Flu vaccine has begun arriving in Maine, allowing doctors, health clinics and drug stores to start immunizing against the virus a couple of months before the season kicks into high gear.

Dr. Sheila Pinette, director of the Maine Center for Disease Control and Prevention, said officials are advising everyone to get immunized, except for those with an allergy to eggs or a previous severe reaction to flu vaccine.

Those at highest risk for the flu — children from six months to 18 years old, pregnant women, people with respiratory diseases and those over 65 — should definitely be immunized, but Pinette said medical officials recommend vaccinations for everyone as a way of preventing viruses from spreading.

The vaccine immunizes against five types of flu, she said, including H1N1, which circulated widely a couple of years ago and for which vaccine was in short supply for part of the 2009-2010 flu season. The vaccine formulation is the same as last year’s, she said.

Pinette noted that those who were vaccinated last year or who caught the flu during the last season should get vaccinated again because the immunity won’t carry over into the new season.

Flu season starts in the fall and is at its height from November through February, she said.

The state provides vaccine to nursing homes and their employees, to clinics serving under- or uninsured people, and to tribal and municipal health centers.

Most pharmacies and doctors’ offices also offer vaccinations.