West Nile virus yet to appear | PostIndependent.com

West Nile virus yet to appear

Donna GrayPost Independent Staff

Recent wet weather in the Roaring Fork Valley has kept mosquitoes at bay, and that means a lower likelihood of anyone contracting West Nile virus.This spring Colorado Mosquito Control, which Garfield County and local municipalities hired, has been hard at work mapping where adult mosquitoes are appearing, and applying larvacide to their breeding areas. The company was hired last year and was instrumental in keeping mosquitoes to a minimum in the county. In 2004, Colorado had the highest number of people with the disease in the nation, with 271 reported cases and three deaths. Garfield Countys mosquito control program helped keep the numbers of cases down to four last year, while neighboring Mesa County had the highest in the state, with more than 200 cases and three deaths. No one died in Garfield County.So far this year, no human cases of the virus have been reported, said Cindy Parmenter, representative for the Colorado Department of Public Health and Environment. One bird, an owl in Weld County, tested positive for the virus earlier this year. There have been no reported cases of horses with the virus.West Nile virus in humans can lead to meningitis, an infection of the spinal fluid, or the sometimes-fatal encephalitis, an inflammation of the brain.The virus has spread west year by year since its first identification in this country in 1999. But once it has infected a resident population of culex mosquitoes, it stays in that population forever.Culex tarsalis and other culex species of mosquitoes carry West Nile virus and are infected after they bite birds that carry the disease. Mosquitoes can spread the virus to humans, horses and other birds.Weve seen adult mosquitoes from Parachute to Silt, said Cynthia Page, who heads the Colorado Mosquito Control effort in Glenwood Springs. Most of the insects are of the annoyance variety, she said, and only a few are culex mosquitoes.Weve had very low numbers (of mosquitoes) at this point. We feel the cold temperatures have helped out in terms of keeping the population down and because weve had a lot of rain, she said. But high temperatures and dry weather could bring them out.Weve seen very few mosquitoes upvalley from Silt, and were concentrating our larvacide efforts on Battlement Mesa, Parachute, Silt and Rifle.Although the outlook is good on the mosquito front right now, its also important to take precautions to reduce the likelihood of exposure to West Nile virus.The key to averting West Nile virus is to put is succinctly, fight the bite with a pre-emptive strike, said Douglas H. Benevento, executive director of the CDPHE. We need to take the disease seriously and to take the proper precautions such as the appropriate use of mosquito repellents and the removal of mosquito breeding grounds.The Centers for Disease Control and Prevention recommend repellents containing 10 to 30 percent DEET and products containing Picaridin and oil of lemon eucalyptus.Although culex mosquitoes are beginning to appear in Colorado, none has tested positive for the virus. However, its just a matter of time, said CDPHE epidemiologist John Pape.The diseases peak season will occur later in the summer when the peak population of these mosquitoes is reached and sufficient numbers of mosquitoes have become infected, Pape said, which is expected to occur in late July through mid-August.A typically wet spring followed by a hot summer, can increase the population of infected mosquitoes, he added.


Start a dialogue, stay on topic and be civil.
If you don't follow the rules, your comment may be deleted.