III.

Anthrax in Humans

In humans, the disease can appear in three forms: cutaneous, inhalation, and gastrointestinal. The cutaneous, or external form, primarily involves the skin and is contracted mainly by those who handle contaminated hides, wool, or carcasses. The bacteria enter through a cut or other opening in the skin, and a dark, itchy bump that resembles an insect bite appears. The bump then develops into an open sore with a black area in the center. The cutaneous form of anthrax can be treated with antimicrobial drugs. Death results in about 20 percent of untreated cases. Veterinarians, mill workers, laboratory researchers, and other people at risk of exposure to anthrax are generally vaccinated against the disease.

Humans contract internal forms of anthrax by inhaling anthrax spores or by eating contaminated meat. People who work with animal hair and wool are most likely to inhale the spores, especially in areas where anthrax occurs in animals. Symptoms of inhaled anthrax initially resemble those of a cold or the flu—general aches and pains, fever, fatigue, cough, and mild chest pain. Inhaled anthrax is fatal unless the infected person has been vaccinated or antibiotics are administered soon after inhalation. Ciprofloxacin, penicillin, and other antibiotics are effective treatments, except in rapidly progressing cases.

The gastrointestinal form of anthrax results from eating contaminated meat. Its symptoms are nausea, vomiting, abdominal pain, and severe diarrhea. The disease can be fatal in 20 percent to 60 percent of cases.