Two West Nile deaths in Montrose County
Two Montrose County residents are the first two Coloradans infected with the West Nile virus this year to die.
Both died of complications related to West Nile-caused encephalitis, or inflammation of the brain, within the last week, according to Montrose County Health and Human Services Director Peg Mewes.
Less than 1 percent of people infected with the West Nile virus develop a severe illness such as encephalitis, according to the Centers for Disease Control and Prevention. Roughly one in five people infected with the virus develop less-severe West Nile fever, with symptoms including fever, headache, body aches, rash, fatigue and swollen lymph glands. Signs a person with the West Nile virus has developed a more severe illness include high fever, neck stiffness, disorientation, coma, convulsions, muscle weakness and paralysis.
People older than 50 years old are more at risk than younger people to develop West Nile encephalitis, according to the CDC.
Mewes said Montrose County Health and Human Services has chosen not to release the ages and genders of the two Montrose County residents who died while infected with West Nile. The Associated Press identified one of the victims as 86-year-old Dorothy Meaker of Montrose.
Six of the state’s 33 reported human cases of West Nile virus infection in 2012 as of Aug. 31 have been found in Montrose County, according to the Colorado Department of Public Health and Environment. With eight confirmed cases, Delta County leads the state in human West Nile infections this year.
Mesa County had five human cases as of the end of August, with two cases each of West Nile meningitis and West Nile fever plus one case of West Nile encephalitis. One horse tested positive for the virus in mid-August in Mesa County and two Mesa County mosquito populations tested positive for infection last month.
Drought conditions have made it harder for mosquitoes that rely on stagnant pools of river water to breed, according to Zane McCallister, manager of the Grand River Mosquito Control District, which stretches from Fruita to Palisade but excludes most of the city of Grand Junction. McCallister said the drought hasn’t touched the breeding grounds of Culex tarsalis mosquitoes, however, which are more likely than other mosquito species to carry the West Nile virus and prefer to procreate in storm drains, swimming pools and irrigation runoff lines.
McCallister said he has found fewer mosquitoes overall in district traps this summer but more potential West Nile carriers.
“Last year about 35 to 40 percent of mosquitoes (we caught) were Culex tarsalis. The percentage that are Culex tarsalis is much higher this year, closer to 70 to 80 percent,” he said.
McCallister said the mosquito control district concentrates mostly on killing young mosquito populations using a biological herbicide in watery breeding grounds and sprays for mosquitoes “as a last resort.”