CDC places moratorium on hazardous biomaterial transfers

The U.S. Centers for Disease Control and Prevention announced a moratorium on Friday on the movement of biological materials from biosafety level 3 (BSL-3) and BSL-4 facilities.

The moratorium came after three safety incidents involving the potential exposure of lab employees to potentially deadly pathogens. In one incident, six forgotten vials of smallpox virus were found in a storage unit of the U.S. Food and Drug Administration. In mid-June, dozens of CDC employees were potentially exposed to anthrax bacteria, The Scientist reports.

In the other incident, CDC influenza lab personnel reported the inadvertent contamination of an avian influenza virus sample with highly pathogenic H5N1. The flu sample was shipped to a U.S. Department of Agriculture (USDA) facility.

Tom Frieden, the director of the CDC, said six weeks passed before the H5N1 contamination incident was reported to agency officials. He called the delay "troubling" and noted that no one was exposed to the flu virus, which has since been destroyed.

"These events should never have happened," Frieden said, according to The Scientist. "Fundamentally, what they reveal is totally unacceptable behavior."

Frieden said the incidents were a symptom of a broader issue of laboratory safety inside and outside the government. He said the CDC will work to reduce the number of select agents in government labs, downsize the workforce using the materials and increase security.

The moratorium on movement of materials from BSL-3 and BSL-4 will remain until an advisory committee can conduct a review.

"I'm just astonished that this could have happened here," Frieden said, according to The Scientist. "These are wake-up calls. These are events that tell us we have a problem. We're going to fix them."