Plague Pneumonia.

Yersinia pestis is a gram-negative bacillus that can cause pneumonia if inhaled. Secondary person-to-person spread of infection can develop. Aerosolization of this organism as a weapon of biological terror could potentially cause many thousands of casualties, mass social disruption, and widespread fear. Plague pneumonia is treatable if recognized early but still carries a 50% to 60% mortality rate. Delay in therapy is associated with 100% mortality rates. Prophylaxis of exposed persons with oral antibiotics is indicated. There is no protective vaccine currently available.