ACAM2000

A detailed overview of the ACAM2000 smallpox vaccine

Overview

ACAM2000 is a live vaccinia virus vaccine used for the prevention of smallpox. It is a second-generation smallpox vaccine developed to replace the older Dryvax vaccine. ACAM2000 is produced by Sanofi Pasteur and was licensed by the FDA in 2007.

History

The development of ACAM2000 was initiated in response to the need for a safer and more effective smallpox vaccine. The original smallpox vaccine, Dryvax, was derived from calf lymph and had been in use since the 1970s. Due to concerns about the safety and availability of Dryvax, the U.S. government sought to develop a new vaccine. ACAM2000 was developed using modern cell culture techniques, specifically using the African green monkey kidney cell line, Vero cells.

Mechanism of Action

ACAM2000 contains live vaccinia virus, which is closely related to the variola virus that causes smallpox. When administered, the vaccine induces an immune response that provides protection against smallpox. The vaccinia virus in ACAM2000 replicates at the site of inoculation, leading to the formation of a localized lesion known as a "take." This process stimulates the body's immune system to produce antibodies and T cells that confer immunity to smallpox.

Administration

ACAM2000 is administered using a bifurcated needle, which is dipped into the vaccine solution and then used to prick the skin multiple times in a small area, usually on the upper arm. This method of administration is known as "scarification." A successful vaccination is indicated by the development of a pustular lesion at the site of inoculation within 6 to 8 days.

Safety and Side Effects

While ACAM2000 is generally safe, it can cause side effects, some of which can be serious. Common side effects include soreness at the injection site, fever, and swollen lymph nodes. More serious side effects can include myocarditis, pericarditis, and encephalitis. Due to these potential risks, ACAM2000 is primarily used for military personnel and laboratory workers who are at high risk of exposure to smallpox.

Current Use

ACAM2000 is part of the U.S. Strategic National Stockpile and is used to protect military personnel and certain civilian populations in the event of a smallpox outbreak. It is not available for general public use due to the eradication of smallpox and the associated risks of the vaccine.

Related pages

• Smallpox
• Vaccinia
• Vaccination
• Bioterrorism

Gallery

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  A bifurcated needle used for administering the ACAM2000 vaccine.