West Nile Virus: Who's at Risk?
As Cases Climb, Experts Answer the West Nile Virus Questions Everyone Asks
Who is most at risk? continued...
Information on infants is limited, Staples says. While there have been periodic reports of infants infected, she could not cite an exact number since the virus was first identified.
"So far this year, we are only aware of one [infected] infant that has been reported," she says.
Infants don't seem to be at increased risk for severe illness, she says, ''but that is based on limited data."
The virus was first identified in the U.S. in 1999.
What is a typical time frame from bite to symptoms?
From bite to symptoms can take three to 12 days, Staples says. "It's usually three to six."
Typically, first symptoms include fever, chills, feeling poorly, and lacking an appetite, Schaffner says.
At that point, especially if you live in a highly affected area, it is reasonable to call your doctor, he says.
It could well be something else, such as a urinary tract infection, he says.
If you are infected, what is the usual course?
"The people who develop the less severe illness report feeling sluggish for weeks or [sometimes] months," Staples says.
"For those who develop the more serious complications, about 10% will die."
Those who survive can have long-lasting neurological effects. One example is a condition called acute flaccid paralysis. The patient is unable to move arms or legs. That is rare, she says.
Long-lasting kidney effects may occur, says Schaffner. Preliminary research has found a gradual decline in kidney function in some patients.
"It is a slight decline, but it is progressive," he says. "There is no sense yet this will lead to kidney failure."
More research and follow-up is needed, he says.
There is no specific antiviral medicine for the infection, Schaffner says. Doctors instead treat the individual symptoms of each person.
What is the best way to avoid getting infected with West Nile virus?
After avoidance, experts advise using insect repellents with DEET, but not in infants less than 2 months old.
Schaffner has some more suggestions:
- Parents can avoid taking walks with infants early in the morning or at dusk.
- Put mosquito netting over baby carriages and apply repellent to the carriage itself.
- When outdoors, wear long pants and long sleeves.
- Remove standing water from around your house, including in gutters, kiddie pools, and potted plant saucers.