These days, it’s tempting to compare COVID-19 with the common cold or flu. It can similarly leave you with a nasty cough, fever, sore throat—the full works of respiratory symptoms. And it’s also become a part of the societal fabric, perhaps something you’ve resigned yourself to catching at least a few times in your life (even if you haven’t already). But let’s not forget: SARS-CoV-2 (the virus responsible for COVID) is still relatively new, and researchers are actively investigating the toll of reinfection on the body. While there are still a lot of unknowns, one thing seems to be increasingly true: Getting COVID again and again is a good deal riskier than repeat hits of its seasonal counterparts.

It turns out, SARS-CoV-2 is more nefarious than these other contagious bugs, and our immune response to it, often larger and longer-lasting. COVID has a better ability to camouflage itself in the body, “and it has the keys to the kingdom in the sense that it can unlock any cell and get in,” says Esther Melamed, PhD, an assistant professor in the department of neurology at Dell Medical School, University of Texas Austin, and the research director of the Post-COVID-19 program at UT Health Austin. That’s because SARS-CoV-2 binds to ACE2 receptors, which exist in cells all over your body, from your heart to your gut to your brain. (By contrast, cold and flu viruses replicate mostly in your respiratory tract.)