Plague (Black Death) 

Occurs after earthquakes, and natural disasters where there is increased contact with wild rodents.

Often a plague is heralded by large amounts of dead rats.

A flea transmits the bacteria from rats to people.

Symptoms start between hours to as long as 17 days after the initial flea bite, and include headache, high fever, muscle aches, and nausea. Lymph nodes become inflamed and become buboes, which may enlarge and develop abscesses.

The infection may spread to blood (causing septicemia) or lungs (pneumonic plague), which is then contagious by coughing.

The patient may also have increased bleeding.

Diagnosis is with a blood test and treatment includes tetracycline or similar antibiotics.
The plague vaccine is not given for travelers (more so for lab personnel).
Plague (Black Death) links

insecta-inspecta.com/ http://www.insectainspecta.com/fleas/ bdeath/Black.html

CDC http://www.cdc.gov/ncidod/dvbid/plague/

WHO http://www.who.int/csr/disease/plague/en/