Research from Karolinska Institutet and Karolinska University Hospital shows that many people with mild or asymptomatic Covid-19 demonstrate so-called T-cell immunity to the disease.
Marcus Buggert, assistant professor at the Centre for Infectious Medicine, Karolinska Institutet, and one of the paper’s main authors, said: “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.
“Our results indicate that roughly twice as many people have developed T-cell immunity compared to those who we can detect antibodies in.”
Healthy blood donors who gave blood during 2020 and 2019 were also Soo Aleman, who has been testing patients since the start of the outbreak, said: “One interesting observation was that it wasn’t just individuals with verified Covid-19 who showed T-cell immunity but also many of their exposed asymptomatic family members.
The researchers say larger and more longitudinal studies are now needed on both T-cells and antibodies to understand how long immunity lasts.
