Vaccine Lab Worker Cleaning Freezer Makes Disturbing Find

What started out as a routine chore in a Pennsylvania vaccine research lab this week has ended up attracting the attention of the FBI and CDC. According to an alert sent out Tuesday by the Department of Homeland Security, a worker at a Merck facility near Philly, in Montgomery County, was cleaning out a lab freezer on Monday when he or she came across 15 "questionable vials," five of which were labeled "smallpox," reports Yahoo News. The other 10 vials were labeled "vaccinia." The facility was locked down after the worker reported the find, and the vials—whose contents appeared to be "intact," per a CDC spokesperson—were secured.

"There is no indication that anyone has been exposed to the small number of frozen vials," the CDC rep noted, adding that the worker was wearing gloves and a face mask while cleaning out the freezer. Live Science notes there are only two labs on the planet legally allowed to hold samples of the deadly variola virus that causes smallpox, a disease declared eradicated in 1980 by the World Health Organization after a worldwide vaccination push: one in a CDC facility in Atlanta, the other in a Russian bioweapons lab. Although some scientists have argued that all samples of the virus worldwide should be destroyed, lest they somehow find their way into a mostly unvaccinated population, others say we should keep a few around in case an outbreak occurs and we need to create a new vaccine.

Dr. Thersa Sweet of Drexel University's School of Public Health is baffled as to how these vials could have remained at the lab. "Frankly, I'm surprised this would happen at someplace like Merck," she tells WPVI. "All of the vials of smallpox that were out in virologists' freezers were supposed to be disposed of once the disease was considered eradicated." Still, a Rutgers University chemistry professor tells the Philadelphia Inquirer that, despite how deadly smallpox is, the worker who stumbled upon the vials faces a small-to-none risk of being infected, and everyone else has even less to worry about. "For the general public there is no basis for being worried, even a small amount," says Richard Ebright. The lockdown at the Merck facility has since been lifted. (More smallpox stories.)