[Yersinia pestis as a dangerous biological weapon]

Plague is an infectious disease caused by the Yersinia pestis microorganism, which is transmitted to the human host from a natural reservoir (different rodent species) by a flea bite. Plague is still encountered in humans in the areas of its enzootic prevalence in local rodent populations. Infection by flea bite results in a bubonic or septicemic plague, possibly complicated by secondary pneumonia. The person with pneumonic symptoms may be a source of a droplet-borne inhalatory infection for other people who consequently develop primary pneumonic plague. Despite a clinical form, plague is a severe infection characterized by a short incubation period, rapid onset and quick progress with mortality exceeding 50% if not treated properly. The pneumonic plague is associated with a particularly rapid progress and the mortality rate of almost 100% if not treated properly. As Yersinia pestis can be easily obtained and cultured and is highly pathogenic for humans, it poses a serious threat of being used for bioterrorism purposes. Artificially created aerosol containing plague bacilli can cause numerous and almost simultaneous cases of primary pulmonic plague in an exposed population. Persons exposed would most likely develop severe pneumonia with rapidly progressing respiratory and circulatory failure. The use of the Yersinia pestis strains resistant to antibiotics typically applied cannot be excluded.