Thimerosal and 2011–2012 Seasonal Flu Vaccines

Was just reading up on the CDC web site a Q&A section about the Thimerosal and 2011–2012 Seasonal Flu Vaccines...So I thought I post the article.

What is thimerosal?

Thimerosal is a mercury–based preservative that has been used for decades in the United States in multi–dose vials (vials containing more than one dose) of some vaccines to prevent the growth of germs, bacteria and fungi, that can contaminate them.

What are preservatives and why are they sometimes used in vaccines?

Preservatives have been used in vaccines for more than 70 years and are added to vaccines to prevent the growth of bacteria or fungi that could possibly make the vaccine in multi–dose vials unsafe. This may occur when a syringe needle enters a vial as a vaccine is being prepared for administration. Contamination by germs in a vaccine could cause serious infections.

Do the 2011–2012 seasonal flu vaccines contain thimerosal?

The Food and Drug Administration (FDA) has approved several formulations of the seasonal flu vaccine, including multi–dose vials and single–dose units. (See Table of Approved Influenza Vaccines for the U.S. 2011–2012 Season.) Since seasonal influenza vaccine is produced in large quantities for annual immunization campaigns, some of the vaccine is produced in multi–dose vials, and contains thimerosal to safeguard against possible contamination of the vial once it is opened.
The single–dose units are made without thimerosal as a preservative because they are intended to be opened and used only once. Additionally, the live–attenuated version of the vaccine (the nasal spray vaccine), is produced in single–dose units and does not contain thimerosal.

Is thimerosal being used in other vaccines?

Since 2001, no new vaccine licensed by FDA for use in children has contained thimerosal as a preservative, and all vaccines routinely recommended by CDC for children younger than 6 years of age have been thimerosal–free, or contain only trace amounts of thimerosal, except for multi–dose formulations of influenza vaccine. The most recent and rigorous scientific research does not support the argument that thimerosal–containing vaccines are harmful. However, CDC and FDA continually evaluate new scientific information about the safety of vaccines.

To read more....please visit the web site at....
http://www.cdc.gov/flu/protect/vaccine/thimerosal.htm