Health officials say a Nassau County adult diagnosed with swine flu has died.

The individual was over the age of 55 and had serious underlying medical conditions. It is the third reported death of a swine flu patient in Nassau County this year.

State health officials say the first H1N1 vaccinations on Long Island are expected to start Tuesday. Anybody 10 and older will get one dose of the vaccine, while younger children need to get two doses three weeks apart.

Long Island residents can get the vaccine for free at special clinics set up in Nassau and Suffolk, though most hospitals and private doctors will charge a small fee.

This story was written with Associated Press wire reports