Notice to Readers: Update: Expanded Availability of
Thimerosal Preservative-Free Hepatitis B Vaccine
Thimerosal, a mercury-based compound, is no longer used as a preservative in
any of the pediatric hepatitis B vaccines licensed in the United States. On March 28,
2000, SmithKline Beecham Biologicals (Rixensart, Belgium)* received approval from
the Food and Drug Administration of a supplement to its hepatitis B license to include
the manufacture of single-antigen, preservative-free hepatitis B vaccine
(Engerix-B, pediatric/adolescent); distribution of this product has begun. A
single-antigen, preservative-free hepatitis B vaccine (Recombivax HB, pediatric) from Merck
Vaccine Division (West Point, Pennsylvania) had earlier received similar approval
(1). A preservative-free Haemophilusinfluenzae type b (Hib)/hepatitis B combination
vaccine (Comvax) from Merck Vaccine Division also is available. An adequate supply
of preservative-free hepatitis B vaccine is available for all infant and
childhood vaccinations. Thimerosal preservative-containing hepatitis B vaccines may continue
to be used for vaccination of adolescents and adults as recommended
(2).
Some vaccines that do not use thimerosal as a preservative may have
trace amounts of thimerosal introduced during the manufacturing process. The amount
of thimerosal in the new pediatric/adolescent formulation of Engerix-B (<1 µg
of thimerosal/0.5 mL dose of vaccine) has been reduced by more than 96%
(3).
Universal vaccination of infants is the central focus of hepatitis B
prevention efforts, and initiation of the hepatitis B vaccine series at birth is safe and effective
(4). Many hospitals that had provided routine hepatitis B vaccination to all infants at
birth before the July 1999 joint American Academy of Physicians/Public Health
Service statement on thimerosal in vaccines discontinued this practice because of
concerns about thimerosal (1). Some of these hospitals did not resume routine vaccination
at birth even after hepatitis B vaccines that do not contain thimerosal as a
preservative became available (CDC, unpublished data, 2000). Preservative-free hepatitis B
vaccines are now widely available, and efforts should be made to reintroduce routine hepatitis
B vaccination policies for all newborn infants in hospitals in which these policies
and
practices have been discontinued.
References
CDC. Availability of hepatitis B vaccine that does not contain thimerosal as a
preservative. MMWR 1999;48:780--2.
CDC. Implementation guidance for immunization grantees during the transition period
to vaccines without thimerosal, CDC, July 14, 1999. Available at
http://www.cdc.gov/nip/news/thimerosal-guidance.htm. Accessed July 14, 2000.
CDC. Summary of the joint statement on thimerosal in vaccines. MMWR 2000;49:622,631.
Advisory Committee on Immunization Practices. Hepatitis B virus: a comprehensive
strategy for eliminating transmission in the United States through universal childhood
vaccination. MMWR 1991;40(no. RR-13).
* References to sites of non-CDC organizations on the World-Wide Web are provided as
a service to MMWR readers and do not constitute or imply endorsement of these
organizations or their programs by CDC or the U.S. Department of Health and Human Services. CDC is
not responsible for the content of pages found at these sites.
Disclaimer
All MMWR HTML versions of articles are electronic conversions from ASCII text
into HTML. This conversion may have resulted in character translation or format errors in the HTML version.
Users should not rely on this HTML document, but are referred to the electronic PDF version and/or
the original MMWR paper copy for the official text, figures, and tables.
An original paper copy of this issue can be obtained from the Superintendent of Documents,
U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800.
Contact GPO for current prices.
**Questions or messages regarding errors in formatting should be addressed to
mmwrq@cdc.gov.
