Plague hosts

In addition to plaguing humans directly, flies spread pathogens that infect a significant number of plants and animals. Veterinary medicine must deal with horse flies and black flies, as well as pests with such curious names as warble flies and bot flies. There are ubiquitous stable flies that look like everyday house flies but deliver a painful bite, and a multitude of less familiar species that prey on sheep, rodents, and rabbits. Flies that are crop pests typically feed on their plant hosts as larvae. Seedcorn maggots, for... 

Plague is still present worldwide. The introduction of the disease to human populations occurs when plague-infected fleas, which typically infest rodent hosts, cause the death of these rodents in large numbers. Fleas... 

However, despite the advances, these new treatments were plagued by a host of side effects—some unpleasant, some actually dangerous. These potent drugs were also often overused or were misused in certain treatment settings. Consequently,... 

It is caused by the Yersinia pestis bacterium. Rodents are the normal host of plague, and the disease is transmitted to humans by flea bites and occasionally by aerosol in the form of pneumoitic plague. The disease has a history of use in biological warfare dating back many centuries (see Roman times, above), and is considered a threat due to its ease of culture and ability to remain in circulation in rodents for long periods. 

Moran, N.A., Plague, G.R. 2004. Genomic changes following host restriction in bacteria. Curr. Opin. Genet. Dev. 14 627-633. 

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