An Old Problem: How Immune Responses Weaken with Age

April 12, 2021

(Knowable Magazine) – As cases and deaths from the coronavirus pandemic rise, one trend remains consistent: The virus is deadliest for older adults. Eight in 10 Covid-19 deaths in the United States have been among adults 65 or older, according to a mid-March report from the Centers for Disease Control and Prevention. Older adults, of course, are more likely to have existing medical conditions and weakened respiratory systems — two major risk factors for becoming severely ill from infection by SARS-CoV-2, the virus that causes Covid-19. But scientists believe that another factor in the observed heightened risk is likely the general decline in the immune system that’s seen with age. In medicine, it has long been known that older immune systems struggle to fight off infections.