Thimerosal preservative history: which is accurate?

Thimerosal preservative history: which is accurate?

• A. A preservative previously used in some vaccines and not in most vaccines given to children today
• B. A preservative used in vaccines in large quantities
• C. A toxin found in vaccines
• D. A type of antibody

Answer: (A)

Thimerosal is a mercury-containing preservative that was used to prevent contamination in multi-dose vaccine vials. Historically, it was included in some vaccines, especially those given in multiple doses to children, to extend shelf life and reduce the risk of bacterial or fungal growth. Public health actions led to removing or reducing thimerosal from most vaccines routinely given to children, so today the vast majority of pediatric vaccines are thimerosal-free or contain only trace amounts. This makes the statement that it was used in the past and is not used in most vaccines given to children today the best description. It is not a toxin in the sense of being an added toxin at harmful doses, nor is it an antibody, and it wasn’t used in large quantities in vaccines administered to children.

Thimerosal is a mercury-containing preservative that was used to prevent contamination in multi-dose vaccine vials. Historically, it was included in some vaccines, especially those given in multiple doses to children, to extend shelf life and reduce the risk of bacterial or fungal growth. Public health actions led to removing or reducing thimerosal from most vaccines routinely given to children, so today the vast majority of pediatric vaccines are thimerosal-free or contain only trace amounts. This makes the statement that it was used in the past and is not used in most vaccines given to children today the best description. It is not a toxin in the sense of being an added toxin at harmful doses, nor is it an antibody, and it wasn’t used in large quantities in vaccines administered to children.