LONG forgotten vials of smallpox left in a cardboard box have been found by a government scientist at a research centre near Washington, officials say.
The BBC reports the virus, believed dead, was located in six freeze-dried and sealed vials, according to the Centers for Disease Control and Prevention (CDC).
It is said to be the first time unaccounted-for smallpox has been discovered in the US.
The disease was officially declared eradicated in the 1980s.
"The vials appear to date from the 1950s. Upon discovery, the vials were immediately secured in a CDC-registered select agent containment laboratory in Bethesda, [Maryland]," according to a CDC statement.
"There is no evidence that any of the vials labelled variola has been breached, and onsite biosafety personnel have not identified any infectious exposure risk to lab workers or the public," the statement added.
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