Plague

This plague is a historical plague. In 14th century it already existed and it caused about 50 million deaths.

It occur in the summer when people are out their houses. Because it transmitted by fleas. Also it transmitted by rodents for that in Canada the government exterminate rodents in the city parks specifically in US National Park Service.
In US:

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The bacterium responsible is (Yersinia pestis) which was introduced by rats in 1900.
It causes affects the lymph nodes and causes gangrene. It can be hard to identify because symptoms developed after three to seven days.

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I think that the government have to help the people who have this bacterium and it isn't necessary to exterminate all rodents, I think that should only make them treatment.

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