The bacteria that cause plague, Yersinia pestis, maintain their existence in a cycle involving rodents and their fleas. In urban areas or places with dense rat infestations, the plague bacteria can cycle between rats and their fleas. The last urban outbreak of rat-associated plague in the United States occurred in Los Angeles in 1924-1925. Plague bacteria are most often transmitted by the bite of an infected flea. Plague-infected fleas usually bite rates or mice, but dogs and cats may also bring infected fleas into the home. Question: who is the host and who is the agent?

The bacteria that cause plague, Yersinia pestis, maintain their existence in a cycle involving rodents and their fleas. In urban areas or places with dense rat infestations, the plague bacteria can cycle between rats and their fleas. The last urban outbreak of rat-associated plague in the United States occurred in Los Angeles in 1924-1925. Plague bacteria are most often transmitted by the bite of an infected flea. Plague-infected fleas usually bite rates or mice, but dogs and cats may also bring infected fleas into the home. Question: who is the host and who is the agent?

BIOLOGY:CONCEPTS+APPL.(LOOSELEAF)

10th Edition

ISBN:9781305967359

Author:STARR

Publisher:STARR

Chapter43: The Biosphere

Section: Chapter Questions

Problem 3CT

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