More than 10 per cent of young and healthy people who develop severe Covid-19 have misguided antibodies that attack not the virus, but the immune system itself, and another 3.5 per cent may carry a specific kind of genetic mutation, according to a new study. The research, published in the journal Science, noted that both groups of patients lack type I interferon -- a set of 17 proteins crucial for protecting cells and the body from viruses.

More than 10 per cent of young and healthy people who develop severe Covid-19 have misguided antibodies that attack not the virus, but the immune system itself, and another 3.5 per cent may carry a specific kind of genetic mutation, according to a new study. The research, published in the journal Science, noted that both groups of patients lack type I interferon -- a set of 17 proteins crucial for protecting cells and the body from viruses.