Only two locations in the world have these virus samples. They’re secured at the Centers for Disease Control and Prevention (CDC) in Atlanta and the State Research Center of Virology and Biotechnology (VECTOR Institute) in Russia.

Since smallpox no longer occurs naturally, public health officials are only concerned about it spreading as a result of biological warfare. There hasn’t been any immediate threat of terrorists using smallpox as a weapon. But scientists are prepared to respond if someone weaponized smallpox. The CDC has created enough smallpox vaccine to protect everyone in the United States if the virus does resurface.

https://my.clevelandclinic.org/health/diseases/10855-smallpox