In late April, New York City’s health department officials became aware of a disturbing new public health threat: an illness affecting children that was being linked to coronavirus and known to have caused at least one child’s death in the United Kingdom. Described in an alert by England’s National Health services as a “multisystem inflammatory state,” patients were said to have required intensive care, exhibiting symptoms of both toxic shock syndrome, a rare complication resulting from a bacterial infection, and Kawasaki disease, an illness that causes inflammation of the blood vessels.

At the time, the city had not received any reports about such cases, according to Ellen Lee, a medical director in the division of disease control for the city’s Health Department.

Nor, she added, had health officials noticed any similar alerts in the U.S. on public health listservs.

“The public health community learned about it at the same time that it was hitting mainstream media,” Lee said, in a telephone interview on Sunday.

On April 29th, two days after the U.K. alert, city health officials began the process of making calls, reaching out to all hospitals that had more than five ICU beds for pediatric patients. Then, on May 1st, the city included the information about reports of pediatric cases in the U.K., Italy and some U.S. cities during one of its routine coronavirus webinars, which is attended by roughly 600 to 700 local health providers.

Through the health department’s initial outreach, city officials learned that there were nine cases of pediatric patients in New York City showing symptoms of Kawasaki disease.

Four days later, the city would send its own official alert about the condition, citing 15 hospitalized children ranging in age from 2 to 15 who had been treated in intensive care units. Soon after, the state sent its own advisory announcing dozens of cases.

By the end of last week, Governor Andrew Cuomo had announced that three children in the state, including a 5-year-old from New York City, had died from the disease.

There are now 95 cases statewide, 38 of which are in New York City, of a mystifying disease that has no formal classification in the U.S. Its symptoms have been described as rash, fever, red eyes, red lips and a swollen or “strawberry” tongue. Many of the children have either tested positive for coronavirus or for the antibodies, suggesting a prior infection.

“Since the beginning, we’ve been in a state of wishful thinking that children were, for whatever reason, by and large protected from the brunt of this virus,” said Dr. Irwin Redlener, the director of Columbia University’s National Center for Disaster Preparedness and a specialist in children’s health.

“There were a few scattered reports of pediatric deaths in China but these, along with reports of children affected elsewhere, represent a minute percentage of the total affected population,” Redlener said, adding, “I am afraid that the impact of covid on kids is just beginning to be understood.”

Even as the list of coronavirus symptoms gets dauntingly longer with each passing week, the news about this new unexplained syndrome has been an unexpected and frightening jolt to parents, who had largely taken comfort in studies that suggested that children were spared from the most severe symptoms of COVID-19. It also comes at a time when the city and state have been on the receiving end of mostly hopeful news. Unlike the rest of the country, coronavirus infections appear to be waning in New York after nearly two months of strict social distancing measures. New hospitalizations for the virus have steadily edged downward, while the death toll on Sunday fell below 200, the first time since March 27.

And although the road to reopening the economy is expected to be lined with minefields, both the city and state have outlined measures to get New Yorkers there. Officials are already starting to set up expectations. Mayor Bill de Blasio has specifically said that he hopes to reopen the city’s public schools in September.

But what happens with this new illness, now officially known as pediatric multisystem inflammatory syndrome, could very well change that calculus of that decision, as well as those involving broader social distancing restrictions as the city heads into the summer and over a million children clamor for places to unleash their pent-up energy.

Should the caseload and fatalities continue to rise and present a new crisis, there will inevitably be questions about whether public health agencies on all levels, from the city’s health department to the World Health Organization, had sufficient coordination and action.

Both the city and state have been criticized for yet another slow-footed response.

NBC NY reporter Melissa Russo, who first pressed city health officials on the growing number of cases of sickened children, tweeted on Friday that it “took both City & State Health Depts many days to get up to speed w/ what pediatricians on frontlines were seeing. My initial sources were alarmed & frustrated that there was no urgency or focus from govt, no alerts for pediatricians & too much nervousness re alarming parents.”

Russo later added that a doctor she spoke to “barely knew what this was a week ago. All the more reason why public health needs to coordinate.”

On Sunday, de Blasio announced that all public school parents would be sent an alert about the new syndrome.

An array of public health agencies spend their time monitoring the pandemic and sharing information globally. But how those organizations communicate and act on information is complicated by local and national protocols that can delay public health actions.

During an April 29th press conference, World Health Officials discussed children in some European countries who appeared to have an inflammatory syndrome similar to Kawasaki disease. But they stressed that the condition was very rare.

Still, in the end, the group concluded the need to collect more data.

“What we’ve asked for is for the global network of clinicians to be on alert for this and to ensure that they capture information on children systematically so that we can better understand what is occurring in children and so that we can better improve our understanding and guide treatment,” said Dr. Maria Van Kerkhove, a WHO scientist.

It is not clear how closely scientists from the U.S. were following European trends. The Centers for Disease Control and Prevention has offices around the world, but the agency still relies on a bottom-up bureaucratic approach, in which it takes its lead from local health authorities.

On Monday—a week after the city’s first alert about the disease went out and only after a request was made by the state—the CDC deployed investigators to New York to examine cases of the new syndrome.

Asked about its efforts to date, a CDC spokesperson said in an email, “At this time as more data are emerging, CDC is working with the Council of State and Territorial Epidemiologists and other domestic and international partners to better understand and characterize this new syndrome, its prevalence and risk factors for it; and to develop a case definition that will allow us to keep track of it.”

As the CDC focuses on New York, a string of cases are now cropping up across the country, from Boston to Los Angeles.

Given that the agency is just starting its investigation, the CDC is yet to issue its own alert, which would give local health authorities guidance on what to look out for.

“There’s no standard case definition,” Lee pointed out.

But concern among doctors has clearly been mounting over the last two weeks. On May 2nd, Boston Children’s Hospital, which has had a handful of patients with the illness, convened a zoom conference of international experts to compare notes. The members of the panel called for more research into the syndrome, including for an immediate investment by government and other health agencies in clinical trials, as well as integration of data on all the children identified as having COVID-19 as well as those with the new inflammatory syndrome.

“If you look at the curves, COVID-19 has plateaued, but there’s an exponential rise in this secondary type of shock syndrome,” said Dr. Jane Newburger, a cardiologist who is an international expert on Kawasaki disease, in a story published on the hospital’s website following the panel. “It is even possible that the antibodies that children are making to SARS-CoV2 are creating an immune reaction in the body. Nobody knows.”