March 11 (UPI) -- There is more evidence why parents of children ages 5 to 15 years should have them vaccinated against COVID-19 after the Centers for Disease Control and Prevention released new data that shows the shots protect against symptomatic illness with multiple virus variants.
Among unvaccinated children infected with the virus' Delta variant, which was the predominant one nationally last summer and fall, 66% reported experiencing symptoms, the data showed.
About half of the unvaccinated young people included in the analysis who were infected with the Omicron variant of the virus, which is the dominant one in circulation now, had symptoms, the agency said.
Conversely, up to five months after receiving their second dose of the COVID-19 vaccine, children ages 12 to 15 years had 87% protection against both symptomatic and asymptomatic infection with the Delta variant, according to the CDC.
They also had 59% protection against infection with the Omicron variant, while fully vaccinated children ages 5 to 11 years had 31% protection against symptomatic or asymptomatic infection with the newer variant up to five months after receiving their second dose, the CDC said.
Still, all fully vaccinated children age 15 years and younger infected with the Omicron variant spent an average of one-half day less sick in bed than those who were unvaccinated, it said.
This new data "adds to the body of evidence that COVID-19 vaccination in eligible children and teens continue to offer protection, particularly against severe COVID-19 disease and during Omicron," the agency said in a statement.
"CDC continues to recommend that all children and teens stay up-to-date on their COVID-19 vaccines, including a booster dose for those who are eligible," it said.
In data released last week, the CDC reported that vaccine effectiveness against hospitalization due to COVID-19 was up to 94% in adolescents ages 12 to 17 years during the Delta surge and up to 74% in children ages 5 to 11 years during the omicron surge.
The new findings are based on an analysis of data on nearly 1,400 children, mostly from Arizona, including more than 1,000 who were ages 5 to 11 years and more than 300 who were ages 12 to 15 years.
Among the participants, 508 had confirmed cases of COVID-19, with 381 infections occurring in children ages 5 to 11 years and 127 reported in those ages 12 to 15 years, the data showed.
Of the confirmed cases of COVID-19 in the study, 386 occurred in unvaccinated children, including 301 in those ages 5 to 11 years, the last group for whom the shots were cleared for use in the United States, the CDC said.
To date, only the two-dose Pfizer-BioNTech vaccine is cleared for use in people age 16 years and younger, though the Moderna shot is currently being evaluated for this group.
The Food and Drug Administration approved the Pfizer-BioNTech vaccine for children ages 5 to 11 years, at a smaller dose, in October.
"The [new] study reinforces the importance of vaccination to keep children and teens protected from severe disease and out of the hospital," the CDC said in a statement.
"COVID-19 vaccination remains a safe and critical tool to protect children and teens regardless of their health status," it said.