(CNN)Repeated capture of Covid-19 can lead to new and sometimes persistent health problems. It seems to be more sexual. Infections, according to the first study on the health risks of reinfection.
Based on the health records of more than 5.6 million people treated with the VA Health System, this study has two or more infections compared to one-time Covid-19 infections. Documented infections were more than twice as likely to die and three times as likely to be hospitalized within 6 months of the last infection. They were also at increased risk of lung and heart problems, malaise, digestive and renal disorders, diabetes and neurological problems.
BA.5 has important mutations that help escape antibodies produced by both vaccines and previous infections, leaving many people vulnerable to reinfection. ..
"If I was asked about reinfection probably a year and a half ago, I would tell you that there might be a patient here or there, but it's really, really rare. That's what Al-Aly said. But that is no longer true.
"So, if you were previously infected with Covid and now have a second infection, I asked a simple question if this really increases the risk. The simple answer is."
Aggregate the risk of reinfection
Al-Aly and his team have more than 250,000 people who once tested positive for Covid-19. I compared my health record with the record. From the other 38,000 people with more than one Covid-19 infection recorded in medical records. More than 5.3 million people with no record of Covid-19 infection were used as controls.
Of the re-infected individuals, 36,000 were infected twice with Covid-19, about 2,200 were infected with Covid-19 three times, and 246 were infected four times.
Common new diagnoses after reinfection included chest pain, arrhythmias, heart attack, inflammation of the heart muscle or sac around the heart, heart failure, and blood clots. Common lung problems include shortness of breath, low blood oxygen, lung disease, and fluid buildup around the lungs, Al-Aly said.
The study also found that the risk of new health problems was highest during the reinfection of Covid-19, but persisted for at least 6 months. There was an increased risk, regardless of whether someone was vaccinated, and it was assessed in stages. In other words, the risk increased with each subsequent infection.
Al-Aly said he didn't expect it to actually happen when he was infected with Covid a second or third time.
"If you had Covid before, the idea is that your immune system is trained to recognize it and is ready to fight it. There are so many, but That's not true. "
Al-Aly said that it doesn't mean that no one has Covid and is doing well. There are many of them. Rather, his research shows that each infection poses a new risk, which increases over time.
He said that even if a person has half the risk of developing persistent health problems during the second infection than during the first infection, the risk of the problem is 50% higher than others. Told. He gets Covid-19 again.
There are some important caveats to this study. Al-Aly says that reinfection was more common among people who were at existing risk due to age and underlying health. This indicates that reinfection may not be random, and the health risks associated withreinfection may also be non-random.
"People who are sick or have immune dysfunction are at increased risk of reinfection and can adversely affect their health after reinfection," Al-Aly said.
He wasn't interested in trying to isolate the pure effects of reinfection, but wanted to understand how repeated infections affect those who get them. is.
"The most relevant question in people's lives is whether they increase the risk of acute complications and long Covids if re-infected, and the answer is clearly yes and yes," he says. I did.
This study is observational and means that the cause and effect cannot be identified.
Al-Aly weighted data before becoming infected with Covid-19 to account for age, gender, drug use, and the underlying health effects of the person, even after weighting the data. Researchers say they have seen an increase in these risks.
Covid-19 continues to be surprised
Experts who were not involved in the investigation said it was convincing.
"There is an idea that many people think so." If I survive the first infection, the second one will really be fine. There should really be no problem. ,'" said Dr. Daniel Griffin, a clinical medicine instructor at Columbia University.
" General wisdom is correct, reinfection is mild, don't worry, look here Is nothing, "Griffin said of his work in the podcast" Virology of the Week. " But that's not really backed up, he said.
This is not the expected method. Even when the form of the virus changes, such as the flu, our immune system generally retains a memory of how to recognize and repel some of the virus. They may still make us sick, but the idea is that our previous immunity is there to implement some kind of defense and protect us from serious harm.
Coronaviruses, especially SARS-CoV-2 coronaviruses, continue to be hit.
"One year later, you can be infected twice with the same coronavirus. The second infection is milder because the coronavirus is inherently capable of interfering with long-lasting lifelong immunity. It's not clear that it could be, "Griffin told CNN.
Griffin says he saw a bidirectional reinfection of Covid-19. Sometimes the second or third is milder for his patient, but sometimes it isn't.
How is it compared to other respiratory infections?
In the early days of the pandemic, he said, people were infected with Covid and three months of considerable protection had passed. But now there is no doubt that these reinfections occur more frequently due to the rapid changes in the virus. He says he has seen people infected four times in the last two years.
"We don't see that much with the flu," Griffin said.
On what people should do now about this risk, Dr. Michael Osterholm, who heads the Center for Infectious Diseases Research Policy at the University of Minnesota, says Americans have really ended up in a pandemic. But that doesn't mean that a pandemic will take place with us.
Osterholm said he had three close friends who recently went to a restaurant for the first time since the pandemic began. All of them were tested positive within 72 hours of the restaurant visit.
He says it's a good time to wear an N95 mask in a public place if you are at high risk of serious illness or just want to avoid getting sick.
"People don't want to hear it, but it's a reality. We're seeing this resurrection and the number of vaccine failures is increasing. Obviously, that's a big concern." He said.