After recovering from a corona infection, many people feel as if nothing can happen to them anymore. But the idea of ??super immunity is not only deceptive, but wrong, as a US study shows.
While fewer and fewer people have never had a corona infection, the number of people who have been infected with the virus for the second or even third time is increasing. A new study from the USA shows that these renewed infections often have serious health consequences.
Researchers from Washington University School of Medicine in St. Louis and the Veterans Affairs St. Louis Health Care System found that repeated Sars-CoV-2 infections increase the risk of health impairments in several organ systems. These include hospitalization, lung, heart, brain, blood, musculoskeletal, and gastrointestinal diseases, and even death. Reinfection also contributes to diabetes, kidney disease, and mental health problems. The results were published in “Nature Medicine”.
For the study, approximately 5.8 million anonymized medical records in a database maintained by the US Department of Veterans Affairs, the largest integrated healthcare system in the United States, were analyzed. The patients represented multiple age groups, ethnic groups and genders.
This included 5.3 million people who did not test positive for corona infection from March 1, 2020 to April 6, 2022. During the same period, researchers also assembled a control group of more than 443,000 people who had tested positive, as well as another group of nearly 41,000 people who had two or more documented infections. Of the latter group, most people had two or three infections, few had four infections, and none had five or more infections.
Statistical models were used to examine the health risks of re-infections within the first 30 days after infection and up to six months afterwards. The study considered Covid-19 variants such as Delta, Omicron and BA.5.
Overall, the research team found that people with Covid-19 reinfections were twice as likely to die and three times more likely to be hospitalized than those without reinfection. In addition, people were three times more likely to develop lung problems than those who had only been infected with the virus once. Negative results occurred in both the unvaccinated and those vaccinated prior to reinfection.
Clinical epidemiologist Ziyad Al-Aly, who is one of the authors of the study, is quoted in a statement by the School of Medicine as saying that a sense of invincibility has spread in recent months, “especially among people who are have had an infection and have also been vaccinated”. Some speak of a kind of super immunity against the virus, says Al-Aly. However, the study has shown that a second, third or fourth infection leads to additional health risks in the acute phase and in the months thereafter.
The risk seems to increase with every infection. “This means that even after two Covid 19 infections, it is better to avoid a third,” said Al-Aly. “And if you’ve had three infections, you should avoid the fourth.” The researchers advise taking all approved booster shots and staying at home if you are sick. Also, they recommend the flu shot to reduce the chance of having a twin pandemic of Covid-19 and flu this winter season.
