What is the new inflammatory syndrome infecting children after COVID-19?

According to WHO, its features are similar to those of Kawasaki disease and toxic shock syndrome.

A French doctor, wearing a protective suit and a face mask, administers a nasal swab to a 6-year-old child during a COVID-19 testing in Gouzeaucourt, during the outbreak of the coronavirus disease (COVID-19) in France, May 16, 2020. (photo credit: PASCAL ROSSIGNOL/REUTERS)
A French doctor, wearing a protective suit and a face mask, administers a nasal swab to a 6-year-old child during a COVID-19 testing in Gouzeaucourt, during the outbreak of the coronavirus disease (COVID-19) in France, May 16, 2020.
(photo credit: PASCAL ROSSIGNOL/REUTERS)
Manifestations of COVID-19, the disease caused by the novel coronavirus, are generally milder in children. But recently, reports from Italy, Europe and now North America have described children and teens who require admission to intensive care units with a multisystem inflammatory condition, the World Health Organization said.
 
What is this new inflammatory syndrome that is infecting children after coronavirus?
 
According to the WHO, its features are similar to those of Kawasaki disease – an acute and usually self-limiting vasculitis of the medium calibre vessels, which almost exclusively affects children – and toxic shock syndrome – a rare, life-threatening complication of certain types of bacterial infections. Initial hypotheses are that this syndrome, now being referred to as Pediatric inflammatory multisystem syndrome temporally associated with COVID-19 or in short PIMS-TS, may be related to the novel coronavirus.
 
According to Dr. Galia Rahav, head of the Infectious Disease Unit and Laboratories at Sheba Medical Center, Tel Hashomer, there have been three known cases in Israel and so far, none of them have died. There was also a case of an adult who was treated at Sheba last week who presented similar symptoms.
 
The first time PIMS-TS appeared in scientific literature was in early May when about 15 cases were reported in New York, said Dr. Efraim Bilavsky, head of the coronavirus program at Schneider Children’s Hospital. To date, there have been around 70 cases reported in New York, but he cautioned that this number tells us little about what percentage of coronavirus infected children come down with the syndrome.
 
“It is a syndrome for which we do not know its exact incidence,” Bilavsky said. “It is clear that many children [in New York] have been infected with the coronavirus and have not been tested. So, when there are alleged reports of 70 cases in New York, we do not know out of how many infected. Is it common? Is it rare? If so, how rare? We do not know.”
 
The American children were all hospitalized with fever and inflammation. Some had rashes, abdominal pain, vomiting or diarrhea. Respiratory involvement has been reported in less than half the cases.
 
All of the children were tested for the novel coronavirus using two types of tests, molecular and serological. Four of the children were found to have active cases of the virus. Six were found negative but positive for antibodies, meaning they had the virus in the past. Five did not have nor had coronavirus.
 
WHO developed a preliminary case definition for PIMS-TS and said that children with the syndrome have at least two of the following systems: rash, hypotension or shock, cardiac arrhythmia, evidence of coagulopathy, or acute gastrointestinal problems. In addition, they have elevated markers of inflammation but no other obvious microbial cause of inflammation, and have either had coronavirus or been in contact with someone who did.
 
Bilavsky said that Kawasaki disease is much more common among Asian children and “there may be different populations that will have different incidences of the new syndrome. The impression is that there are more cases in England and New York than elsewhere. I hope that Israeli children will not get sick."
 
Should parents panic?
 
Bilavsky said that “scary reports, stressful headlines and incorrect data help sell newspapers,” and that there are known treatments available for this type of sickness if caught early. He said parents should be cautious and take their children’s temperature regularly. If children have a high fever for more than three days, they should be brought to the emergency room.
Rahav added that it is expected that as children return to school, they will pick up viruses and colds and parents should not jump to the conclusion right away that their child has PIMS-TS.
 
“Is this new syndrome a reason to stay home and resume lockdown?” Bilavsky asked. “Of course not. Is it a reason not to send the children to school or preschool kindergarten when we have new individual cases every day someone new is infected with corona? Of course not.”