U.S. health officials reported Wednesday three times the usual number of West Nile cases for this time of year, and one expert called it "one of the largest" outbreaks since the virus appeared in this country in 1999.

So far, 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.

"We're in the midst of one of the largest West Nile outbreaks ever seen in the United States," said Dr. Lyle Petersen, a CDC official. Never before have so many illnesses been reported this early, said Petersen, who oversees the CDC's mosquito-borne illness programs. Most infections are usually reported in August and September, so it's too early to say how bad this year will end up, CDC officials said.

Minnesota has had 20 reported cases this year.

--ASSOCIATED PRESS