Agents of Biologic and Chemical Warfare
Biologic and chemical agents have been weaponized to produce diseases. Many of these agents are not commonly encountered by clinicians or pathologists in their daily practices but have received greater attention as potential threats in recent years. Chemical warfare agents include nerve agents such as sarin, tabun, soman, and VX gas; vesicants such as sulfur mustard and nitrogen mustard; pulmonary agents such as phosgene and chlorine; and cyanides. Potential biologic warfare agents include smallpox, anthrax, plague, botulism, tularemia, Ebola hemorrhagic fever, Marburg hemorrhagic fever, Lassa fever, and Argentine hemorrhagic fever.
Part 1 Anthrax
Abida K. Haque
Anthrax, primarily a disease of herbivores, is a zoonotic disease due to infection with Bacillus anthracis. Exposure to the bacteria may result in cutaneous, gastrointestinal, or pulmonary disease. Pulmonary disease results from inhalation of infective spores and was particularly common in wool-sorters. Clinically, a severe respiratory distress develops, with shock and death within 24 to 48 hours of onset. Chest radiographs show a characteristic expansion of mediastinum.
The hallmark lesions of anthrax are edema and hemorrhage.
The lungs show extensive suppurative and hemorrhagic bronchopneumonia with abundant gram-positive rods measuring 1 to 1.25 × 3 to 5 μm.
The bacilli are described as “boxcar” or “bamboo rod.”
The mediastinum shows massive edema and enlarged hemorrhagic lymph nodes.