The outbreak of the West Nile virus this year has been "one of the largest" since the virus first appeared in the country in 1999, with three times the usual number of cases being reported for this time of year, U.S. health officials say.  

Two weeks ago, 1,118 illnesses have been reported, about half of them in Texas, according to the Centers for Disease Control and Prevention. In an average year, fewer than 300 cases are reported by mid-August. There have also been 41 deaths this year.

Illinois has Twelve Cases

The DuPage County Health Department says the county west of Chicago now has a dozen known human cases of West Nile virus. The department said in a news release Tuesday that people infected with the disease range in age from the 20s to the 70s and live all over the county. One case has proven fatal.

West Nile cases are up this year in many areas across the country affected by drought.

Health officials say one in five people infected will show symptoms such as fever, headaches, vomiting and diarrhea. Less than 1 percent of those infected will develop serious problems but people older than 50 or those with medical conditions such as cancer, diabetes and high blood pressure are at greater risk for serious illness.

Minnesota has Nine Cases

Health officials have confirmed another nine cases of West Nile virus in Minnesota over the past week.

That brings Minnesota's total to 44 for the year, including one death. Nearly 1,600 cases of the mosquito-borne illness have been reported nationwide.

Minnesota Department of Health epidemiologist Dave Neitzel says the number of new cases should start to decline later this month.

Neitzel says the final 2012 total should be well below peak West Nile years. He tells Minnesota Public Radio News (http://bit.ly/RIDVOX ) that as mosquito numbers decline in September, the state also should see a drop in the number of new cases. 

Minnesota's highest number of West Nile cases came in 2003, when the virus caused 148 illnesses and four deaths.
 
Colorado - Two Die

Colorado health officials say two people have died from the West Nile virus this season, both residents of Montrose County in the southwestern part of the state.

The state Department of Health and Public Environment listed the deaths on its website on Tuesday.  Health officials don't identify West Nile victims. The Montrose Daily Press reports (http://tinyurl.com/ce4cvrl ) that an obituary for 86-year-old Dorothy Iris Meaker of Montrose County listed the virus as a contributing factor in her death.

The health department has reported a total of 33 West Nile cases in 12 Colorado counties this season, including the two deaths.

Delta County has the most cases, eight. Montrose is second with six cases, including the deaths. Mesa County has five.

Reported and written by the Associated Press.

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