A new study indicates that the number of people who have immunity to the coronavirus may be greater than antibody tests suggest.
Research from the Karolinska Institute and Karolinska University Hospital shows that many people with mild or asymptomatic COVID-19 demonstrate so-called T-cell immunity to the disease. This is even if they have not tested positive for antibodies against the virus.
Marcus Buggert, an assistant professor at the Center for Infectious Medicine, Karolinska Institute, and one of the main authors of the article, said: “T cells are a type of white blood cell that specialize in recognizing virus-infected cells, and are essential part of the immune system.
“Advanced analyzes have now allowed us to map the T-cell response in detail during and after a COVID-19 infection. Our results indicate that approximately twice as many people have developed T-cell immunity compared to those in whom we can detect antibodies. “
Read more about immunity to COVID-19:
In the study, which has not been peer-reviewed and has been published as a preprint, the researchers conducted immunological analyzes of samples from more than 200 people, many of whom had mild symptoms or no symptoms of COVID-19.
It involved hospitalized patients at Karolinska University Hospital in Sweden and other patients and their exposed asymptomatic relatives who returned to Stockholm after their vacation in the Alps in March. Healthy blood donors who donated blood during 2020 and 2019 were also included.
Consultant and associate professor Soo Aleman, who has been testing patients since the outbreak began, said: “An interesting observation was that not only people with verified COVID-19 showed T-cell immunity but also many of their exposed members of the asymptomatic family.
“Additionally, approximately 30 percent of blood donors who had donated blood in May 2020 had COVID-19-specific T cells, a figure that is much higher than previous antibody tests have shown.”
Read more news about coronavirus:
Professor Hans-Gustaf Ljunggren at the Center for Infectious Medicine, Karolinska Institutet, and the co-author said the findings were potentially very good news.
He said: “Our results indicate that public immunity to COVID-19 is probably significantly higher than antibody testing has suggested. If this is the case, it is of course very good news from a public health perspective.”
The researchers say that longer, more longitudinal studies on both T cells and antibodies are now needed to understand how long immunity lasts.
Reader questions and answers: Can my immune system fight disease without me realizing it?
Asked by: Jenny Price, Weston-super-Mare
With each new breath, you absorb around 50 potentially harmful bacteria. Virtually all of these are quickly destroyed by your immune system without you feeling anything. But some bacteria and viruses can successfully infiltrate the body and lie dormant without causing any symptoms for many years until they suddenly sprout.
Chlamydia infections, for example, show no symptoms in 50-70 percent of women, because they hide under the radar of the immune system. However, any disease your immune system detects triggers swelling, inflammation, and fever as the disease is fought, so it’s definitely something you’ll notice.
Read more:
