Pediatric hospitalizations for COVID-19 have soared over the summer as the highly contagious delta variant spread across the United States, according to two new studies from the Centers for Disease Control and Prevention. From late June to mid-August, hospitalization rates in the United States for children and teenagers increased nearly fivefold, although they remain slightly below January's peak, one new study found. But vaccination has made a difference. During this summer's wave, the hospitalization rate was 10 times as high in unvaccinated adolescents as in those who were vaccinated, researchers found. Pediatric hospital admissions were nearly four times as high in states with the lowest vaccination rates as in those with the highest rates, according to a second study. The studies, released Friday, do not provide clear answers about whether Delta causes more severe disease in children than earlier versions of the virus. The rise in pediatric hospitalizations could also be because of the variant's high infectiousness. Indeed, one study concluded that the proportion of hospitalized children with severe disease had not changed in late June and July, when the Delta variant became dominant in the United States. The rates reported in the CDC studies are based on data from two national surveillance systems, including hospitals in 49 states and Washington, D.C. In one CDC study, researchers found that since July, the rate of new coronavirus cases increased for children 17 or younger, as did COVID-19-related emergency room visits and hospital admissions. "We saw that ER visits, cases and hospital admissions are rising," said Dr. David Siegel, lieutenant commander in the U.S. Public Health Service and the lead author of the paper. "It could be that Delta is more severe or that Delta is more transmissible, and it could be related to other factors such as masking." The study also found that COVID-19-related emergency room visits and hospital admissions among children were more than three times as high in states with the lowest vaccination coverage compared with states with high vaccination rates, underscoring the importance of communitywide vaccination to protect children. Other important factors that might affect regional differences included masking and social distancing measures, the study noted. In a second study, researchers analyzed data from the COVID-NET surveillance network, which includes information on hospitalizations in 99 counties across 14 states. Over the course of the pandemic — or from March 1, 2020, to Aug. 14, 2021 — there were 49.7 COVID-19-related hospitalizations per 100,000 children and adolescents, the researchers found. But the weekly rates have been climbing since July. During the week ending Aug. 14, there were 1.4 COVID-19-related hospitalizations for every 100,000 children, compared with 0.3 in late June and early July. (That remains slightly below the peak weekly rate of 1.5 hospitalizations per 100,000 children, in early January 2021, in the post-holiday wave of cases.) Hospitalization rates have increased most sharply for children who are 4 or younger. In the week ending Aug. 14, there were 1.9 hospitalizations per 100,000 children in that age group, nearly 10 times as many as in late June. — Agencies
