An investigation into the possible discovery of a live virus from smallpox was officially ended Monday, when federal health officials announced that samples discovered in a laboratory had not been in an improper condition when they disappeared.
The Centers for Disease Control and Prevention (CDC) launched an investigation in February after it was discovered that samples of four vials of ancient smallpox samples were missing. Over the course of the investigation, the agency believed the vials contained a virus that infected humans and could kill them with its symptoms.
But on Monday the CDC said that the virus shown in pictures released to the media was a reconstructed sample of the medieval plague virus that had already passed through the bacterium, now known as Yersinia pestis. In a statement, the CDC said the virus in question was determined to have “no potential to cause disease in humans or in animals, and is not a reason for concern.”
“We are providing the news media and public with this information today because it is important for everyone to understand that these samples did not contain a virus that could spread to humans or animals or cause disease,” Richard Wenzel, director of CDC’s Division of Emerging and Zoonotic Infectious Diseases, said in a statement. “We assure the public that our investigational research labs at the CDC are safe.”
In February, CDC officials announced that their investigation had concluded and that there was no evidence of anyone having been exposed to the potentially dangerous virus. But in an update on Monday, CDC officials explained that they had “not fully assessed the implications” of the finding and that they were “still learning more” about the rest of the situation.
CDC officials have since said they will stop doing research on smallpox, a disease that is thought to have killed 50 million people from the mid-14th century until its destruction in 1980.
In spite of the CDC’s announcement, there has still been a surge in the smallpox industry over the past few weeks. Last week, customs officials in Hanukkah. Alaska seized the first shipment of smallpox vaccines in two years.