Washington ? Flu-shot season begins next week, and this year marks the first time parents are being urged to get babies and toddlers vaccinated because influenza sends its tiniest patients to the hospital as often as it does the elderly.

But theres a catch: Unlike the one yearly shot most people need, the first-ever inoculation for young children requires two doses a month apart. So experts are urging parents not to delay that pediatrician visit, to be sure their children get both shots in time.

Theres plenty of flu vaccine this year, according to federal health officials who estimate 94 million doses will be shipped.

Still, it takes awhile to send vaccine to every doctors office and vaccination clinic. The government is calling for people at the highest risk of severe illness during flu season to be first in line in October and urging healthy people to wait until November to get their shots.

Recent research suggests children under age 2 are as likely to be hospitalized with flu complications such as pneumonia as are people over age 65 the age group long thought to be at highest risk. The CDC is working to confirm that, but meanwhile decided to encourage vaccinating children age 6 months to 2 years.

The vaccine cant be given to younger infants, whose family and caregivers are urged to get vaccinated themselves so they dont spread the virus to newborns.

While the elderly are at high risk of death from flu, hospitalizing babies usually saves them. But its traumatic and exposes babies to unnecessary antibiotics until doctors confirm they have viral flu, not a bacterial infection, says Dr. Leonard B. Weiner, pediatric infectious disease chief at the State University of New York, Syracuse. Germ-filled hospitals expose already weak babies to other infections.

The American Academy of Pediatrics encouraged pediatricians to stock vaccine for more babies than ever this fall.