What Is COVID Actually Doing to Our Immune Systems?

When the immune system goes awry, it’s bad news. Few, if any, studies have information on the state of patients’ own immune systems before they were infected with COVID, making an apples-to-apples comparison of what COVID does to a particular person’s immune system impossible. In its absence, “the evidence of a long-term impact on the immune system in fully recovered COVID patients, whether mild or severe, is really pretty thin.” “There are some diseases where there is a clear immune signature that would make me worried,” Crotty, the immunologist at the La Jolla Institute, said. But I haven’t seen anything in our data or other studies that makes me worried about long-term impacts on immunity to other infections.” Even if the laboratory studies aren’t conclusive, there is some real-world evidence that mild COVID infections can throw the immune system out of whack. “I don’t think we have a smoking gun at the moment.” Importantly, since none of these studies have pre-pandemic snapshots of participant immune systems, it can’t be ruled out that patients may be more susceptible to developing long COVID if they already had a less-than-healthy immune system, muddling cause and consequence.