By Marice Richter
DALLAS, Oct 17 (Reuters) - The number of West Nile virus cases across the United States has topped 4,500, with another 282 cases reported last week, making 2012 the nation's second-worst year on record for the mosquito-borne disease, government figures showed on Wednesday.
The Centers for Disease Control and Prevention said 4,531 cases have been reported this year, the highest number since the record outbreak of 2003, when 9,862 cases were reported.
Another 15 deaths from the disease were reported last week, bringing the total to 183, the CDC said.
Almost 70 percent of the cases have been reported in eight states: Texas, California, Louisiana, Mississippi, Illinois, South Dakota, Michigan and Oklahoma. More than one-third were in Texas, with Dallas-Fort Worth at the center of the outbreak.
Just over half of the cases reported to the CDC this year have been of the severe neuroinvasive form of the disease, which can lead to meningitis and encephalitis.
The milder form of the disease causes flu-like symptoms and is rarely lethal. (Editing by Paul Thomasch and Doina Chiacu)