The Public Health Response and Epidemiologic Investigation Related to the Opening of a Bacillus anthracis–Containing Envelope, Capitol Hill, Washington, D.C.

摘要

On October 15, 2001, a U.S. Senate staff member opened an envelope containing Bacillus anthracisspores. Chemoprophylaxis was promptly initiated and nasal swabs obtained for all persons in the immedi-ate area. An epidemiologic investigation was conducted to define exposure areas and identify personswho should receive prolonged chemoprophylaxis, based on their exposure risk. Persons immediatelyexposed to B. anthracis spores were interviewed; records were reviewed to identify additional persons inthis area. Persons with positive nasal swabs had repeat swabs and serial serologic evaluation to measureantibodies to B. anthracis protective antigen (anti-PA). A total of 625 persons were identified as requiringprolonged chemoprophylaxis; 28 had positive nasal swabs. Repeat nasal swabs were negative at 7 days;none had developed anti-PA antibodies by 42 days after exposure. Early nasal swab testing is a usefulepidemiologic tool to assess risk of exposure to aerosolized B. anthracis. Early, wide chemoprophylaxismay have averted an outbreak of anthrax in this population