A12-year-old girl receives a first dose of the Pfizer Covid-19 vaccine at a Los Angeles County mobile vaccination clinic in May, 2012. (Photo: AFP)

Earlier on Friday, the vaccine makers said their shot showed 90.7% efficacy against the coronavirus in a clinical trial of children 5 to 11 years old.

The details were in briefing documents published ahead of a meeting of a panel of outside experts scheduled to vote on Tuesday whether to recommend the FDA authorize the shots for the young age group.

If the FDA authorizes the Pfizer/BioNTech immunization for children 5 to 11 years old, it would be the first COVID-19 vaccine for the age group and shots could be available in the United States in early November.

Both the Pfizer/BioNTech and Moderna vaccines have been linked to rare cases of heart inflammation called myocarditis, especially in young men.