Antibodies against cold help against COVID-19

A research team at the University of Zurich (UZH) has come closer to answering why some people experience severe disease courses with COVID-19 while others do not. They have identified a component that contributes to immunity aside from infection with SARS-CoV-2 or vaccination; Alexandra Trkola, Head of the Institute of Medical Virology at the UZH, is quoted in a press release, stating: “People who have had strong immune responses to other human coronaviruses also have some protection against SARS-CoV-2 infection.”

This is called cross-reactivity. It also occurs with T cell response, which is the second pillar of the human immune system. Even when protection is no longer complete a few months after vaccination or recovery, “cross-reactive immune responses shorten the infection and reduce its severity”.

This result was achieved with a test procedure that the team had developed specially. The researchers investigated the levels of various antibodies in the serum of 825 blood donors taken before the pandemic. They also tested 389 samples from donors who had been infected with SARS-CoV-2. Combined with computer-based models, these analyses enable accurate predictions of how well the antibodies bind to invading viruses and neutralize them according to the UZH.

The study shows that people who had been infected displayed lower levels of antibodies against the coronaviruses that cause common colds. At the same time, those who had caught COVID-19 who had high levels of antibodies against the harmless coronaviruses were hospitalized less frequently. Furthermore, it is also possible that SARS-CoV-2 immunity also provides a certain protection against infection with other coronavirus.