SAN DIEGO -- Local parents looking to have their children vaccinated against the swine flu at school might not have that option, 10News reported.

Earlier this summer, San Diego County health officials said they sent survey letters to all school districts in the county. So far, of the county's 42 districts, only 25 -- including San Diego Unified -- have agreed to serve as vaccination sites.

Health officials said a handful of the districts have refused to serve as vaccination sites, and several other districts have lingering concerns.

Deputy Health Officer Dr. Dean Sidelinger said the concerns range from "having enough space to liability issues, to having a big enough need -- students in some areas have better access to medical providers."

The names of the districts on the fence have not been released, and Sidelinger said, "It wouldn't be fair because they've shown interest in talking. We're still working with their concerns and hoping they will agree to sign up."

Sidelinger said the school districts are only one part of a comprehensive campaign. He said parents' first option should be their own doctor's office.

"Others will get it through public health centers and mass vaccination clinics near their schools," said Sidelinger.

Vaccinations are expected to being in schools in mid- to late November.