Plague is enzootic in wildlife populations of small mammals in central and eastern Asia, Africa, South and North America, and has been recognized recently as a reemerging threat to humans. Its causative agent Yersinia pestis relies on wild rodent hosts and flea vectors for its maintenance in nature. Climate influences all three components (i.e., bacteria, vectors, and hosts) of the plague syste...

Sylvatic plague, or plague of wild rodents is caused by Yersinia pestis and entered California (USA) from Asia about 1899. Extensive sampling during the 1930's and 1940's documented the spread of plague to approximately its current distribution in North America. Records from the Centers for Disease Control and Prevention document plague in Kansas (USA) between 1945 and 1950, but since then ther...

The public and clinicians have long-held beliefs that pneumonic plague is highly contagious; inappropriate alarm and panic have occurred during outbreaks. We investigated communicability in a naturally occurring pneumonic plague cluster. We defined a probable pneumonic plague case as an acute-onset respiratory illness with bloody sputum during December 2004 in Kango Subcounty, Uganda. A definit...

but, as Kupferschmidt rightly argues here, it was already overturned by French investigations in the Near East in the decade after the publication of Hirst's study. It is now clear that there are three primary means for the spread of plague: (1) transmission by sylvatic rodent populations, which in man results in sporadic endemic plague; (2) major outbreaks in rat populations, which cause pande...

In his book The Black Death transformed, Samuel K Cohn claims that the epidemic disease described in western European historical sources from AD 1347 to the midseventeenth century under the names plague, pestis, pestilence, plagen and the like must have been a disease other than the modern plague that reached Hong Kong in May 1894 from other parts of China, and later spread first to India and t...

BACKGROUND Yersinia pestis is the pathogen of the plague and caused three pandemics worldwide. Pneumonic plague is rarer than bubonic and septicemic plague. We report detailed clinical and pathogenic data for all the three sporadic cases of pneumonic plagues in China in 2014. CASE PRESENTATION All the three patients are herders in Gansu province of China. They were all infected by Yersinia pe...