West Nile Cases Triple in One Week
Virus Quickly Spreading Westward, Worst May Be Yet to Come
WebMD News Archive
Aug. 7, 2003 -- This year's West Nile virus outbreak is already outpacing last year's and showing some disturbing new trends that have health officials reaching for the mosquito repellent.
According to the CDC, the number of people infected with the West Nile virus has more than tripled in the last week alone to at least 164 people in 16 states compared to only 112 cases in four states that were reported at this time in 2002. So far this year, the CDC attributes four deaths to the virus.
"The bottom line is that it's here, it's happening in a lot of jurisdictions, every sign indicates that it's on the increase, and now is the time to for people to step up their efforts to fight the bite," says CDC Director Julie Gerberding in a telebriefing today.
Gerberding says that so far all 164 West Nile cases have been attributed to mosquito bites, and the disease does not appear to be spreading through other means. The CDC recently began screening the blood supply for the West Nile virus to prevent transmission of the virus through infected blood.
Disturbing New Trends
Aside from outpacing last year's outbreak, officials say the West Nile virus also appears to be acting in some other troubling new ways.
In previous years, the virus primarily affected older people and caused the most serious illness in senior citizens. So far this year, the average age of Americans infected with the West Nile virus is 45 compared to 55 in last year's outbreak.
Gerberding says it's too early to draw conclusions about the age of West Nile victims, and that change might be due to better reporting of milder cases of West Nile illness among younger people.
The West Nile virus causes two types of illnesses in humans: brain swelling disorders known as encephalitis or meningitis that are responsible for most of the deaths attributed to the virus, and a less serious flu-like West Nile fever that may not require hospitalization.
Virus Spreading Westward
The first U.S. cases of West Nile virus in humans were discovered in the Northeast in 1999 but since then the virus has quickly spread across the country. Last year, several states in the Midwest and South were among those hardest hit by the virus, and now the virus appears to be spreading westward.