Fleas cause itching and red bite marks on their hosts but are nowadays mainly a nuisance. This was not always so. In the Middle Ages they spread bubonic plague from rats to man, causing the Black Death epidemics that killed 25 million people—up to 50% of the Europe’s population. They also transmit the agents causing murine typhus (Rickettsia typhi), tularemia (Francisella tularensis), and cat scratch fever (Bartonella henselae); and may serve as intermediate host for tapeworms, infecting pets and occasionally humans. Dogs and cats are more bothered by fleas because they are hairy, and may develop a flea allergy dermatitis that accounts for a great number of visits to veterinarians. Fleas have also made an impact in the art world, as shown by the woman trying to get rid of them in this painting by the Baroque artist from Bologna, Giuseppe Maria Crespi (1665-1747).

Searcher for Fleas. Giuseppe Maria Crespi. 1720s. Lourve Museum.

Highlighted Vignette Volume 12, Issue 4 – Fall 2020

Fall 2019  |  Sections  |  Infectious Diseases