Kids in Boston and Philadelphia are now showing strange symptoms of the coronavirus, but experts say it remains 'exceptionally uncommon'

Doctors across the globe are expressing concern about a strange new set of symptoms in kids. Here's what we know so far. (Getty Images)
Doctors across the globe are expressing concern about a strange new set of symptoms in kids. Here's what we know so far. (Getty Images)

The first warning about a mysterious syndrome in kids — potentially linked to the coronavirus — came from England’s National Health Service (NHS) on April 27. The alert, marked urgent, warned doctors that the country had seen a sudden rise in children presenting with a “multi-system inflammatory state” requiring intensive care and noted that there was “growing concern” that it may be connected to COVID-19.

In the week and a half since, more cases have been confirmed not only in Europe but in New York, where the New York State Department of Health has confirmed 64 suspected cases of what they referred to as “Pediatric Multi-System Inflammatory Syndrome Associated with COVID-19.” Two additional pediatric departments — one in Philadelphia and another in Boston — both confirmed to Yahoo Life that they have seen suspected cases, as well.

Many health experts have noted that the symptoms, such as high, sustained fever (above 102 degrees), conjunctivitis, rash, abdominal pain and diarrhea, seem to overlap with two existing conditions: toxic shock syndrome and Kawasaki disease.

While the development may seem alarming, multiple pediatricians say that this strange constellation of symptoms is not necessarily a cause for panic. “So far, this seems to be a very rare event,” says Dr. Nipunie Rajapakse, a pediatric infectious disease physician at the Mayo Clinic who is investigating the new illness. “I think there have been a few dozen cases reported in Europe, and we’re still learning about cases here.”

As pediatricians continue to search for answers, here is what we know about the symptoms thus far.

Many of the kids are testing positive for antibodies but not the virus

Although some headlines have described the condition as a response to the coronavirus, Rajapakse notes that it has appeared most frequently at this point in kids without an active COVID-19 infection. “From the limited reports that we have so far, there seem to be more kids who have tested positive for the antibody to the virus rather than the actual virus itself,” says Rajapakse. “It suggests that maybe this is more of a kind of delayed process rather than at the time of the initial infection.”

Dr. Audrey John, head of the pediatric infectious diseases division at Children’s Hospital of Philadelphia, has seen this firsthand. “Many of the children don’t have the virus in their nose anymore, and that suggests they’re not actively infected in their respiratory tract the way that adults who are coming in sick are,” John tells Yahoo Life. “We will find out when the research shows, but my guess is that these kids had [a COVID-19] infection, did perfectly fine, and now that their body has mounted an adaptive immune response — this very robust sort of out-of-control inflammation.”

Symptoms align with Kawasaki disease and/or toxic shock syndrome

In the initial NHS alert, the organization wrote that the cases had “overlapping features” of both toxic shock syndrome (TSS, a rare, life-threatening bacterial infection) and Kawasaki disease (KD, a rare inflammatory condition in children under 5). While TSS — commonly associated with tampons — is a well-known condition in the United States, Kawasaki disease is not. The condition was first discovered in Japan in the late 1960s and involves inflammation of the blood vessels, causing symptoms such as fever, rash, conjunctivitis, swollen tongue, swelling or redness of the hands and feet, and lymph node enlargement in the neck. Later symptoms of the illness — typically two to three weeks in — include abdominal pain and diarrhea.

Experts are still uncertain exactly what causes Kawasaki disease but have hypothesized that it may be triggered by a virus. John says that many of the cases connected to COVID-19 in kids seem to have more features of Kawasaki disease than TSS — but that there’s a reason pediatricians are discussing both.

“When you see a teenager with a high fever and a weird rash and low blood pressure and shock, that looks a lot like toxic shock,” John tells Yahoo Life. “But then [some cases] have gone on to have other features of Kawasaki’s like red eyes or cracked lips or swollen hands. So there’s a lot of overlap between the way that Kawasaki looks and toxic shock looks, and if we’re confused we treat for both, essentially because you really can’t tell right away which direction it’s going to go.”

Dr. Jennifer Lighter, assistant professor of pediatrics and a hospital epidemiologist at NYU Langone Health, confirms that she has seen at least four suspected patients with these symptoms, including one teen with a “toxic shock-like COVID picture.”

Kawasaki typically resolves within 6 weeks but in rare cases can cause long-term complications

An estimated 3,000 kids in the U.S. are diagnosed with KD each year, the majority of whom fully recover through a plasma treatment known as intravenous immunoglobulin, or IVIG. John’s team has been administering IVIG to the kids with COVID-related inflammatory syndrome, and she says thus far — like most with KD — they have been “very responsive” to the medicine. Rajapakse agrees that IVIG is typically “very effective in shutting down this inflammatory response.”

While most kids will recover within six weeks, Rajapakse says the major complication that concerns doctors is the inflammation of the coronary arteries. “Sometimes this can cause a weakening in the walls of those arteries resulting in something called a coronary artery aneurysm,” says Rajapakse. Lighter notes that the key is seeking treatment immediately. “Children are treated with IVIG as well as aspirin. Steroids are also used for severe cases,” she tells Yahoo Life. “Without treatment a quarter of children will progress to coronary artery aneurysms.”

It seems unlikely to be the product of a mutated virus

Despite early suggestions that the rise of new symptoms may signal a mutation in the SARS-CoV-2 virus, the fact that the kids are showing COVID-19 antibodies makes it unlikely. “I think the reason that these cases are popping up now is more an artifact of where we are in the outbreak rather than any sort of significant mutation,” says Rajapakse. “People are kind of periodically looking at viral genetic sequences and looking for major changes or mutations, which we haven’t really seen yet ... so I think this is more so happening just because of the point that we’re at in the outbreak.”

John agrees. “I think the reason that we’re seeing these cases after the peak of infections in adults is that this is not happening at the time of their acute infection, so these kids didn’t just now get infected with SARS-CoV-2; they were infected — we don’t know for sure — maybe a month ago,” says John. “And this is really a crazy immune response to the virus.”

Pediatricians consider it an “exceptionally uncommon outcome”

The new reaction has made headlines across the globe, but John stresses that it’s not a call for panic. “This is obviously still a very, very rare presentation,” she says, adding that she has heard of approximately 30 cases in Europe, 15 in New York and under two dozen others. “We’re talking less than a hundred children, even though we know there have been millions of cases of COVID-19,” John says. “So I think we can all be pretty reassured that this is an exceptionally uncommon outcome for children.”

Rajapakse says that experts are working to sort out exactly what the clinical features are and how many cases are connected to the coronavirus. “Based on all the kids that have tested positive [for COVID-19] in the United States, it is definitely rare,” she says. John adds that parents should be aware of the risks, but not frantically googling symptoms. “I don't think any parent's going to miss this,” says John. “It's fever — high spiking fevers [above 102] — that don't go away.”

For the latest coronavirus news and updates, follow along at According to experts, people over 60 and those who are immunocompromised continue to be the most at risk. If you have questions, please reference the CDC’s and WHO’s resource guides.

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