ACAM2000 is an approved and used vaccine in the United States for smallpox and mpox prevention

Yes, the ACAM2000 vaccine is used in the United States. According to the search results, ACAM2000 is a second-generation smallpox vaccine approved by the US FDA and is part of the United States Strategic National Stockpile (SNS). It is used for active immunization against smallpox disease in persons determined to be at high risk for smallpox infection.
Additionally, the vaccine has been approved for mpox (monkeypox) prevention in the United States, as stated in the search results. The US Department of Defense started utilizing ACAM2000 in 2007, and it is manufactured by Emergent Biosolutions under a contract with the US Centers for Disease Control and Prevention (CDC).
The vaccine is administered using a bifurcated stainless steel needle, and precautions include screening before injection, as well as avoiding administration to immunocompromised or pregnant individuals due to the risk of pericarditis and myocarditis.
Overall, ACAM2000 is an approved and used vaccine in the United States for smallpox and mpox prevention, particularly for high-risk individuals.

Follow up
How does ACAM2000 compare to other smallpox vaccines in terms of efficacy and side effects?
What are the contraindications and precautions for administering ACAM2000 to individuals with pre-existing medical conditions?
What are the storage and handling requirements for ACAM2000, and how are they managed within the Strategic National Stockpile?

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2880337/
https://www.cdc.gov/smallpox/clinicians/vaccines.html
https://search.brave.com/search?q=Is+the+ACAM200+vaccine+used+in+the+U.S.&source=web&summary=1&summary_og=67413911439a414c42c81e
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