West Nile outbreak
Federal health officials say the current West Nile outbreak is one of the largest in the U.S., with four times the usual number of cases for this time of year.
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Dallas
A Beechcraft airplane sprays the insecticide DUET over Dallas to curb the spread of West Nile virus early Monday morning, Aug. 20, 2012.
The last time Dallas used aerial spraying to curb the mosquito population, Texas' Lyndon Johnson was in the White House, Mission Control in Houston was launching Gemini missions and encephalitis was blamed for more than a dozen deaths.
Credit: AP Photo/LM Otero
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