Plague

The best known of the human infections transmitted by fleas is plague, whose causative organism is Yersinia pestis. The reservoir hosts are various species of rodents and historically the black rat (Rattus rattus) was considered the main reservoir host during the great epidemics that ravaged Europe from the sixth century to until 1720, when the last major outbreak occurred in Europe, in Marseille. The pandemics of plague from the thirteenth century resulted in the deaths of tens of millions of people in Europe. Though plague remains endemic in many foci in Africa, Asia and the Americas, there are now no foci in Europe other than the natural foci of plague in the North Caucasus.

There are, however, a number of other flea-borne diseases of man endemic in Europe, some of which are emerging diseases while others, like murine or endemic typhus, are well known.

Flea-borne rickettsial diseases

Murine typhus

Murine typhus (endemic typhus), whose causative agent is Rickettsia typhi, has a worldwide distribution. Rodents, most often rats (Rattus norvegicus, R. rattus) are the reservoir hosts. Transmission from rodent to rodent or to humans is by contamination with rickettsia-infected flea faeces or tissue during or after blood-feeding by the flea by the faeces or tissues being rubbed into skin abrasions or into delicate mucous membranes. Murine typhus is usually a benign acute, febrile disease, characterized with headache and rash and a fever that persists for about 12 days. Mortality is low and more common in elderly patients.