Insects are shaking off the winter cold in the West, promising another season of the West Nile virus, the mosquito-borne killer that has infected thousands of people — killing 564 of them — since the first domestic case turned up in New York in 1999.
For two-thirds of the country, the crisis has largely passed. But in the West, health officials are drawing up battle plans from the apple orchards of western Colorado to the California coast.
Carried by birds bitten by infected mosquitos, the incurable virus hasn't yet hit the West hard, except in Colorado. But few states are waiting.
Wyoming has earmarked $1.7 million for mosquito-control programs, up from $387,000 last year. Arizona officials have doubled their budget.
California mosquito districts began work earlier than usual this year and in expanded areas. Sentinel flocks of chickens — which can be easily tested for infection to determine the virus' spread — were tested through the winter and the virus was found for the first time in Ventura County earlier this year.
On the western slopes of the Rockies, there is a fear that Colorado could again be ground zero after leading the nation last year with 2,947 of 9,858 overall cases — and 61 of the year's 262 deaths.
Keith Lucy, an environmental health officer in this western Colorado town, and mosquito control officer Jim Terrazas, recently inspected a marsh behind a park popular with the locals for picnics and fishing. Half the marsh is owned by a man who doesn't want mosquito control officers on his land. The owner of the other half, however, has given his consent for the use of larvicide, which kills soon-to-be mosquitos.
That places Terrazas in a dilemma. What good does it do to treat only half the water?
"It's a waste of taxpayer money," he said.
Lucy moves on to the Escalante State Wildlife Area along the Gunnison River, where officials would like to flood the banks to help two endangered species of fish spawn. That raises the possibility of more standing water — prime breeding ground for mosquitoes.
Not only that, wildlife area manager Mike Zeman won't allow adulticide — a pesticide designed to kill adult mosquitoes that is often spread as clouds of machine-generated fog — on the 7,500-acre refuge.
"Fogging is non-selective," he said. "You're hitting all kinds of insects and we have all kinds of birds who feed on those insects."
Lucy looks a little stunned. "The thing here is their primary focus is on wildlife habitat, but mosquitoes breed here and they don't stay here," he said.
Killing adult mosquitoes also can mean spraying with Malathion, a toxic chemical known to cause illness and genetic mutations.
Last year, residents of nearby Paonia protested a plan to spray the chemical and someone bombed a warehouse where Malathion was stored. No one was injured.
"It was a not so subtle message that this is not the way you want to control mosquitos here," Lucy said. "That's the dilemma we're in."
Lucy and his colleagues also are constrained by a budget of just $25,000.
"You get as much public health as you want to buy," said Bonnie Koehler, the deputy director of the Delta County health department. "If you want to give me a hundred thousand dollars, I can give you the George Lucas mosquito control plan the likes of which you have never seen."
Fifty miles away in Grand Junction, crews will soon begin dropping cork-shaped larvicide "briquettes" through more than 3,000 city storm grates. They'll have to revisit the drains every month through October. Larvicide also will be spread in city ponds, practice fields and parks where watering creates pools of water, golf course ponds, and pastures and farmland.
Steve DeFeyter, the Mesa County environmental health director, will trap mosquitoes and sample catch basins in Grand Junction for larvae to determine how well the war is going.
He also has laid the groundwork for an adulticide campaign, if necessary.
"Nobody wants to get into that because it raises such controversy," DeFeyter said. "But if it gets to a public health emergency, then it's the only option you have left to protect the public health."
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