Jan 5 (Reuters) - The U.S. Centers for Disease Control and Prevention (CDC) said on Wednesday it expanded the eligibility of Pfizer Inc (PFE.N) and BioNTech SE"s booster doses to those 12 to 15 years old. The move came after a panel of outside experts advising the CDC voted earlier to recommend booster shots of the COVID-19 vaccine be made available for ages 12 to 15. The CDC"s Advisory Committee on Immunization Practices (ACIP) voted 13 to 1 to recommend that the U.S. health agency support booster shots for those aged 12 to 15 at least five months after their second dose. The panel also said the CDC should strengthen its recommendation for boosters for ages 16 and 17. The agency had previously made the shots available to those teenagers, but had stopped short of suggesting that all of them should receive the additional jab. The CDC said in a statement it now recommended that adolescents age 12 to 17 years old should receive a booster shot 5 months after their initial Pfizer/BioNTech vaccination series. COVID-19 cases in the United States have hit record levels in recent days due to the fast spreading Omicron variant of the virus. Infection rates are surging as many workers and school children return from holiday vacations, raising the prospect of overwhelmed health systems as well as closed businesses and schools. "COVID is overwhelming our hospitals and our children"s hospitals," said panel member Dr. Katherine Poehling, a professor at Wake Forest School of Medicine. "This is a tool we need to use, and help our children through this pandemic." Data from Israel"s Health Ministry presented at the meeting suggested that vaccinated children aged 12 to 15 who were five to six months past their second dose were being infected at the same rate as unvaccinated kids by the Omicron variant of the virus. After receiving a booster shot, the infection rate dropped sharply, according to the data. Dr. Peter Marks, a top regulator at the U.S. Food and Drug Administration, said that it is reasonable to extend the boosters down to 12- to 15-year-olds given the current surge in cases. The FDA had authorized the additional doses for the age group on Monday, but the CDC sign-off was needed before the shots can be administered. "This booster dose will provide optimized protection against COVID-19 and the Omicron variant," CDC Director Rochelle Walensky said in the statement. Some scientists have expressed concerns about the booster shots due to rare cases of heart inflammation called myocarditis that have been linked to both the Pfizer/BioNTech and Moderna (MRNA.O) vaccines, particularly in young men. While there is limited data on myocarditis after booster doses for ages 12 to 15, the FDA has said evidence from both the United States and Israel indicates that the risk of myocarditis in men aged 18-40 is significantly lower after booster shots than after the second vaccine dose. Only two cases of myocarditis were reported in Israel among 44,000 adolescents aged 12 to 15 who received a third dose of the Pfizer/BioNTech vaccine, the Israeli Health Ministry said on Wednesday.