People who are infected with the highly contagious Delta variant are twice as likely to be hospitalized as those who are infected with the Alpha variant, according to a large new British study.
The study, published in The Lancet Infectious Diseases journal on Friday, is an analysis of more than 40,000 coronavirus infections in England. It adds to evidence suggesting that Delta may cause more severe illness than other variants do.
Fewer than 2 percent of the infections occurred in fully vaccinated people, and there was not enough data to draw firm conclusions about hospitalization risks in that group specifically, the researchers said.
“The main takeaway is that if you have an unvaccinated or only partially vaccinated population, then an outbreak of Delta can lead to a higher burden on hospitals, on health care, than an Alpha outbreak would,” said Anne Presanis, a senior statistician at the University of Cambridge and one of the study’s lead authors.
The Delta variant, which was first detected in India, is roughly twice as infectious as the original virus and as much as 60 percent more transmissible than the Alpha variant, which was first identified in Britain.
In the new study, researchers analyzed the health data of people who tested positive for the virus in England from March 29 to May 23, as Delta was spreading through the country. Seventy-four percent of people were unvaccinated, 24.2 percent were partly vaccinated, and 1.8 percent were fully vaccinated.
Genetic sequencing confirmed that 80 percent of the study participants had been infected with the Alpha variant, while 20 percent had been infected with Delta.
For both groups, the risk of hospitalization was small, the researchers found. Just 2.2 percent of people with Alpha and 2.3 percent of those with Delta were admitted to the hospital within two weeks of testing positive for the virus.
But people infected with the Delta variant were younger, on average. When the researchers adjusted for age and other factors that are known to affect disease severity, they found that when Delta caused the infection, the overall risk of being hospitalized was more than two times as high.
When the researchers broke down the data by vaccination status, they confirmed that Delta doubled the risk of hospitalization for those who were unvaccinated or had received their first dose less than three weeks earlier. The fully vaccinated group was too small to be rigorously analyzed on its own, the researchers said.
“We already know that vaccination offers excellent protection against Delta, and as this variant accounts for over 98 percent of Covid-19 cases in the U.K., it is vital that those who have not received two doses of vaccine do so as soon as possible,” Dr. Gavin Dabrera, a lead author of the paper and an epidemiologist at Public Health England, said in a statement.
In Louisiana, where daily deaths from Covid reached their highest levels this week, stretched hospitals are having to modify the intense preparations they would normally make ahead of an expected strike from Hurricane Ida.
Louisiana’s medical director, Dr. Joseph Kanter, asked residents on Friday to avoid unnecessary emergency room visits to preserve the state’s hospital capacity, which has been vastly diminished by its most severe Covid surge of the pandemic.
And while plans exist to transfer patients away from coastal areas to inland hospitals ahead of a hurricane, this time “evacuations are just not possible,” Gov. John Bel Edwards said at a news conference.
“The hospitals don’t have room,” he said. “We don’t have any place to bring those patients — not in state, not out of state.”
The governor said officials had asked hospitals to check generators and stockpile more water, oxygen and personal protective supplies than usual for a storm. The implications of a strike from a Category 4 hurricane while hospitals were full were “beyond what our normal plans are,” he added.
Mr. Edwards said he had told President Biden and Deanne Criswell, the administrator of the Federal Emergency Management Agency, to expect Covid-related emergency requests, including oxygen.
The state’s recent wave of Covid hospitalizations has exceeded its previous three peaks, and staffing shortages have necessitated support from federal and military medical teams. On Friday, 2,684 Covid patients were hospitalized in the state. This week Louisiana reported its highest ever single-day death toll from Covid — 139 people.
Oschner Health, one of the largest local medical systems, informed the state that it had limited capacity to accept storm-related transfers, especially from nursing homes, the group’s chief executive, Warner L. Thomas, said. Many of Oschner’s hospitals, which were caring for 836 Covid patients on Friday, had invested in backup power and water systems to reduce the need to evacuate, he said.
The pandemic also complicated efforts to discharge more patients than usual before the storm hits. For many Covid patients who require oxygen, “going home isn’t really an option,” said Stephanie Manson, chief operating officer of Our Lady of the Lake Regional Medical Center in Baton Rouge, which had 190 Covid inpatients on Friday, 79 of them in intensive care units.
The governor said he feared that the movement of tens or hundreds of thousands of evacuees in the state could cause it to lose gains made in recent days as the number of new coronavirus cases began to drop. Dr. Kanter urged residents who were on the move to wear masks and observe social distancing. Many of the state’s testing and vaccination sites were slated to close temporarily.
Under pressure from Mayor Bill de Blasio and other city leaders, the United States Tennis Association reversed its lax coronavirus protocols for the upcoming U.S. Open tournament, which opens to thousands of fans on Monday.
Originally, the tournament did not require any proof of vaccination or a recent negative coronavirus test for fans to enter, and there were no mask mandates, either. But the mayor’s office stepped in over the past two days to demand stricter protocols.
On Friday evening, the tournament announced on its Twitter account that proof of at least one vaccine shot would now be required for entrance to the grounds for all fans ages 12 and older. No masks are required.
The mayor’s office was adamant that fans entering Arthur Ashe Stadium, the largest venue on the grounds of the Billie Jean King National Tennis Center, be vaccinated. But the U.S.T.A. took it a step further and made it a requirement for all fans entering the grounds of the tournament.
“Today, the U.S.T.A. was informed that the New York City mayor’s office will be mandating proof of Covid-19 vaccination for entrance to Arthur Ashe Stadium,” the statement said. “Given the continuing evolution of the Delta variant and in keeping with our intention to put the health and safety of our fans first, the U.S.T.A. will extend the mayor’s requirement to all U.S. Open ticket holders 12 years old and older.”
Mr. de Blasio was not the only concerned city official. After the tournament announced on Wednesday that no vaccines or masks would be required, Mark Levine, a City Council member from Manhattan, said he was “alarmed” that the U.S. Open could become a superspreader event, especially with so many visitors from around the world and the country visiting the tournament in Queens, and also touring Manhattan.
Levine was pleased by the reversal.
“I feel enormous relief,” he said, “and it’s just in the nick of time with crowds due to arrive on Monday.”
WASHINGTON — President Biden suggested on Friday that the government could offer coronavirus vaccine booster shots to most vaccinated adults sooner than eight months after a second shot, underscoring the administration’s concerns about the spread of the Delta variant.
Mr. Biden’s comments came during an Oval Office meeting with Prime Minister Naftali Bennett of Israel, whose government has already given booster shots to about a third of its population.
Just nine days earlier, the president announced that his administration would begin offering third shots the week of Sept. 20 to adults who had received their second dose of the Pfizer-BioNTech or Moderna vaccines at least eight months earlier.
But during the meeting with Mr. Bennett, Mr. Biden said his administration was weighing other options as well.
“We were going to start mid-September, but we’re considering the advice you’ve given that we should start earlier,” Mr. Biden said. “The question raised is should it be shorter than eight months? Should it be as little as five months? That’s being discussed.”
The White House press secretary, Jen Psaki, later played down the significance of Mr. Biden’s comments, saying the administration’s original eight-month proposal was unchanged. She said the president would continue to rely on guidance from federal health experts.
The Food and Drug Administration is racing to collect and analyze data from the vaccine manufacturers, the National Institutes of Health and elsewhere on the safety and efficacy of booster shots. Administration officials are meeting daily to discuss how to administer extra shots to vaccinated Americans.
While senior federal health officials appear to uniformly agree that booster shots are necessary, they and Mr. Biden have repeatedly said that they are contingent upon the F.D.A. determining that they are safe and effective, as well as on a recommendation from the Centers for Disease Control and Prevention to offer them. Some outside experts said the White House was pushing a broad plan for booster shots before regulators have had a chance to analyze the data.
American intelligence agencies have not been able to determine if the coronavirus pandemic was the result of an accidental leak from a lab or if it emerged more naturally, according to declassified portions of a report to the White House released on Friday.
The nation’s spy agencies, the Office of the Director of National Intelligence said, are unlikely to reach a conclusion without more cooperation from China or a new source of information.
As debates about the origins of the pandemic intensified, Mr. Biden ordered the nation’s intelligence agencies three months ago to draft a report on the source of the virus.
After the review, the National Intelligence Council and four other intelligence community elements reported that they believed the virus that causes Covid was most likely created by “natural exposure to an infected animal through an animal infected with it, or close progenitor virus.”
Before the review was conducted, only two agencies favored the natural exposure theory. But the new report said the intelligence council and other agencies favoring the natural theory had low confidence in their conclusions — a sign that the intelligence behind the assessment was not strong and that conclusions could change.
On the other side of the debate, one agency, with moderate confidence, said it had concluded that the pandemic was the result of “a laboratory-associated incident.” According to the declassified report, analysts at that agency gave weight to the risky nature of work on coronaviruses. The agency also said the accident most likely involved “experimentation, animal handling, or sampling by the Wuhan Institute of Virology.”
The intelligence agencies all agree that the virus was unlikely to have been created as any kind of biological weapon, the same stance the U.S. government has maintained for more than a year. The agencies also agree that the initial exposures that caused the outbreak occurred “no later than November 2019,” according to the declassified conclusions.
Critical to the debate over the virus origins, American intelligence officials do not believe the Chinese officials knew about it at the time of the outbreak, the report said.
An unvaccinated elementary schoolteacher infected with the highly contagious Delta variant spread the virus to half of the students in a classroom, seeding an outbreak that eventually infected 26 people, according to a new report from the Centers for Disease Control and Prevention.
The unusually detailed study, which comes as school districts across the country reopen, seems certain to intensify the debate over vaccine mandates in schools. A handful of school districts, including New York City, have already announced vaccine requirements for teachers and staff.
The classroom outbreak occurred in Marin County, Calif., in May. Neither the school nor the staff members and students involved were identified.
The teacher first showed symptoms on May 19, but worked for two days before getting tested. During this time, the teacher read aloud, unmasked, to a class of 24 students, despite rules requiring both teachers and students to wear masks indoors.
All the students were too young for vaccination.
On May 23, the teacher reported testing positive for infection with the coronavirus. Over the next several days, 12 of the students also tested positive.
In the classroom, rates of infection roughly corresponded to the seating chart. Everyone in the front row tested positive, tapering to 80 percent in the first two rows.
In the back three rows, only 28 percent of students tested positive. “If teacher has no mask, move to the back of the class,” Edward Traver, an infectious disease fellow at the University of Maryland Medical Center, said in a Twitter message.
Six students in another grade at the school also tested positive for the virus. The cases spread outward from the school into the community: At least eight parents and siblings of the infected students, three of whom were fully vaccinated, also were infected.
State health researchers sequenced specimens of the virus from many of the positive cases and found that all had been infected with the Delta variant.
The outbreak was likely fueled both by Delta’s high level of infectiousness and by the fact that the teacher did not follow recommended safety precautions, the researchers said.
“We have to make sure both schools and individuals are working together to make sure we are safe,” said Tracy Lam-Hine, an epidemiologist at Marin County Health and Human Services and an author on the new report. “It can’t be just one or the other.”
Canadian regulators on Friday authorized the use of Moderna’s Covid-19 vaccine in children 12 and older.
“After a thorough and independent scientific review of the evidence, Health Canada has determined that the vaccine is safe and effective at preventing Covid-19 in youth aged 12 to 17,” the agency wrote in a tweet.
The Moderna vaccine is being used in those 18 and older in the United States, Canada, the European Union and Britain. Moderna has filed for emergency use of its vaccine in the United States for children 12 and older, but the Food and Drug Administration has yet to rule on the request.
Until now, the only vaccine approved for adolescents in North America has been the shot from Pfizer-BioNTech.
Despite a slow start, Canada has moved rapidly to inoculate its population. More than 72 percent of Canadians have received at least one dose of the vaccine, while about 65 percent are fully vaccinated, according to data from Health Canada.
An average of 2,831 cases per day were reported in Canada in the last week, according to a New York Times database. Cases have increased by 74 percent from the average two weeks ago and deaths have increased by 164 percent.
Caleb Wallace, a leader in the anti-mask movement in central Texas, became infected with the coronavirus and has been in an intensive care unit for the past three weeks, barely clinging to life, his wife, Jessica, said.
Mrs. Wallace said her husband’s condition was declining and doctors have run out of treatment options. On Saturday he will be moved to a hospice at Shannon Medical Center in San Angelo, Texas so that his family can say their goodbyes, she said.
Mr. Wallace, 30, has lived in San Angelo for most of his life and works at a company that sells welding equipment. He checked into the Shannon Medical Center on July 30. Mrs. Wallace set up a GoFundMe page that has collected over $27,000, to cover the cost of medical bills.
Earlier that month, Mr. Wallace had organized a “Freedom Rally” for people who were “sick of the government being in control of our lives.”
He founded the San Angelo Freedom Defenders, a group that hosted a rally to end “Covid-19 tyranny” according to a YouTube interview with him.
“They believed the coronavirus was a hoax and they felt that the government was being too heavy-handed when it came to masks,” San Angelo’s mayor, Brenda Gunter, said in an interview.
In April, Mr. Wallace penned a letter to the San Angelo Independent School District demanding they “rescind ALL COVID-related policies immediately,” and questioning the science and efficacy of masks for school children.
Mr. Wallace’s father, Russell Wallace, said his son firmly believes mask and vaccination requirements are a violation of personal liberties. “After watching all the government overreach here he decided he wanted to do something about it,” Russell Wallace said.
Mrs. Wallace, who is pregnant with the couple’s fourth child, told the San Angelo Standard-Times that when her husband first felt ill, he took a mix of vitamin C, zinc, aspirin and ivermectin — a drug typically used to treat parasitic worms in both people and animals that has been touted as coronavirus treatment but was recently proven ineffective against the virus.
She said her husband respected her own decision to wear a mask. “We joked around about how he was on one side and he was on the other, and that’s what made us the perfect couple and we balanced each other out,” she said.
She added that her three children are up-to-date on their vaccines and that she herself planned to get the coronavirus vaccine after her baby is born in late September. “We are not anti-vaxxers,” she said.
Still, Mrs. Wallace said her husband strongly believed the decision to get vaccinated or to wear a mask should rest with an individual and not with the government. “That is one of the few things I agreed with my husband on.”
Mayor Gunter said Mr. Wallace had an overwhelming love for his city. During the state’s record-breaking winter storm in February, Mr. Wallace and his father volunteered to drive out to residents trapped in their homes.
“When we are called to action, we forget about those differences and just do the right thing,” she said. Shannon Medical Center currently has 70 percent of its intensive care beds full. This August, Tom Green County, which contains San Angelo, has seen its seven-day average of new cases rise to the highest level since November 2020, according to a New York Times database.
Russell Wallace, who also came down with Covid-19, said that he was in the hospital with his son for 13 days, but his condition has improved enough for him to return home.
Despite his own illness and his son’s dire condition, Mr. Wallace said he still firmly believes that masks are ineffective and that the government should not mandate masks or vaccinations. He himself, however, has decided to “look into” getting the shots.
“Personally for me, I’m not so hesitant about the vaccinations now,” he said. “I’ve stared down that barrel and quite honestly, it scared the hell out of me.”