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Dallas in state of emergency over West Nile virus

Texas health department says at least 10 have died from infections

West Nile virus outbreak

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.