Oct 26 (Reuters) - An expert panel on Tuesday will vote on whether to recommend the U.S. Food and Drug Administration authorize the Pfizer Inc (PFE.N) and BioNTech COVID-19 vaccine for children ages 5 to 11. An authorization for that age group would be would be an important regulatory step toward reaching about 28 million children for inoculation, most of them back in school for in-person learning.The FDA need not follow the advice of its outside experts, but usually does. The companies have said their vaccine showed 90.7% efficacy against the coronavirus in a clinical trial of children aged 5 to 11. read more While children become seriously ill or die far less often than adults from COVID-19, some develop complications, and cases in unvaccinated kids have risen due to the easily transmitted Delta variant of the coronavirus. The age group is "far from being spared from the harm of COVID-19," with the virus now one of the top-10 causes of deaths in American children, FDA official Peter Marks told the panel. He said there had been close to 100 deaths in that age group so far, and 1.9 million infections. Outbreaks also have caused school closures and disrupted the education and socialization of children, he said. Inoculating the age group could speed the pace of immunization in the United States, where the percentage of fully vaccinated people has fallen behind countries like the UK and France. The U.S. vaccination rate of 12- to 15-year-olds has lagged behind other age groups at roughly 47%. "Vaccinating children has other large societal benefits. For example, children likely play an important role in transmission and vaccinating children can help reach herd immunity," said William Gruber, a top vaccine scientist at Pfizer. FDA staff, in documents posted ahead of the meeting, said the likely vaccine benefits in that age group clearly outweigh the potential harms, including the rare risk of heart inflammation. Only a few other countries, including China, Cuba and the United Arab Emirates, have cleared COVID-19 vaccines for children in this age group and younger. The World Health Organization since May has been urging rich countries to reconsider plans to vaccinate children and instead donate COVID-19 shots to the COVAX program for distribution to poorer countries. read more The advisers are expected to pay close attention to the rate of a heart inflammation called myocarditis that have been linked to both the Pfizer/BioNTech and Moderna (MRNA.O) vaccines, particularly in young men. Pfizer and BioNTech are seeking clearance for a lower, 10-microgram dose of the vaccine in children, versus 30 micrograms for everyone over the age of 12. The shot has been authorized for ages 12-15 since May and cleared for everyone over 16 since December. Once the FDA authorizes the vaccine for younger children, an advisory panel to the U.S. Centers for Disease Control and Prevention will make a recommendation on the administration of the vaccine. The CDC director will make the final call. Top U.S. infectious disease expert Dr. Anthony Fauci said on Sunday it was likely the vaccine will be available to children in the first week or two of November. read more If the number of myocarditis cases in the younger age group turns out to be similar to that in 12- to 15-year-olds, the hospitalizations prevented for COVID-19 would outnumber those prevented for myocarditis in most scenarios analyzed, FDA staff reviewers said. Pediatric vaccinations are an important public health tool to prevent infectious diseases, even ones that do not cause high rates of mortality or hospitalization for children.