On April 5, 2002, CDC reported a case of suspected cutaneous anthrax in a worker at laboratory A who had been processing environmental samples for Bacillus anthracis in support of CDC investigations of the 2001 bioterrorist attacks in the United States.1 Since the initial report, the worker had serial serology performed at the CDC laboratory. A greater than fourfold rise from baseline in the concentration of immunoglobulin G to protective antigen was demonstrated. The peak antibody level was observed 7-8 weeks after the onset of symptoms, and the time course and levels of detectable antibodies were consistent with those seen in other cases of cutaneous anthrax. On the basis of case definitions developed during the recent investigation, these additional findings confirm this as a case of cutaneous anthrax.2 This case brings the number of anthrax cases identified in the United States since October 3, 2001, to 23, including 11 inhalation and 12 cutaneous (eight confirmed and four suspected). This is the first laboratory-acquired case of anthrax associated with the recent investigation.
The epidemiologic and environmental investigation of this case indicated that the probable source of exposure was the surface of vials containing B. anthracis isolates that the worker had placed in a freezer. The storage vials had been sprayed with 70% isopropyl alcohol, which is not sporicidal, instead of a bleach solution because bleach had caused labels to become dislodged. The worker did not wear gloves when handling the vials. A culture of the vial tops performed at laboratory A tested positive for B. anthracis. The vial top specimen was confirmed positive for B. anthracis at CDC. Multiple-locus variable-number tandem repeat analysis found this isolate to be indistinguishable from the culture of the worker's clinical specimen. This case underscores the importance of safe laboratory procedures and anthrax vaccination for workers routinely handling B. anthracis isolates.3
EH Page, MD, KF Martinez, MSEE, TA Seitz, MPH, BP Bernard, MD, AL Tepper, PhD, Div of Surveillance, Hazard Evaluations, and Field Studies, National Institute for Occupational Safety and Health; RS Weyant, PhD, Office of Health and Safety; CP Quinn, PhD, NE Rosenstein, MD, BA Perkins, MD, T Popovic, PhD, Div of Bacterial and Mycotic Diseases; HT Holmes, PhD, Div of Healthcare Quality Promotion, National Center for Infectious Diseases; CW Shepard, MD, EIS Officer, CDC.
Public Health Dispatch: Update: Cutaneous Anthrax in a Laboratory Worker—Texas, 2002. JAMA. 2002;288(4):444. doi:10.1001/jama.288.4.444-JWR0724-2-1