Testing negative for coronavirus antibodies doesn’t mean you’re not immune to COVID-19, according to a new study.
The new study — which came from researchers at Karolinksa Institute in Sweden — found for every one person who tested positive for antibodies, two people were found to have T-cells that can identify and destroy infected calls.
People with those T-cells had mild or symptomless COVID-19 cases, BBC News reports.
BBC News said: “But it’s not yet clear whether this just protects that individual, or if it might also stop them from passing on the infection to others.”
The researchers tested 200 people for T-cells and antibodies. Some had donated blood. Others came from those first infected in Sweden or had returned from Italy.
According to BBC News, this might mean some have more immunity to the virus than we think. Or, the antibodies had left their system when the tests were done.
“T cells are a type of white blood cells that are specialised in recognising virus-infected cells, and are an essential part of the immune system,” says Marcus Buggert, assistant professor at the Center for Infectious Medicine, Karolinska Institutet, and one of the paper’s main authors. “Advanced analyses have now enabled us to map in detail the T-cell response during and after a COVID-19 infection. Our results indicate that roughly twice as many people have developed T-cell immunity compared with those who we can detect antibodies in.” — Marcus Buggert, assistant professor at the Center for Infectious Medicine, Karolinska Institutet, and one of the paper’s main authors.
Another study suggests antibodies may die soon
- A study published in June suggested that coronavirus antibodies could last two to three months once someone becomes infected with COVID-19, as I wrote about for the Deseret News.
- The study — published in Nature Medicine — found antibodies only lasted two to three months with some patients.
- CNBC said: “Scientists say they are still learning about key aspects of the virus, including how immune systems respond once a person is exposed. The answers, they say, may have large implications for vaccine development, including how quickly it can be deployed to the public.”