Children and teens on aspirin therapy, women in the second or third trimester of pregnancy, and nursing home residents should also get a flu shot. Even healthy people who could expose high-risk persons to the flu should get a vaccine each year. This includes health care workers and family members. Flu shots are given at most public health departments and doctors' offices. It is best to get a flu shot in the fall, before influenza season begins.
Flu vaccine contains no live virus and only parts of killed viruses.
The vaccine boosts the immune response against influenza. There may be some soreness, redness or swelling where the shot is given. Other possible mild side effects include a headache and low-grade fever for a day after the vaccination. The risks from the disease are much greater than the risks from the vaccine. The best way to prevent the flu is to get a flu shot each year.