Category: COVID-19

AUSTIN, Texas (AP) — Texas will likely partner with the Federal Emergency Management Agency to open two vaccination “super sites” in Dallas and Houston, and more could be on the way, Gov. Greg Abbott said Monday.

Abbott tweeted those vaccine locations would be open every day and operate for eight weeks, handling up to 6,000 shots per day. The governor said adding more sites is possible, but his office did not immediately release further details, including whether that meant Texas would get more vaccine doses or if those sites would pull vaccine from other areas.

The Texas news comes a week after California partnered with FEMA to open two mass vaccination centers under President Joe Biden’s push to create 100 such sites nationwide in 100 days.

According to state health officials, nearly 2.5 million Texans have received at least one dose of vaccine, and nearly 780,000 are fully vaccinated. As of Sunday, Texas had 9,652 COVID-19 patients in hospitals and a death toll of 38,643.

Evidence is mounting that having COVID-19 may not protect against getting infected again with some of the new variants. People also can get second infections with earlier versions of the coronavirus if they mounted a weak defense the first time, new research suggests.

How long immunity lasts from natural infection is one of the big questions in the pandemic. Scientists still think reinfections are fairly rare and usually less serious than initial ones, but recent developments around the world have raised concerns.

In South Africa, a vaccine study found new infections with a variant in 2% of people who previously had an earlier version of the virus.

In Brazil, several similar cases were documented with a new variant there. Researchers are exploring whether reinfections help explain a recent surge in the city of Manaus, where three-fourths of residents were thought to have been previously infected.

In the United States, a study found that 10% of Marine recruits who had evidence of prior infection and repeatedly tested negative before starting basic training were later infected again. That work was done before the new variants began to spread, said one study leader, Dr. Stuart Sealfon of the Icahn School of Medicine at Mount Sinai in New York.

“Previous infection does not give you a free pass,” he said. “A substantial risk of reinfection remains.”

Reinfections pose a public health concern, not just a personal one. Even in cases where reinfection causes no symptoms or just mild ones, people might still spread the virus. That’s why health officials are urging vaccination as a longer-term solution and encouraging people to wear masks, keep physical distance and wash their hands frequently.

“It’s an incentive to do what we have been saying all along: to vaccinate as many people as we can and to do so as quickly as we can,” said Dr. Anthony Fauci, the U.S. government’s top infectious disease expert.

“My looking at the data suggests … and I want to underline suggests … the protection induced by a vaccine may even be a little better” than natural infection, Fauci said.

Doctors in South Africa began to worry when they saw a surge of cases late last year in areas where blood tests suggested many people had already had the virus.

Until recently, all indications were “that previous infection confers protection for at least nine months,” so a second wave should have been “relatively subdued,” said Dr. Shabir Madhi of the University of the Witwatersrand in Johannesburg.

Scientists discovered a new version of the virus that’s more contagious and less susceptible to certain treatments. It now causes more than 90% of new cases in South Africa and has spread to 40 countries including the United States.

Madhi led a study testing Novavax’s vaccine and found it less effective against the new variant. The study also revealed that infections with the new variant were just as common among people who had COVID-19 as those who had not.

“What this basically tells us, unfortunately, is that past infection with early variants of the virus in South Africa does not protect” against the new one, he said.

In Brazil, a spike in hospitalizations in Manaus in January caused similar worry and revealed a new variant that’s also more contagious and less vulnerable to some treatments.

“Reinfection could be one of the drivers of these cases,” said Dr. Ester Sabino of the University of Sao Paulo. She wrote an article in the journal Lancet on possible explanations. “We have not yet been able to define how frequently this is happening,” she said.

California scientists also are investigating whether a recently identified variant may be causing reinfections or a surge of cases there.

“We’re looking at that now,” seeking blood samples from past cases, said Jasmine Plummer, a researcher at Cedars-Sinai Medical Center in Los Angeles.

Dr. Howard Bauchner, editor-in-chief of the Journal of the American Medical Association, said it soon would report on what he called “the Los Angeles variant.”

New variants were not responsible for the reinfections seen in the study of Marines — it was done before the mutated viruses emerged, said Sealfon, who led that work with the Naval Medical Research Center. Other findings from the study were published in the New England Journal of Medicine; the new ones on reinfection are posted on a research website.

The study involved several thousand Marine recruits who tested negative for the virus three times during a two-week supervised military quarantine before starting basic training.

Among the 189 whose blood tests indicated they had been infected in the past, 19 tested positive again during the six weeks of training. That’s far less than those without previous infection — “almost half of them became infected at the basic training site,” Sealfon said.

The amount and quality of antibodies that previously infected Marines had upon arrival was tied to their risk of getting the virus again. No reinfections caused serious illness, but that does not mean the recruits were not at risk of spreading infection to others, Sealfon said.

“It does look like reinfection is possible. I don’t think we fully understand why that is and why immunity has not developed” in those cases, said an immunology expert with no role in the study, E. John Wherry of the University of Pennsylvania.

“Natural infections can leave you with a range of immunity” while vaccines consistently induce high levels of antibodies, Wherry said.

“I am optimistic that our vaccines are doing a little bit better.”

___

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

AstraZeneca’s COVID-19 vaccine does more than prevent people from falling seriously ill — it appears to reduce transmission of the virus and offers strong protection for three months on just a single dose, researchers said Wednesday in an encouraging turn in the campaign to suppress the outbreak.

The preliminary findings from Oxford University, a co-developer of the vaccine, could vindicate the British government’s controversial strategy of delaying the second shot for up to 12 weeks so that more people can be quickly given a first dose. Up to now, the recommended time between doses has been four weeks.

The research could also bring scientists closer to an answer to one of the big questions about the vaccination drive: Will the vaccines actually curb the spread of the coronavirus?

It’s not clear what implications, if any, the findings might have for the two other major vaccines being used in the West, Pfizer’s and Moderna’s.

In the United States, Dr. Anthony Fauci, the nation’s top infectious disease expert, dismissed the idea of deliberately delaying second shots, saying the U.S. will “go by the science” and data from the clinical trials. The two doses of the Pifzer and Moderna vaccines are supposed to be given three and four weeks apart.

Still, the research appears to be good news in the desperate effort to arrest the spread of the virus and also suggests a way to ease vaccine shortages and get shots into more arms more quickly.

The makers of all three vaccines have said that their shots proved to be anywhere from 70% to 95% effective in clinical trials in protecting people from illness caused by the virus. But it was unclear whether the vaccines could also suppress transmission of the virus — that is, whether someone inoculated could still acquire the virus without getting sick and spread it to others.

As a result, experts have been saying that even people who have been vaccinated should continue to wear masks and keep their distance from others.

Oxford’s study, however, found that the vaccine not only prevented severe disease but appeared to cut transmission of the virus by two-thirds. The study has not been peer-reviewed yet.

Volunteers in the study underwent regular nasal swabs. The level of virus-positive swabs — from both those who had COVID-19 symptoms and those who had none – was 67% lower in the vaccinated group.

“That’s got to have a really beneficial effect on transmission,” Oxford lead researcher Sarah Gilbert said at a meeting of the New York Academy of Sciences.

The researchers also looked at how likely people who have been vaccinated are to get a symptom-free infection. In one subset of volunteers, there were 16 asymptomatic infections among the vaccinated and 31 in an unvaccinated comparison group.

Pfizer and Moderna also are studying the effect of their vaccines on asymptomatic infections.

Only the Pfizer and Moderna vaccines are being used in the United States. Britain is using both AstraZeneca’s and Pfizer’s. AstraZeneca’s has also been authorized by the 27-nation European Union. Pfizer has not endorsed the British government’s decision to lengthen the time between doses.

Mene Pangalos, executive vice president of biopharmaceuticals research and development at AstraZeneca, said that no patients experienced severe COVID-19 or required hospitalization three weeks after receiving a first dose, and that effectiveness appeared to increase up to 12 weeks after the initial shot.

“Our data suggest you want to be as close to the 12 weeks as you can” for the second dose, Pangalos said.

British Health Secretary Matt Hancock said the study “backs the strategy that we’ve taken” to make sure more people have gotten at least one shot. Britain’s decision has been criticized as risky by other European countries.

Stephen Evans of the London School of Hygiene and Tropical Medicine said the study’s suggestion that a single dose protected people for 12 weeks was “useful but not definitive.”

He said that the authors themselves acknowledged their research was not designed to investigate the vaccine’s dosing schedule and that their conclusions were based on statistical modeling, not actual patients tracked over time.

“It certainly isn’t very strong evidence, but there is also no indication this is the wrong thing to do,” Evans said of Britain’s strategy.

One of the Oxford researchers, Dr. Andrew Pollard, said scientists also believe the AstraZeneca vaccine will continue to offer protection against new variants of COVID-19, though they are still waiting for data on that. Fast-spreading mutant versions have caused alarm around the world.

“If we do need to update the vaccines, then it is actually a relatively straightforward process. It only takes a matter of months, rather than the huge efforts that everyone went through last year to get the very large-scale trials run,” Pollard told the BBC.

Meanwhile, a U.N.-backed program to supply COVID-19 vaccines to the neediest people worldwide is gearing up after a troubled start. The COVAX Facility announced plans Wednesday for an initial distribution of some 100 million doses by the end of March and more than 200 million more by the end of June to dozens of countries.

Nearly all of the doses expected for the first phase are due to come from AstraZeneca and its partner, the Serum Institute of India. The rollout will be contingent on the World Health Organization authorizing the AstraZeneca shot for emergency use, which is expected to happen this month.

Some 190 countries and territories are participating in COVAX, which has seen rich nations scoop up vaccine supplies, sometimes at premium prices.

The pandemic’s worldwide death toll has eclipsed 2.2 million, including about 447,000 in the U.S., according to Johns Hopkins University data.

New cases per day in the U.S. and the number of Americans in the hospital with COVID-19 have dropped sharply in the past few weeks, but deaths are still running at close to all-time highs at an average of around 3,100 a day. Deaths often lag behind the infection curve, because it can take weeks to sicken and die from COVID-19.

As the Super Bowl approaches, Fauci is warning people against inviting others over for Super Bowl parties, urging viewers to “just lay low and cool it” to avoid turning Sunday’s big game into a super spreader event.

“You don’t want parties with people that you haven’t had much contact with,” he told NBC’s “Today” show. “You just don’t know if they’re infected.”

__

Associated Press reporters Jill Lawless, Maria Cheng, Jamey Keaten and Ricardo Alonso-Zaldivar and contributed to this report.

___

Follow all of AP’s pandemic coverage at https://apnews.com/hub/coronavirus-pandemic, https