FILE - In this Aug. 16, 2012 file photo, mosquitos are sorted at the Dallas County mosquito lab in Dallas. U.S. health officials say there's been an alarming increase in the number of West Nile cases. So far there have been more than 1,100 cases reported through the middle of August. That's three times as many as usually seen at this point in the year. About half the cases are in Texas. Most West Nile infections are reported in August and September. (AP Photo/LM Otero, File)
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