This article is more than 5 years old. Information may no longer be current.
CDC halts transfer of select agents within, outside agency labs
Click Here to Manage Email Alerts
As a result of two incidents related to unintentional exposure of highly pathogenic organisms, the CDC has issued a moratorium on the transfer of biological materials, inside or outside the agency, from biosafety level 3 or 4 laboratory facilities.
The moratorium will be in place until there has been a lab-by-lab assessment.
“These events should never have happened,” CDC Director Thomas Frieden, MD, MPH, said during a media briefing. “I’m disappointed that this happened, and frankly, I’m angry. We are, essentially, the reference laboratory for the world, so when something like this happens here, it is inexcusable.”
Thomas Frieden
The moratorium is the result of a review of an incident in June in which Bacillus anthracis samples that were supposed to be inactivated for research at a BSL-2 laboratory were not adequately prepared. The potentially infectious samples were moved and handled by researchers not adequately protected to handle live B. anthracis.
Frieden said that the process used to inactivate the anthrax spores was not the scientifically-derived and reviewed protocol established within the CDC to guarantee the anthrax spores were killed. Subsequent experiments showed that although it was not impossible that some live spores were transferred, it was extremely unlikely.
During its investigation, the CDC learned of another incident earlier in the year in which a culture of non-pathogenic avian influenza was cross-contaminated with the H5N1 strain of influenza and sent to a BSL-3 laboratory operated by the United States Department of Agriculture (USDA). This incident is still under review, although Frieden said that no personnel were at risk for the pathogenic influenza.
“This incident is the most distressing not because it’s more contagious, but because it took place about 6 weeks ago and I only learned about it 48 hours ago,” Frieden said. “Our influenza laboratory is a superb laboratory and the fact that it took so long to notify us is very troubling. This was unexpected and we will do a full investigation.”
Frieden also discussed an incident earlier this week in which vials of smallpox were found on the NIH campus. The CDC is in the process of investigating the vials and found that they did, in fact, contain smallpox DNA, and two vials have returned viable smallpox in culture. Investigators are analyzing the entire genetic sequence of the viable smallpox and are monitoring the other four vials. The vials will be destroyed when the research is complete.
In addition to the moratorium on the transfer of select agents, Frieden has implemented a number of steps to improve laboratory safety, including appointing Michael Bell, MD, to be director of laboratory safety for the CDC, as a single point of accountability to oversee implementation of the recommendations.
Michael Bell
Another step includes establishing a high-level working group reporting to the CDC director to accelerate improvements in laboratory safety and review and approve the transfer of biological materials outside of BSL-3 and BSL-4 laboratories on a lab-by-lab basis. They will also serve as the transition group for the single point of accountability on laboratory safety called for in the review of the potential anthrax exposure incident.
Frieden is also establishing an external advisory group for laboratory safety.
The CDC has taken several steps in response to these incidents, including initiating an investigation to determine how another avian influenza virus was contaminated by the H5N1 virus; reporting the incident to the USDA Animal and Plant Health Inspection Service; and establishing a review group to analyze the systems, procedures and personnel issues leading to these events and how to prevent future events.
It is also undertaking appropriate personnel action against individuals who contributed to or who were in a position to prevent the incidents.
“The culture of laboratory safety needs to improve,” Frieden said. “It’s very important to understand that mistakes are human and that’s why we have these safety protocols in place. There are lapses in laboratory procedures and that is a problem that is a symptom of a broader problem of laboratory safety.”
Perspective
Back to Top
D.A. Henderson, MD, MPH
It is surprising to learn this about CDC because its scientists have played a key role in defining procedures and protocols for laboratories working with the select agents. Also, I believe that several current and former CDC staff have themselves participated in licensure and inspection of such laboratories.
The discovery of smallpox specimens at NIH represents a wholly different phenomenon — something like what we called the Dagwood closet problem. As I understand it, the specimens were prepared in 1954 by freeze-drying, sealed in a vacuum, and stored in a cold room. There were specimens of other agents similarly prepared — all were in a box. I strongly suspect that these represented a diagnostic kit for use in virus laboratories for comparison with new isolates from patients. The 50s were very early days for tissue cell culture and the freeze-dry/vacuum technique and apparatus for virus preservation were comparatively new. Note that if someone were infected accidently by smallpox virus from the storage tube, the threat would be vastly different from possible escape of a pathogenic influenza virus. With smallpox, we have a virus which is far less contagious, but with a potentially high case-fatality rate. Containment of an outbreak of five to 20 cases would be readily dealt with. The smallpox threat rests with the potential of some entity producing the virus in quantity and in a form that could be aerosolized. An influenza escape has ominous implications for rapid, essentially uncontrollable spread.
Click Here to Manage Email Alerts