Studies find nearly 300 kids with inflammatory condition tied to Covid-19 - STAT

research groups have reported finding nearly 300 cases of an alarming apparent side effect of Covid-19 in children, a condition called multisystem inflammation syndrome, or MIS-C.

While researchers have previously reported on the condition, the papers mark the first attempt to measure how frequently the side effect occurs and how it affects children who develop it.

The studies, published in the New England Journal of Medicine, describe children who develop severe inflammation affecting multiple organ systems after having had Covid-19, sometimes between two and four weeks after the infection.

In one of the studies, led by researchers at Boston Children’s Hospital, 80% of the children who developed the condition required intensive care, 20% required mechanical ventilation, and four children, or 2%, died.

In the second study, from researchers from New York state, a similar percentage of 99 children who developed the syndrome required ICU care and two children died.

But in late April, doctors in London alerted the world to the possibility that some children who had Covid-19 appeared to go on to develop something that looked like Kawasaki’s disease, an inflammatory condition that can attack the heart.

In mid-May, the CDC asked doctors across the country to be on the lookout for cases of multisystem inflammatory syndrome in children.

Another difference: While KD disproportionately affects children of Asian descent, MIS-C cases in the New York cohort were of all racial and ethnic backgrounds, the researchers reported.

The New York group estimated that the majority of MIS-C cases occurred about one month after the peak of Covid-19 cases in the state.

They estimated that between March 1 and May 10, two of every 100,000 people under the 21 years of age who had laboratory-confirmed SARS-CoV-2 virus developed MIS-C in the state.

An editorial written by Michael Levin, from the department of infectious diseases at Imperial College London, said there have been roughly 1,000 pediatric cases of the condition reported worldwide to date.

If MIS-C only occurs in 2 per 100,000 infections under 21 and the rate of infection is that age group is 322 per 100,000 then simple math reveals that 322,000 infections would occur in 100,000,000 under 21 years and thus there would be 6.44 cases od MIS-C in a population of under 21 yrs numbering 100,000,000