Although four out of five people will develop no illness from West Nile Virus (WNV), twenty percent of those infected will experience West Nile fever, leaving 1 in 150 who suffers from severe neuroinvasive disease.
There are different tiers to WNV-related illnesses that vary depending on the person infected. Even those who are asymptomatic may experience long term effects from the illness. According to a report by Khou.com, Dr. Kristy Murray, associate professor of pediatrics at the National School of Tropical Medicine at Baylor College of Medicine stated: "Sixty-to-seventy percent of those individuals are going to have long-effects such as paralysis, memory loss, weakness, being off balance, vision problems, and things like that."
Murray adds that there is in increase in kidney disease among WNV patients.
Symptoms
According to the CDC, the twenty percent who develop West Nile fever will experience symptoms of fever, headache, tiredness, body aches, skin rashes, and swollen lymph glands. While the symptoms have been known to pass after a few days, they may last for several weeks.
Those who develop severe disease run the risk of contracting West Nile encephalitis, meningitis, or West Nile poliomyelitis. Symptoms include: headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, and paralysis. Typically, these symptoms do not afflict healthy people, with anyone over the age 50 or a weak immune system being at the highest risk for illness.
The Big Picture
WNV cases have popped up with increasing regularity over the past few months across every state except Hawaii, Alaska, and Vermont. Dallas, Texas was hit particularly hard, with government officials declaring a state of emergency and called for a statewide aerial pesticide treatment of the city and its suburbs. Houston has also recorded three deaths, and we haven't even reached the peak of the season for WNV cases.
Kristy Murray, an infectious disease specialist in Baylor College of Medicine's National School of Tropical Medicine says that three deaths at this time in the season is "a significant number," but that "we should expect more."
"We are about to hit our peak and we still have another month when the majority of cases are going to occur," she continued.
It is important to note that all three deaths involved people between the ages 55 and 84.
Kathy Barton, spokeswoman for the House Department of Health and Human Services, said: "People who die from the virus typically are elderly or have other chronic health problems, such as diabetes or cancer...Typically a healthy person would not develop a serious infection."
Although there are no vaccines or treatments available to combat WNV, it is important to take measures to prevent infection. Drain standing water, use repellent, wear long sleeves and pants at dusk and dawn, and place screens on doors and windows.