In the world of European medical research, few names carry more clout and prestige than the Institut Pasteur. In 1983, the French non-profit discovered HIV, and three years later found another strain of the disease. It has posted groundbreaking research in the study of diseases from yellow fever to tetanus to diphtheria. In all, its scientists have netted numerous Nobel Prizes, one of which came in 2008.

Now it’s in the news for something equally remarkable — but for a very different reason.

Days ago, the Paris institute announced that it lost more than 2,300 vials of SARS, a disease that killed more than 770 people and infected 8,000 more a decade ago, according to the Center for Disease Control and Prevention.

A routine inventory turned up the disappearance of the tubes. The institute suspects they’ve been missing since January, and as of Wednesday morning, no one knows what happened to them.

When scientists realized the vials had gone missing, they called France’s drug and health safety agency to see if it would have any more luck. It didn’t, reports the Local. Last week, the agency looked for the 2,300 missing vials in what the Institute calls an “in-depth” investigation at an unnamed lab.

But don’t worry, Pasteur says. “The tubes concerned have no infectious potential,” its statement said. “Independent experts referred by health authorities have qualified the risk as ‘nil.’”

Scientists dismissed the possibility that someone could put the virus to nefarious use.

“We knew from the beginning that the samples were not infectious, as the independent experts confirmed,” said Christian Brechot, Pasteur’s president, in an interview. He added that a malfunctioning freezer door would have killed the virus.

“[But] losing the samples is an unacceptable mistake,” he said. “We took a decision to inform the public. We want to be perfectly transparent. It is the first time that the institute has lost samples in this manner.”

Nonetheless, the disappearance of a deadly respiratory virus isn’t the sort of thing one shrugs off. The disease ripped through China in 2003 and hopped to Taiwan and Singapore, where dozens more died before it was stamped out.

It’s anyone’s guess what happened to the missing vials. “The theory of human error is the most probable, but we are not ruling anything out,” Bréchot said.