New, Safer Smallpox Vaccine Stockpiled

The U.S. government has begun to stockpile a new version of the smallpox vaccine that is designed to close a gap that left millions vulnerable to a bioterror attack. Denmark-based Bavarian Nordic’s Imvamune is made with modified vaccinia ankara, a safer alternative to the cowpox vaccines that have been used for generations. According to officials at Bavarian Nordic, the first shipments arrived in the U.S. Strategic National Stockpile in mid-May, which was within hours of a World Health Organization ceremony marking eradication of the disease.

While natural transmission of smallpox has ceased, the virus lives in freezers at the Centers for Disease Control and Prevention in Atlanta and, possibly, in Russia, where Soviet scientists are believed to have created tons of weaponized smallpox. The U.S. government started stockpiling the vaccine a decade ago after the breakup of the Soviet Union and the rise of global terrorism. “In June 2001, we had 12 million doses of smallpox vaccine for a population of 280 million,” says Randall Larsen, CEO of the nonprofit Weapons of Mass Destruction Center. Today, he says, the national stockpile contains 300 million doses of standard smallpox vaccine.