For the past three decades, Dr. Toni Darville has treated some of the sickest children suffering from viral illnesses — especially the flu.
"I've seen a lot of kids become extremely ill after influenza," said Darville, chief of pediatric infectious diseases at the University of North Carolina Children's Research Institute. Some have developed pneumonia. Others needed to be placed on machines called ECMO to help their damaged heart and lungs heal.
But the Covid-19 pandemic has been different. Darville estimates that she has seen about the same number of severely ill kids with the coronavirus in a single season as she has over 30 years of treating seriously ill kids with flu.
"I just don't think the lay public understands the gravity and intensity of this virus," she said.
While children in general have been spared the worst impact of Covid, they can, in rare instances, become seriously ill and in some cases die. While politicians and school districts battle over mask mandates for children, doctors on the front lines want parents to understand Covid is different than the flu.
"There are more differences between the seasonal flu and Covid-19 than there are similarities," Dr. Kavita Patel, a primary care physician in Washington, D.C., and a former health policy director under President Barack Obama, said on NBC's "Nightly News" this week.
Influenza is well-understood, while the virus that causes Covid has been known to humanity for less than two years. Questions remain about how to best treat kids who are seriously ill with Covid, and about whether they’ll develop lasting problems related to the virus.
Flu shots are widely available to all kids, while no Covid vaccines have been authorized for children under 12. More than half of children — 60 percent — get their flu shot each year, which doctors say helps prevent hospitalization and death. The vast majority of kids who die from the flu are unvaccinated.
Complicating matters is the hypercontagious delta variant, which swept through the country in July and now accounts for more than 90 percent of new cases. It remains unclear if the variant — which is more transmissible than the seasonal flu — causes more severe illness in kids, but doctors are reporting that they're seeing more children in the hospital than at any point in the pandemic. (Even getting a clear picture on hospitalizations is difficult, as only 23 states, plus New York City, break down their hospitalizations by age, according to the American Academy of Pediatrics.)
Flu vs. Covid
The unpredictable nature of which kids will get very sick from Covid is of particular concern to doctors.
Doctors have a good understanding of who is most at risk for severe illness from flu. They include babies too young to get the flu shot, as well as kids with chronic health conditions, such as asthma and diabetes, according to the Centers for Disease Control and Prevention.
Most pediatric flu deaths are in kids who have underlying health problems, said Dr. Andi Shane, chief of the division of pediatric infectious diseases at the Emory University School of Medicine.
About half of the children hospitalized with Covid also have underlying medical problems, such as obesity and asthma, said Dr. Yvonne Maldonado, chair of the American Academy of Pediatrics' Committee on Infectious Diseases, as well as the chief of the division of pediatric infectious diseases at the Stanford University School of Medicine.
But that also means that half do not have an underlying condition, she said — making it "difficult to predict which healthy children will experience severe infections."
The range of symptoms and complications also vary. "Influenza makes you sick," Darville said. "Children come into the hospital with flu pneumonia, and, rarely, one will die."
But Covid can cause other complications, she said, ranging from "horrible diarrhea, very high fevers" to a type of heart inflammation called myocarditis. And mild or even asymptomatic Covid cases in kids can lead to a dangerous inflammatory condition called multisystem inflammatory syndrome in children, or MIS-C, that occurs several weeks later. Little is known about the effects of long Covid, which causes lingering symptoms, in kids.
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Covid cases are rising steadily in children, most of whom remain unvaccinated. The week of July 29, the American Academy of Pediatrics reported 93,824 pediatric Covid cases, up from 71,726 the week before.
As cases go up, hospitalizations will likely follow. Doctors are already feeling the strain from an unseasonal surge of winter viruses in the summer, including RSV, or respiratory syncytial virus, which is landing an unusual number of children in intensive care units.
Rising Covid cases are set to collide with the start of the school year, while fights about mask use continue. Doctors say they're worried about what will happen as large numbers of unvaccinated children go back to school this fall and winter.
"I would imagine that with Covid on top of everything else, we're gonna be very busy in the hospital," Darville said.