WASHINGTON (AP) -- Giving injections to thousands of children -- even something as easy and safe as influenza vaccine -- is complicated. But there are resources to help schools plan flu-vaccine clinics.

"It's not just going from desk to desk and giving a little polio vaccine on a sugar cube," warned Dr. William Schaffner of Vanderbilt University, a vaccine specialist who advises the federal government.

Early planning is key, added Robert Pestronk of the National Association of County & City Health Officials.

His group offers sample letters to parents explaining the vaccination process and also case studies of different ways school systems have successfully performed flu vaccinations. The group even provides a checklist to help officials be sure they've remembered every detail.

Health professionals have to administer flu vaccine, and typically local health departments do the job.

First decision: which to offer, vaccination against regular winter flu, swine flu or both? Health officials believe that swine flu inoculation will require two shots, three weeks or so apart, whereas vaccination against regular winter flu requires a separate jab.

Regardless, no kid can be vaccinated in school unless a parent or guardian properly fills out a permission slip that includes questions about the child's health history. For example, people with severe egg allergies aren't supposed to get flu vaccine, and certain conditions require that people receive the flu shot instead of the nasal-spray version.

Have someone check the consent forms ahead of vaccination day because many parents miss questions or forget to sign them, warned Jennifer Johnson of the Knox County, Tenn., Health Department, which has offered in-school FluMist vaccination for four years.

Flu vaccine side effects are generally mild, such as a sore arm or some fever. But Schaffner warns that weird things can happen, too -- like the fact that adolescent girls sometimes faint when they get a shot. Health officials recommend observing children for 15 minutes after vaccination.

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