Public health officials in the Midwest and Northeast are sounding the alarm about steep new increases in COVID-19 cases in children.
The increases seem to be driven by greater circulation of more contagious variants, just as children and teens have returned to in-person activities such as sports, parties, and classes.
“I can just tell you from my 46 years in the business, I’ve never seen dynamic transmission in kids like we’re seeing right now, younger kids,” said Michael Osterholm, PhD, who directs the Center for Infectious Disease Research and Policy at the University of Minnesota, Minneapolis.
In earlier surges, children – especially younger children – played only minor roles in transmitting the infection. When they were diagnosed with COVID-19, their symptoms tended to be mild or even absent, and for reasons that aren’t well understood, they haven’t usually been the first cases in households or clusters.
Now, as more SARS-CoV-2 variants have begun to dominate, and seniors gain protection from vaccines, that pattern may be changing. Infectious disease experts are watching to see if COVID-19 will start to spread in a pattern more similar to influenza, with children becoming infected first and bringing the infection home to their parents.
Michigan sees jump in cases
Governors in some hard-hit states are pleading with a pandemic-weary public to keep up mask-wearing and social distancing and avoid unnecessary travel and large gatherings in order to protect in-person classes.
In Michigan, many schools reopened and youth sports resumed just as the more contagious B.1.1.7 variant spread widely. There, cases are rising among all age groups, but the largest number of new COVID-19 cases is among children aged 10-19, the first time that’s happened since the start of the pandemic.
Over the month of March, incidence in this age group had more than doubled in the state. Cases among younger children – infants through 9-year-olds – are also going up, increasing by more than 230% since Feb. 19, according to data from the Michigan Department of Health and Human Services.
The increases have prompted some schools to pause in-person learning for a time after spring break to slow transmission, according to Natasha Bagdasarian, MD, senior public health physician with the Michigan health department in Ann Arbor.
In Minnesota, on a recent call with reporters, Ruth Lynfield, MD, state epidemiologist, said the B.1.1.7 variant, which has rapidly risen in the state, has a higher attack rate among children than that of earlier versions of the virus, meaning they’re more likely to be infected when exposed.
“We certainly get the sense that youth are what we might refer to as the leading edge of the spread of variants,” she said.
Dr. Lynfield said they were tracking cases spreading through youth sports, classrooms, and daycare centers.
In Massachusetts, the largest number of new COVID-19 infections in the last 2 weeks of March was among children and teens. Massachusetts has the fifth-highest number of recorded B.1.1.7 cases in the United States, according to CDC data.
Although most COVID-19 cases in children and teens are mild, the disease can be severe for those who have underlying medical conditions. Even in healthy children, it can trigger a serious postviral syndrome called MIS-C that requires hospitalization.
Emerging studies show that children, like adults, can develop the lingering symptoms of long COVID-19. Recent data from the United Kingdom show 10%-15% of children younger than 16 infected with COVID-19 still had at least one symptom 5 weeks later.
Dr. Osterholm said it remains to be seen whether more cases in children will also mean a rise in more serious outcomes for children, as it has in Europe and Israel.
In Israel, the B.1.1.7 variant arrived at the end of December and became dominant in January. By the end of January, Hadassah Ein Kerem Medical Center in Jerusalem had four patients in its newly opened pediatric COVID-19 ICU unit. They ranged in age from 13 days to 2 years.
By early February, the Ministry of Health warned the country’s doctors to prepare for an “imminent upward trend” in pediatric COVID-19 cases. They notified hospitals to be ready to open more ICU beds for children with COVID-19, according to Cyrille Cohen, PhD, head of the laboratory of immunotherapy at Bar-Ilan University in Ramat Gan, Israel.
On March 31, French President Emmanuel Macron ordered France into its third national lockdown and closed schools for 3 weeks to try to hold off a third wave of COVID-19. President Macron had been a staunch defender of keeping schools open, but said the closure was necessary.
“It is the best solution to slow down the virus,” he said, according to Reuters.
German Chancellor Angela Merkel recently announced a new lockdown for Germany as the spread of the variants has led to rising cases there.
“I think what we’re seeing here is this is going to play out over the country,” said Dr. Osterholm. “Before this time, we didn’t see major transmission in younger kids particularly K through eighth grade, and now we’re seeing that happening with many school outbreaks, particularly in the Northeast and in the Midwest.” He added that it will spread through southern states as well.