Concept
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Plague

A flea infected with yersinia pestis
A flea infected with yersinia pestis, shown as a dark mass. The foregut of this flea is blocked by a Y. pestis biofilm, which is a prerequisite for efficient transmission.
Source
Boundless vets and curates high-quality, openly licensed content from around the Internet. This particular resource used the following sources:
"Flea infected with yersinia pestis."
http://en.wikipedia.org/wiki/File:Flea_infected_with_yersinia_pestis.jpg
Wikipedia
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