Evidence is growing that having COVID-19 may not protect against re-infecting with new variants. People with older versions of Coronavirus may also have a second infection if they first start a weak defense campaign, new research suggests.
Prolonged immunity from natural infections is one of the big questions in the epidemic. Scientists still think that reintegration is quite rare and usually less severe than early ones, but recent developments around the world have raised concerns.
In South Africa, a vaccine study found new infections with a change in 2% of people, an earlier version of the virus.
In Brazil, many similar cases were documented with a new version. Researchers are exploring whether this helped explain the recent increase in the city of Manaus, where three-quarters of the residents were previously thought to be infected.
In the United States, a study found that 10% of marine recruits had evidence of prior infection and tested negative repeatedly before beginning basic training that had become infected again. The work was done before the outbreak of the new variants, a study leader said, at Mount Sinai of New York’s Econ School of Medicine. Stuart Sealfon.
“The previous infection does not give you a free pass,” he said. “There remains substantial risk of rescheduling.”
Reinfections are a public health concern, not just a personal one. Even in cases when there are no symptoms of re-infection or are only mild, people can still spread the virus. Health officials are therefore urging vaccination as a long-term solution and encouraging people to wear masks, maintain physical distance, and wash their hands frequently.
The US government’s top infectious disease specialist, Dr. Anthony Fauci said, “This is the incentive to do what we’re saying: the more people we can vaccinate and the quicker it can work.”
Fauci said, “I notice when I look at the figures … and I’d like to suggest … a vaccine-induced preservation may be a little better”.
Doctors in South Africa began to worry when they saw an increase in cases at the end of last year in areas where blood tests showed that many people already had the virus.
Until some time ago, all indications were “that previous infections provide protection for at least nine months,” so the second wave should have been “relatively submissive”, Dr. of the University of Johannesburg. Shabir Madhi said.
Scientists discovered a new version of the virus that is more contagious and 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 trial of Novavax’s vaccine and found it less effective than the new version. The study also showed that infection with the new version was common in those who had COVID-19, and those who did not.
“What this basically tells us, unfortunately, is that South Africa does not protect against previous infections with early variants of the virus”, against new ones.
In Brazil, hospitalization in Manaus in January led to similar concerns and a new version appeared that is more contagious and less sensitive to certain treatments.
“One of these cases could be a driver,” said Dr. Esther Sabino of the University of Sao Paolo. He wrote an article in Lancet magazine On the possible explanation. “We are not yet able to define how often this is happening,” she said.
California scientists are also investigating whether a recently identified variant could cause disturbances or a surge in cases there.
“We’re looking at that time,” said Jasmine Plummer, a researcher at Cedars-Sinai Medical Center in Los Angeles.
The editor-in-chief of the Journal of the American Medical Association, Dr. Howard Boucher said he would soon report on what he called the “Los Angeles version”.
Sirinfon said that the new variants were not responsible for the disturbances observed in the study of marines, this was done before the emergence of the muted virus. Other findings of the study were published in the New England Journal of Medicine; New people on reinfection are posted on a research website.
The study involved several thousand Marines recruits who tested negative for the virus three times during a two-week monitored military quarantine before beginning basic training.
Of the 189 whose blood tests showed they had been infected in the past, 19 tested positive again during six weeks of training. This is much lower than those without previous infections – “about half of them got infected at the basic training site,” Sealfon said.
The quantity and quality of antibodies that previously infected marines were associated with their risk of recurrence of the virus. Sealfon said that any disturbances of any kind do not cause serious illness, but that does not mean that recruits were not at risk of spreading the infection.
“It seems that reconstruction is possible. I don’t think we fully understand why this is so and why immunity has not developed “, in those cases, said an immunological expert with no role in the study, E. John Wheeree of the University of Pennsylvania.
“Natural infections can leave you with a threshold of immunity” while vaccines consistently induce high levels of antibodies, Jori said.
“I’m optimistic that our vaccines are doing a little better.”
___
The Associated Press Department of Health and Sciences has support from the Science Education Department of the Howard Hughes Medical Institute. AP is solely responsible for all content.
.