Epidemiologic investigations of bioterrorism-related anthrax, New Jersey, 2001

Abstract

At least four Bacillus anthracis-containing envelopes destined for New York City and Washington, D.C. were processed at the Trenton Processing and Distribution Center (PDC) on September 18 and October 9, 2001. When cutaneous anthrax was confirmed in a Trenton postal worker, the PDC was closed. Four cutaneous and two inhalational anthrax cases were identified. Five patients were hospitalized; none died. Four were PDC employees; the others handled or received mail processed there. Onset dates occurred in two clusters following envelope processing at the PDC. The attack rate among the 170 employees present when the B. anthracis-containing letters were sorted on October 9 was 1.2%. Of 137 PDC environmental samples, 57 (42%) were positive. Five (10%) of 50 local post offices each yielded one positive sample. Cutaneous or inhalational anthrax developed in four postal employees at a facility where B. anthracis-containing letters were processed. Cross-contaminated mail or equipment was the likely source of infection in two other case-patients with cutaneous anthrax.

Figure 1

Timeline of events during bioterrorism-related epidemic, New Jersey, September–October, 2001. Red box = l case-patient with onset of inhalational anthrax; blue box = l case-patient with onset of cutaneous anthrax.

Figure 2

Floor map of the Trenton Postal Distribution Center in Hamilton Township with locations of environmental samples taken October–November, 2001, and work stations of New Jersey case-patients on dates when letters containing Bacillus anthracis were sorted. Blue man = male, cutaneous anthrax; red woman = female, inhalational anthrax. *Machine mechanic worked throughout the mail-sorting area the night the letters containing B. anthracis destined for New York were sorted.