Clinical Manifestations and Pathology
In its principal animal hosts, anthrax may take one of three forms: (1) a peracute type (splenic apoplexy), where sudden death occurs almost simultaneously with the first symptoms; (2) an acute type characterized by an acute fever, usually followed by death after 2 to 12 days; and (3) a subacute type often followed by recovery.
Classical signs include fever, stupor, spasms, convulsions, intestinal disturbances, and respiratory or cardiac distress. Death follows septicemia and accompanying severe toxic manifestations. Characteristic enlargement of the spleen is reflected in the name of splenic fever.Anthrax in people may take the form of a malignant pustule (cutaneous anthrax), where the bacilli enter through the skin, producing a primary lesion developing into a characteristic area Ofinflammation surrounding a dark necrotic center; or it may take the form of the pulmonary or - less commonly - the intestinal type, which follows inhalation of dust containing anthrax spores, as has occurred in the woolen industries. Monkeys exposed to artificially generated aerosols of anthrax spores develop symptoms mimicking woolsorters’ disease. Postmortem findings include hemorrhages in the lung, hemorrhagic mediastinitis and lymphadenitis, and sometimes hemorrhagic meningitis.