Recent studies have explored the unique protection that many children experience when infected with COVID-19. However, researchers from Yale University explained that some children have developed multi-system inflammatory response (MIS-C) nearly a month after being exposed to the virus.
“Why does this happen when there is no virus or antiviral response still present and in kids?” asked researcher Carrie Lucas. “And why is it only occurring in youth?”
Identifying immune system differences
The researchers analyzed blood samples from four different groups: children and adults unaffected by COVID-19, adults with severe cases of COVID-19, and children with MIS-C.
The blood tests showed significant immune differences between children diagnosed with MIS-C and the other groups involved in the study. While the body is designed to have certain immune responses that protect against infection, MIS-C was associated with higher levels of immune cells called alarmins; though they’re supposed to attack viruses like COVID-19, they can actually harm the body when there are too many of them.
When caught early, the researchers say MIS-C can be treated with medication and isn’t harmful long-term. However, if undetected, an infection can ultimately become life-threatening. In relation to COVID-19, experts have found that roughly 1 in 1,000 children who are diagnosed with the virus, whether a mild or asymptomatic case, have gotten MIS-C more than a month after the initial infection.
Though most kids only experience mild cases of COVID-19 because of the way their immune systems respond to the virus, the researchers explained that it could be this unique immune response that leads to MIS-C.
“Innate immunity may be more active in children who are infected with the virus,” said Lucas. “But on the flip side, in rare cases it may get too revved up and contribute to this inflammatory disease.”