And worse more than half of the infections since the out break began are more serious versions that have higher fatality rates than the infections that just express as a bad flu.

DALLAS (Reuters) – The number of U.S. cases of West Nile virus rose 25 percent in the latest week, putting the 2012 outbreak of the mosquito-borne disease on track to be the most severe on record in the United States, health officials said on Wednesday.

It’s already the worst year ever in Texas, they said.

So far this year, 1,993 cases have been reported to federal health officials, up from 1,590 reported the week before, the Centers for Disease Control and Prevention said in its weekly update of outbreak data. A total of 87 people have now died from the disease, compared with 66 reported one week ago.

The disease has been reported in people, birds or mosquitoes in 48 U.S. states, so far absent only in Alaska and Hawaii. About half of all human cases are in Texas, the CDC said.

Of the nearly 2,000 cases reported to the CDC this year, 1,069, or 54 percent, are 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.

Texas, the outbreak’s epicenter, has had 40 deaths and 495 neuroinvasive cases this year, said Dr. David Lakey, commissioner of the Texas Department of State Health Services.

About a quarter of the cases have been in Dallas County, he said. “This is our worst year ever in Texas,” Lakey said.
The previous Texas record was in 2003, when there were 40 deaths and 439 neuroinvasive cases. Texas has had 1,013 cases overall this year, Lakey said.

CDC figures – which sometimes lag behind state data – show that South Dakota has the next-highest number, with 119 cases and two deaths. More than 70 percent of the cases have been reported from Texas, South Dakota and four other states: Mississippi, Oklahoma, Louisiana, and Michigan, the CDC said.

Do not leave standing water near your house and wear bug repellent when outdoors.