Six vials of potentially deadly smallpox virus have been discovered in a place they shouldn’t have been — an unused corner of a storage room at a Food and Drug Administration laboratory in Maryland, federal health officials said Tuesday.
It's the second lab lapse discovered in a month at federal facilities, though this mistake actually happened decades ago, experts emphasized. In June, more than 80 employees at a Centers for Disease Control laboratory were exposed to airborne anthrax bacteria in an embarrassing blunder.
But the new situation is different. The vials labeled variola, commonly known as smallpox, were discovered July 1 on the campus of the National Institutes of Health in Bethesda, by surprised employees preparing for an upcoming move, according to the CDC. NIH staff immediately notified the CDC's Divison of Select Agents and Toxins, or DSAT.
Tests confirmed the samples contained smallpox DNA. On Monday, they were safely transferred to the CDC’s high-containment laboratory in Atlanta.
The vials weren’t breached and biosafety personnel detected no risk of exposure to lab workers or the general public, CDC spokesman Tom Skinner said in a statement. Further tests that can take up to two weeks will determine whether the samples are viable, meaning they can grow in tissue culture, with the potential to spread.
The virus samples may have been in the storage unit since the laboratory was transferred from NIH to FDA in 1972, along with the responsibility for regulating biologic products. They appear to date from the 1950s, officials said.
Lab officials handled the situation appropriately, said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, who called the incident "a reminder to look at every freezer you have now just in case."
Still, the finding raises questions about why the vials were there at all, when international agreement stipulates that there are only two sites approved as repositories for smallpox samples: the CDC’s secure BSL-4 lab in Atlanta and the State Research Centre of Virology and Biotechnology (VECTOR) in Novosibirsk, Russia. The World Health Organization oversees these smallpox facilities and conducts regular reviews to certify safety.
Smallpox has been eradicated worldwide since 1980, but health experts worry about any potential exposure in a population where people born after that time have no immunity to the potentially deadly disease. In the aftermath of the 2001 U.S. terror attacks, there is “heightened concern that the variola virus might be used as an agent of bioterrorism,” the CDC says on its website.
Smallpox was responsible for between 300 million and 500 million deaths in the 20th century. The last case of smallpox in the U.S. occurred in 1949; the last naturally occurring case in the world occurred in Somalia in 1977, the CDC said.
CDC officials notified the World Health Organization about the discovery and invited the agency to participate in an investigation. If the samples are viable, WHO will be invited to witness the destruction of the vials, the approved procedure when samples are found outside approved labs.