Pinellas County schools began administering vaccinations for the H1N1 virus, or swine flu, on Monday, but some students who thought they were all ready to get a shot didn't get one.

That's because their parents had not signed an updated online consent form that was posted on the district's website Friday, said Andrea Zahn, spokeswoman for the school district. Zahn could not immediately say how many students did not get the vaccine on Monday because of the last-minute change.

The new form was posted because the Pinellas County Health Department, which is collaborating with the district on the program, realized that it might not have enough injectable vaccinations without the preservative Thimerosal on hand.

The new consent form asks parents to authorize that their children can receive a nasal mist version of the vaccine that is preservative free. Parents who chose on the original questionnaire that their child could take either version of the vaccine do not need to fill out the new form. Children with certain chronic diseases cannot take the nasal mist.

Maggie Hall, a spokeswoman for the health department, blamed national shortages of the preservative-free vaccine.

The program in Pinellas schools is expected to over in two weeks, before the Thanksgiving holiday break.
More information about the vaccine is available on the district's Web site at www.pcsb.org. Parents who have questions should call the Health Department at (727) 824-6964.

- Luis Perez, Times staff writer