Researchers link immune dysfunction to long COVID, opening door to new treatments

The study, published Jan. 18 in Science, involved 39 healthy controls and 113 COVID-19 patients who were followed for one year. Blood samples from the 40 COVID patients with long COVID contained signs that the complement system, part of the immune system’s first line of defense against pathogens, never turns off after its encounter with the SARS-CoV-2 virus.