CDC distributing new smallpox vaccine

Old Dryvax supplies should be destroyed

The Centers for Disease Control and Prevention is distributing a new-generation smallpox vaccine, ACAM2000 (Acambis, Inc.; Cambridge, MA), to civilian laboratory personnel, the military, and state public health preparedness programs.

ACAM2000 is a live, vaccinia virus smallpox vaccine that was licensed for use in the United States by the Food and Drug Administration in August 2007. ACAM2000 will replace Dryvax® smallpox vaccine (Wyeth Pharmaceuticals Inc.; Marietta, PA) because of withdrawal of the Dryvax license. ACAM2000 is a live vaccinia virus derived from plaque purification cloning from Dryvax. The safety data available from the ACAM2000 clinical trials indicate a similar safety profile to Dryvax. Wyeth intends to withdraw the Dryvax license and asks that all remaining quantities of vaccine held by civilian and military users be quarantined by Feb. 29, 2008, for the purpose of destruction. This withdrawal is not necessitated by any safety, purity, or quality concerns with the product but rather is consistent with a contract agreement between CDC and Wyeth. All lots of Dryvax vaccine will expire on Feb. 29, 2008, and should not be used after that date.

According to the CDC, all Dryvax vaccine should be destroyed on site. Vaccine vials can be 1) dropped into the hospital sharps container and autoclaved; or 2) disposed of following the procedure for all other biohazard materials. In sites where medical waste is buried, soaking the medical waste in a 1:10 dilution of bleach for at least 10 minutes before disposal is advised. All programs that hold supplies of Dryvax vaccine must provide documentation of Dryvax vaccine destruction to the CDC Drug Service by March 31, 2008. These programs are advised to use the Dryvax vaccine destruction form. (Available at

CDC will continue to provide ACAM2000 smallpox vaccine to protect responders as part of state public health preparedness programs and civilian laboratory personnel who risk exposure to orthopoxviruses. Unlike Dryvax, ACAM2000 expires 18 months after release from the CDC Strategic National Stockpile. Requests for smallpox vaccine should be directed to the CDC Drug Service by e-mail ( or telephone [(404) 639-3670].