Is smallpox still a threat?

Smallpox, a disease that killed an estimated 500 million people in the 20th century alone, is the only human disease to be eradicated. However, a new report, "Future State of Smallpox Medical Countermeasures," from the National Academies of Science, Engineering, and Medicine (NASEM) argues that the U.S. and the global community should prepare for smallpox to make a return.

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