Do you know what's in a flu shot?

Do all flu vaccines contain thimerosal?

No. Influenza vaccine is currently available both with thimerosal as a preservative and preservative-free. For the 2004-05 influenza season, it is likely that 6-8 million doses of inactivated influenza vaccine without thimerosal as a preservative will be available. This represents a substantial increase in the available amount of inactivated influenza vaccine without thimerosal as a preservative, compared with about 3.2 million doses that were available during the 2003-04 influenza season.

The removal of thimerosal as a preservative from influenza vaccine is a complicated process. The total amount of flu vaccine without thimerosal as a preservative will be increased as vaccine manufacturing capabilities are expanded. In the meantime, it is important to keep in mind that the benefits of influenza vaccination outweigh the theoretical risk, if any, for exposure to thimerosal. Each year, an average of about 36,000 people in the United States die from influenza, and 114,000 have to be admitted to the hospital as a result of influenza. People age 65 years and older, people of any age with chronic medical conditions, and very young children are more likely to get complications from influenza.