High levels of T-cells from common cold coronaviruses can provide protection against COVID-19, an Imperial College London study published on Monday has found, which could inform approaches for second-generation vaccines.
Immunity against COVID-19 is a complex picture, and while there is evidence of waning antibody levels six months after vaccination, T-cells are also believed to play a vital role in providing protection.
The study, which began in September 2020, looked at levels of cross-reactive T-cells generated by previous common colds in 52 household contacts of positive COVID-19 cases shortly after exposure, to see if they went on to develop infection.
It found that the 26 who did not develop infection had significantly higher levels of those T-cells than people who did get infected. Imperial did not say how long protection from the T-cells would last.