CDC TB lab resumes transfer of inactivated materials

The Centers for Disease Control and Prevention announced on Thursday that its Clinical Tuberculosis Laboratory resumed transfer of inactivated materials after an intensive review by the Laboratory Safety Improvement Working Group.

Following the review, CDC Director Tom Frieden lifted the moratorium on a specific type of material transfer for the tuberculosis (TB) lab. Labs that support direct patient care have received a priority review. The moratorium remains in place for the CDC's other biosafety level 3 (BSL-3) and BSL-4 laboratories, according to a CDC press release.

The BSL-3 TB lab uses a heat kill process to inactivate TB bacteria isolated from patients before sending it to a lower-level BSL-2 lab for genetic analysis. The lab submitted details of its material transfer plan to the internal working group. The plan includes safety procedures for each step of the TB inactivation process, as well as risk assessment, validation and rules for personal protective equipment to ensure the heat kill process was correctly conducted.

The lab was not one of the two labs involved in recent safety incidents, both of which remain closed.

On July 11, Frieden stopped the transfer of all biological materials from CDC laboratories in response to the safety incidents. No biological material may leave any BSL-3 and BSL-4 labs as part of the moratorium.

The internal working group is conducting a lab-by-lab review of safety procedures. The reviews focus on a demonstration that its protocols for key points are being used by appropriately trained individuals and the establishment of redundant controls.