Mosquitoes test positive for West Nile

Friday, August 21, 2009

GREENCASTLE -- Mosquitoes collected in Greencastle and sent to the Indiana State Department of Health Entomology Laboratory in Indianapolis have tested positive for West Nile virus.

Doug Ehmen, public health coordinator and environmental health specialist for the Putnam County Health Department, said the mosquitoes sent in for testing were collected from an area near the Greencastle sewer plant.

"We just want to remind people that they need to be careful," Ehmen said. "They should continue using bug repellents that contain DEET (N,N-Diethyl-meta-toluamide, an oil that is the most common active ingredient in insect repellents)."

West Nile virus can manifest itself in several different ways: Encephalitis, which is an inflammation of the brain; meningitis, an inflammation of the membrane around the brain and spinal cord; fever; clinical manifestations other than fever, such as acute flaccid paralysis; and clinically unspecified cases.

Ehmen said keeping yards mowed is a good safety measure, as mosquitoes tend to be found in areas of heavy vegetation.

"Mosquitoes also come out more at night," Ehmen said. "They're like us ... they don't like to be out in the hot sun. If you have to be out after dark, wear a long-sleeved shirt and long pants."

For parents who are concerned about exposing their children to DEET, Ehmen said putting insect repellent on clothes can be just as effective.

"You don't have to spray it directly on the skin," he said.

Other safety tips listed at the U.S. Centers for Disease Control Web site (www.cdc.gov) include making sure the screens on windows and doors are free or holes or tears and emptying standing water from flower pots, buckets, barrels and children's wading pools.

Last year, a dead crow collected in Putnam County tested positive for West Nile. So far, Ehmen said, no dead birds have been sent from Putnam County to Indianapolis for testing.

Ehmen said crows, raptors, robins, cardinals and blue jays are among the species of birds that are especially susceptible to West Nile. Should individuals find dead birds of these species, they are asked to call the health department at 653-5210 so they can be sent out for testing.

According to the CDC Web site, no human cases of West Nile have been reported in Indiana this year. There have been 82 confirmed cases and three confirmed fatalities reported nationwide.

Human West Nile cases are tracked through ArboNET, a national electronic surveillance system set up by the CDC. State and local health departments report cases.

Of the 82 human cases reported so far this year, 52 were reported as meningitis or encephalitis, 28 were reported as fever and two were clinically unspecified.

"The high proportion of neuroinvasive disease cases among reported cases of West Nile virus disease reflects surveillance reporting bias," the CDC Web site said. "Serious cases are more likely to be reported than mild cases."

States where West Nile cases have been reported include Arizona, Arkansas, California, Colorado, Idaho, Iowa, Kansas, Louisiana, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New York, Pennsylvania, South Dakota, Tennessee, Texas and Wyoming. The fatalities occurred in Mississippi and Texas.

About one in 150 people infected with the West Nile virus will develop a severe illness. Symptoms of West Nile virus include fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and paralysis in more severe cases and fever, headache, body aches, nausea, vomiting, swollen lymph glands and skin rash on the chest, stomach or back in milder cases.

About 80 percent of those infected with West Nile virus will never show any symptoms at all, the CDC Web site said.

Respond to this story

Posting a comment requires free registration: