4 - Biological Agents, Effects, Treatment, and Differential Diagnosis

Abstract

This chapter discusses the various biological agents and their effects and treatments. The chapter also reviews the differential diagnosis for diseases such as anthrax, botulism, intoxication, plague, and smallpox. The causative agent of anthrax is Bacillus anthracis ( B. anthracis ), which is a sporulating gram-positive rod. There are three forms of anthrax: the inhalational anthrax—from inhalation of the aerosolized anthrax spores; the gastrointestinal anthrax—from eating food contaminated with the bacterium; and the cutaneous anthrax—from skin contact with an item contaminated with anthrax spores. Because of the urgent need to begin therapy, an initial diagnosis of anthrax should be made clinically. Definitive diagnosis can be made by isolating B. anthracis from a culture of blood. Anthrax vaccination is not recommended for the general public. The post-exposure prophylaxis (PEP) against inhalational anthrax is accomplished with ciprofloxacin 500 mg. The exposed individuals can receive three doses of vaccine (at 0, 14, and 28 days), enabling a shortened 30-day course of antimicrobials.