Two studies released by CDC last week found that hospitalization rates for Covid-19 among children have risen sharply due to the spread of the delta variant.

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Covid-19 hospitalizations for children, teenagers rise sharply

In one of the studies, researchers looked at data from the Covid-Net surveillance network, which includes hospitalization data from 99 counties in 14 states. They found that, between late June and mid-August, Covid-19 hospitalization rates among children and teenagers rose almost fivefold—and hospitalization rates were 10 times higher in unvaccinated adolescents compared to vaccinated adolescents.

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The researchers also found that in recent months, Covid-19 hospitalization rates among children have been steadily climbing, especially among children age four or younger. For the week ending in Aug. 14, hospitalization rates among children four and younger were at 1.9 per 100,000, almost 10 times higher than the rates of late June.

Among children and adolescents hospitalized between June 20 and July 31, the study found 23.2% ended up in the ICU, while 9.8% required ventilation and 1.8% died. These rates, as a share of all adolescents hospitalized, were around the same as they were before the delta variant spread.

In the other study, researchers looked at data from two national surveillance systems representing hospitals in 49 states and Washington, D.C. They found that, since July when the delta variant became dominant in the United States, Covid-19 cases, ED visits, and hospital admissions among children 17 and younger have risen much more sharply in less-vaccinated states.

Specifically, the researchers found that ED visits related to Covid-19 and hospital admissions among children in states with the lowest vaccination rates were more than triple the rates in states with high vaccination rates.

David Siegel, lieutenant commander in the U.S. Public Health Service and lead author on the study, said it's possible "that delta is more severe or that delta is more transmissible, and it could be related to other factors such as masking."

'Community-level vaccination coverage protects our children'

CDC Director Rochelle Walensky said, "What is clear from [this] data is community-level vaccination coverage protects our children."

She added, "As the number of Covid-19 cases increase in the community, the number of children getting sick, presenting to the [ED] and being admitted to the hospital will also increase." (Scully, The Hill, 9/3; Goldberg/Anthes, New York Times, 9/3; Doherty, Axios, 9/4)