary, said in a statement, “and today’s rule changes are good news for families, businesses and the travel sector.” Mr. Shapps attributed the move to the vaccination rate; 67 percent of the population of the United Kingdom is fully vaccinated.
Under the new rules, fully vaccinated travelers entering England will no longer be required to take a pre-departure coronavirus test when returning from a country that is not on the red list. And though travelers must still pay for a test to take on the second day after their return, beginning later this month, the government said it would accept less expensive rapid tests over polymerase chain reaction, or P.C.R., tests.
Arrivals who tested positive, however, would still need to isolate and take a P.C.R. test, “which would be genomically sequenced to help identify new variants,” the government said.
Testing and quarantine requirements for those who are not fully vaccinated remain the same, as do rules for those entering from “red” list countries.
After the success of a pilot test involving arrivals from United States and Europe, England will also begin a phased approach to recognizing vaccinations that have been administered in other countries and territories, expanding that list on Monday to over 50 countries including the United Arab Emirates, Japan and Canada.
In the past week, Britain reported an average of 33,779 daily cases and 112 daily deaths, according to a New York Times database. Cases have increased by 16 percent from the average two weeks ago.
The European Medicines Agency, the European Union’s main drug regulator, said on Monday that a booster shot of the Pfizer-BioNTech coronavirus vaccine could be given to healthy adults at least six months after the second dose.
The agency said data showed that antibody levels increased in people age 18 to 55 with normal immune systems who had received a third dose of the vaccine. It is still assessing booster shots of the Moderna vaccine.
The agency also said that people with “severely weakened” immune systems could receive an extra dose of the Pfizer-BioNTech or Moderna vaccines as early as 28 days after a second dose. It is expected that an additional shot “would increase protection in at least some of the patients,” the agency said.
The recommendation is based on studies showing that an extra dose of those vaccines could increase the ability to produce antibodies in organ transplant recipients.
In the European Union, vaccination campaigns are a prerogative of national governments, and each of the 27 member nations can decide whether to give booster shots to all of their adult residents. Some E.U. nations, such as France, Germany and Belgium, started giving extra doses to older people and those with weakened immune systems last month, while the Czech Republic and Hungary opened this possibility to all adults.
Although the European Union has one of the highest vaccination rates in the world, with over 73 percent of adults fully inoculated, there is no coronavirus vaccine authorized yet for children. The European Center for Disease Prevention and Control warned last week that the average level of vaccination across the bloc is not sufficient to halt the virus from spreading if governments relax Covid-19 restrictions.
The agency said it was carefully monitoring “very rare” side effects of a booster shot, such as inflammatory heart conditions, but that for the moment the risk was not known.
The decisions of wealthier nations to administer booster shots while the rest of the world remains largely unvaccinated have raised alarm among health experts. Dr. Tedros Adhanom Ghebreyesus, the director general of the World Health Organization, has called for a moratorium on coronavirus vaccine booster shots for people who are not immunocompromised until at least the end of the year.
A deep sense of anxiety has crept through Britain as supply shortages afflict the nation — and threaten disruptions to the Christmas dinner table.
Slaughterhouses are understaffed and are processing a smaller-than-usual number of pigs. There is a shortage of drivers to move pork to grocery stores and butcher shops. And there are fewer butchers to prepare the meat for consumers.
If the problems persist, farmers like Simon Watchorn, who raises pigs about two hours northeast of London, may have to start culling. Pigs grow about 15 pounds each week, and after a certain point, they are too big for slaughterhouses to process.
Mr. Watchorn, 66, is one of many producers of food and other goods warning of a daunting winter ahead for Britons. Shortages continued to bedevil the British economy on Monday as gas stations in London and in southeastern England reported trouble getting fuel, and the government began deploying military personnel to help ease the lack of drivers. Supermarket consortiums say that pressures from rising transport costs, labor shortages and commodity costs are already pushing prices higher and will likely continue to do so.