Plague is caused by Yersinia
pestis, a gram-negative, nonmotile,
It is a zoonotic disease, and rodents
are the primary reservoir.
Plague can present as bubonic,
pneumonic, or primary septicemic disease.
Y pestis is usually transmitted to
humans via the bites of infected fleas,
causing the bubonic form of the disease.
Primary septicemic and secondary
pneumonic disease are much
less common. Primary pneumonic
disease results from aerosol exposure
to an infected animal or human with
plague pneumonia; however, it too has
become uncommon as a natural event.
Nonetheless, primary pneumonic
plague, or a similar illness, is the most
likely manifestation following a bioterrorist
attack.1,2 Despite the substantial
investment by the former Soviet Union
in this agent as a potential weapon,
there is little experience from which
to predict the clinical consequences
of intentional aerosolization of this