West Nile virus outbreak

LiveScience.com
Why Is West Nile Virus So Bad This Year?

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The United States is experiencing its worst seasonal outbreak of the mosquito-borne West Nile virus. A total of 3,545 cases, including 147 deaths, were reported in the United States in 2012, the highest human toll by that point in the calendar since the mosquito-borne disease was first detected in the country in 1999.

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