Smallpox

Diagnosis

If a smallpox outbreak happened today, most health care providers probably wouldn't recognize the virus in its early stages. This would allow the smallpox virus to spread.

Even one case of smallpox would be a public health emergency. The Centers for Disease Control and Prevention uses special labs to test tissue samples for smallpox. This test can tell for sure if a person has the virus.

Treatment

If someone were infected with smallpox, new antiviral medications may be used.

• Tecovirimat (Tpoxx). The U.S. Food and Drug Administration (FDA) approved this drug for use in the U.S. in 2018. Research found that it worked in animals and in lab tests. However, it hasn't been tested in people who are sick with smallpox. So it's not known if it's an effective drug option. A study tested it in healthy people and found it to be safe.
• Brincidofovir (Tembexa). The FDA approved this drug in 2021 for use in the U.S. Like tecovirimat, researchers tested brincidofovir in animals and in labs. Research hasn't tested it in people who have smallpox. It has been safely given to healthy people and people with other viruses.

It's unknown if these drugs work in a person with smallpox. Research continues to study other antiviral drugs to treat smallpox.