Children in Manhattan's Murray Hill neighborhood in New York. Photo: Noam Galai/Getty Images

Solving the mystery of how the coronavirus affects children has gained steam, as doctors try to determine if there's a link between COVID-19 and kids with a severe inflammatory illness, and researchers try to pin down their contagiousness before schools reopen.

Driving the news: New York state's health department is investigating 161 cases of the illness in children. Three youths in the state have died: an 18-year-old girl, a 5-year-old boy and a 7-year-old boy, per Gov. Andrew Cuomo.

Symptoms for patients up to 21 years old, experiencing what doctors are calling "pediatric multisystem inflammatory syndrome" (PMIS), include:

  • Persistent fever and inflammation
  • Abnormal, sudden or rapid heart rhythm
  • Rash
  • Diarrhea and vomiting
  • Weak pulse and rapid breathing
  • Dizziness or loss of consciousness

Doctors have described children "screaming from stomach pain," Jane Newburger of Boston Children's Hospital told the Washington Post.

  • In some, arteries in the heart swelled, similar to Kawasaki disease — a rare condition most often seen in infants and small children that causes blood vessel inflammation, Newburger said.
  • Some affected children have tested positive for coronavirus antibodies, suggesting the inflammation is "delayed," Nancy Fliesler of Boston Children's Hospital wrote in early May.

What's happening: World Health Organization Director-General Tedros Adhanom Ghebreyesus said last week that initial reports suggest the illness affecting some children in Europe and North America "may be related to COVID-19."

  • The CDC has released national criteria for identifying the disease, through a partnership with the New York health department.
  • In New York, initial tests found that 60% of affected children tested positive for the coronavirus, while 40% tested positive for antibodies, Cuomo said.
    • Some children have required cardiac support, over half required mechanical ventilators, and most required blood pressure support, New York City's health department told doctors this month.
    • 30% of the cases in New York have occurred in kids from 5 to 9 years old, per the state health department. 25% of cases have shown in children ages 10-14.
  • Doctors in a hospital in Italy have seen a 30-fold increase of children with severe inflammatory symptoms during the pandemic than they have in the past five years.
  • Doctors in the U.K. reported a rise in April of these symptoms among children, some of whom tested positive for the coronavirus, the country's Pediatric Intensive Care Society said in late April, citing an alert from the NHS. The Lancet published a report earlier this week detailing a cluster of cases.
  • In Asian countries, no cases of PMIS had been reported as of Tuesday — including South Korea, Japan and China, Johns Hopkins said.
  • The Los Angeles Children's Hospital diagnosed three children with the inflammatory syndrome as of this week. Doctors there say it is not contagious.
  • In Delaware, a few cases have occurred over the last few months, a cardiologist with Nemours Children’s Health System told a local NPR affiliate station.
  • Most affected children have responded well to treatment, the WashPost reports.

“I’m thinking of it kind of like the tip of the iceberg,” Jane Burns, a professor of pediatrics at the UC San Diego School of Medicine, told the WashPost. “There’s this very small number of patients, thankfully, who are presenting with this shock syndrome."

The big picture: Early studies from China and the U.S. show that while children of all ages are at risk for the coronavirus, they are experiencing milder complications from the disease than adults, per the Centers for Disease Control and Prevention.

But, but, but: Two recent papers, while not definitive, offer evidence that children can transmit the virus.

  • A report published in the journal Science found that while children have lower infection rates, they have three times as many contacts as adults and about as many opportunities to become infected.
  • A study in Germany, which was not yet peer-reviewed, found that infected children carry at least as much virus as adults, and in some instances, more.

What's next: The CDC is funding a $2.1 million study of 800 children who have been hospitalized after testing positive for the coronavirus through Boston Children's Hospital. The study aims to understand why some children are more vulnerable to the disease.

Go deeper: The coronavirus is a moving target for efforts to tackle it

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Aug 7, 2020 - Health

Cuomo says all New York schools can reopen for in-person learning

Gov. Cuomo on July 23 in New York City. Photo: Jeenah Moon/Getty Images

New York Gov. Andrew Cuomo announced Friday that all school districts across the state can choose to reopen for in-person learning because it has so far maintained low enough coronavirus transmission rates.

Why it matters: It’s another sign that the state, once the global epicenter of the pandemic, has — at least for now — successfully curbed the spread of the virus even as infections have surged elsewhere around the country.

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Data: The Center for Systems Science and Engineering at Johns Hopkins; Map: Axios Visuals

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Why it matters: Health experts believe the true number of COVID-19 cases in African countries is higher than that figure due to a lack of testing and fear that undetected cases could overload some of the world’s weakest health systems.

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Illustration: Sarah Grillo/Axios

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  2. U.S.: Total confirmed cases as of 2. p.m. ET: 4,968,413 — Total deaths: 161,858 — Total recoveries: 1,623,870 — Total tests: 60,415,558Map.
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