Chicago - Seasonal flu vaccinations are safe for children from six to 23 months of age, the largest study of the question to date has reported.
"This is really good news for both doctors and parents who want to protect young children from influenza and complications of this nasty illness," said Dr Simon Hambidge of Kaiser Permanente Colorado, chief author of the report.
Government health experts have recommended vaccinations against seasonal influenza yearly for children from six to 23 months since 2004, based on preliminary safety data.
Such vaccinations had been going on before then since children in that age group are particularly prone to complications once they come down with the illness.
The new study looked at more than 45 000 children in eight United States health-care plans who were vaccinated between 1991 and 2003. As a group they had received more than 69 000 vaccinations.
The study found very few post-vaccination problems that required a doctor's intervention, "none of which were serious".
"While our findings offer reassurance regarding the safety of the vaccine in the youngest children, large safety studies of influenza vaccine in children in the newly recommended age group of children three to five years old are needed," said the study, which was published the Journal of the American Medical Association.
"Our study, the largest safety study of trivalent inactivated influenza vaccine in children aged six to 23 months, adds to prior evidence that influenza vaccine is safe in infants and young children," it said.