The state's public health director reported Thursday there's been a second known human case of the West Nile virus in Illinois.
Doctor John Lumpkin says the 57-year-old Madison County man became critically ill with encephalitis. He has since has showing signs of improvement. He remains hospitalized, but has been moved from the intensive care unit.
Lumpkin says the man first reported feeling ill in mid-July and was admitted to a hospital about a week later with fever, headache, stiff neck, confusion and agitation.
The announcement comes two days after an announcement that a 22-year-old Maryland resident who spent eight weeks in Illinois, went home after becoming ill also had the virus. Although he is now in Maryland, it is considered an Illinois case since he contracted it there.
So far, the virus had been found in 218 birds, 105 mosquito bites and three horses. One of the horses died.
A 55 year-old man with a severely compromised immune system is the first confirmed case of West Nile Virus reported among residents of the District of Columbia. He is being treated at a hospital in Maryland.
Doctor Michael Richardson at the National Institutes of Health Hospital in Bethesda says the man is severely ill, but stable.
The man was diagnosed when he was having a regular check-up at the facility where he is being treated for leukemia. Doctor say the leukemia and the medications he's taking for that left him with a highly weakened immune system.
He lives in an area of the District were several birds have tested positive for West Nile virus, and health department employees are trying to find potential breeding sites for mosquitoes in that area.
A number of dead birds with the virus have been found in northern Virginia in recent months.
Acting D.C. health director James Buford says the confirmed case puts the District on notice that West Nile Virus is a threat that exists locally. Buford says steps are being taken to provide information to District residents on how to prevent the spread of the disease by controlling mosquitoes.
This year's victims of the mosquito-borne West Nile virus are younger than in previous years, government health officials reported Thursday.
The Centers for Disease Control and Prevention reported 112 human cases in 2002, more than half in the past week as the disease has moved south and west to states including Louisiana, Mississippi, Texas and Illinois.
The median age for this year's infections is 55. That age is younger than in previous years, when the median age was in the mid-60s.
"The reason patients seem to be younger this year is unknown and certainly something we're looking into," said Dr. Lyle Petersen, a CDC West Nile expert.
Petersen said advanced age remains the biggest risk factor for getting sick from the bite of an infected mosquito. Health officials don't compile statistics for other health problems young West Nile victims had, but they suspect many have a condition that weakens their immune systems.
Men made up 60 percent of this year's West Nile cases, consistent with years past. Petersen said a likely explanation is that men spend more time outdoors.
As CBS News Correspondent Bob McNamara reports, it is Louisiana that is feeling the brunt of the epidemic, the worst outbreak in U.S. history.
Louisiana health officials predicted the West Nile virus epidemic would worsen, and it has. Louisiana Gov. Mike Foster has declared a state of emergency and is asking federal officials for money to beef up mosquito-killing efforts.
Other cases have been reported in Mississippi, Texas and Illinois. Two other human cases were announced this week, in Alabama and Washington, D.C., but were confirmed too late to be included in the CDC report.
Five people have died so far this year, all of them in Louisiana.
Since its first appearance in the United States in New York in 1999, the virus has been detected in 34 states and Washington, D.C. Nearly every state east of the Rocky Mountains has discovered the virus in dead birds, from Maine to North Dakota to Texas.
Most people bitten by an infected mosquito will not become noticeably ill, but some develop flu-like symptoms. Some develop encephalitis, a potentially fatal brain infection. State and local officials have boosted mosquito-spraying efforts and urged people to protect themselves by using mosquito repellent and removing standing water.
The government gave more details Thursday about the Louisiana outbreak, mapping parishes where human infections have occurred. Most were in swampy areas between Baton Rouge and New Orleans in southeastern Louisiana, although some cases were reported in the north of the state.
Encephalitis is usually seen in August and September, but Louisiana's first patients became ill in June.
The West Nile virus is showing up earlier in the summer as it spreads to warmer climates, said Dr. Jim Hughes, director of the infectious diseases center at the Centers for Disease Control and Prevention.