Unvaccinated children aged 5 to 11 years were hospitalized with Covid with twice as many vaccinated children under the winteromicron variant, the Centers for Disease Control and Prevention reported on Tuesday.
The study was the latest to demonstrate that vaccines help keep children out of the hospital with Covid, despite the shots losing some of their strength to stop infections from the Omicron variant.
But the CDC report, based on data from hospitals serving about 10 percent of the U.S. population across 14 states, also offered some of the strongest evidence to date that racial differences in childhood vaccinations may leave black children more prone to serious illness from Covid.
Black children in the age group of 5 to 11 accounted for about one-third of unvaccinated children in the study, the largest of any racial group, and accounted for about one-third of the total Covid-related admissions within the age group.
Estimates from 2020 based on census data suggest that black children made up about 14 percent of U.S. residents ages 5 to 11. However, it is not clear whether the areas covered by the CDC survey are representative of the country’s population, making it difficult to accurately measure any inequalities.
“Increased vaccination coverage among children, particularly among racial and ethnic minority groups disproportionately affected by Covid-19, is crucial in preventing Covid-19-associated hospitalization and serious outcomes,” the CDC study said.
The agency has not reported nationwide data on the race or ethnicity of vaccinated children, making it difficult for researchers to investigate gaps in protection.
Seven states and Washington, DC, report race data for vaccinated children from 5 to 11. Black children were vaccinated at lower rates than white children in most, but not all, of these states, an analysis from the Kaiser Family Foundation found this month. Asian children tended to have the highest vaccination rates, the analysis showed, and Latin American children were inoculated at rates lower than or similar to those of white children.
Among all U.S. residents, blacks are still less likely to be vaccinated than whites, although the difference has narrowed during the vaccination campaign.
Children are protected in much smaller numbers: Only about a third of children from 5 to 11 have at least one vaccine dose, the lowest rate of any age group. And the pace of vaccinations in that age group has dropped significantly in recent weeks.
The CDC study covered the period from mid-December to late February, when about 400 children were admitted with Covid to the selected hospitals participating in the study. Nearly 90 percent of them were unvaccinated. The report said about one-third of the children had no underlying medical conditions, and one-fifth were admitted to an intensive care unit.
Among the children who tested positive for the virus before or during their hospitalization, three-quarters of them were hospitalized primarily for Covid, rather than other diseases, the CDC said.
The agency said Omicron appeared to cause less serious illness in children than the Delta variant, as was the case for adults, but that Omicron was so contagious and infected so many children that they were hospitalized at higher rates during the Omicron climb .
Infected children are far less likely to become seriously ill compared to adults. However, because the youngest children (under 5 years of age) do not yet qualify for vaccination, and older children are vaccinated much lower, children are overall somewhat less protected against the virus than adults.