County prepares for war against West Nile Virus

County pest control squads are facing challenges – from rice fields to abandoned pools and even wildfires – as they try to step up the fight against mosquitoes carrying the West Nile virus.

Reports of virus-killed birds – the marker for West Nile’s arrival – reached the Sacramento Valley this week. Glenn County reported discovering its first dead bird last week and may have located two others, whose bodies authorities have sent to the University of California, Davis, to test for the virus.

The virus, first reported in California in 2003, attacks humans and horses as well as birds. Although 80 percent of infected people show no symptoms, a small number – less than 1 percent of the total – suffer severe flu-like conditions, nerve damage, paralysis and sometimes death. The mosquito species Aedes melanimon passes along the microbe, which can take more than two weeks to show its effects.

Only one Californian has fallen ill from West Nile this year, in Tulare County. But the state Department of Health has recorded at least 160 birds felled by the virus so far, compared to 57 at the same time last year.

One wild card has been the battle against dozens of wildfires in Tehama and Butte counties, which fouled valley air with thick smoke for most of last week. Poor visibility shut down air-spraying efforts in Colusa County, where the mosquito district was to resume its night flights Thursday after a 10-day layoff.

“It depends on how many fires we have,” said David Whitesell, manager of the Colusa Mosquito Abatement District. “If we have more lightning strikes, it could give us problems throughout the mosquito season. It looks cool by day but at night when you get that inversion, it really pushes the smoke down.”

Aerial spraying is not part of Tehama County’s control effort, but weather conditions have interfered even with insect-fighting efforts on the ground, according to Andy Cox, manager of the county Mosquito and Vector Control District. The agency’s six workers cut down their spraying schedule in June first because of high winds and later because of the fires, resuming their campaign June 27.

“We really need to keep down the threat,” said Cox. “The first half of July is notorious for being the peak time for these mosquitoes.”

Throughout the valley, counties are waging much of their war on mosquitoes even before they can fly. District workers are treating stagnant, watery areas – from farm fields to pastures and even unused pools behind foreclosed houses – to kill mosquito larvae before they reach adulthood, and the districts also are giving out free mosquito fish that feed off the immature insects.

“Percentage-wise, we’re doing much better job because we’re identifying and surveying mosquito sources even before they hatch,” said Jack Cavier, manager of the Glenn County mosquito district.

Regional pesticide spraying against West Nile is expect to last until temperatures fall in October or November.

Contact reporter Howard Yune at 458-2121 or hyune@tcnpress.com.

FIGHTING WEST NILE
Mosquito control districts in the Sacramento Valley

n Colusa Mosquito Abatement District
Area: City of Colusa and surrounding area (northeast Colusa County); part of west Sutter County
Pesticide spraying schedule: Colusa and farming areas, 10:30 p.m. to midnight Monday and Thursday; other unincorporated areas, Tuesday and Wednesday
Mosquito fish available free at the district office, 713 D St., Colusa
Contact: 458-4966

n Glenn County Mosquito and Vector Control District
Area: Glenn County, valley floor
Pesticide spraying schedule: Butte City and the south river area, Monday; Orland and Hamilton City, Tuesday; Artois, Wednesday; north river area, Thursday. Spray programs delayed by weather may be conducted on Fridays, along with spraying by request.
Mosquito fish available free at the district office, 165 County Road G, Willows, and at 1308 Railroad Ave., Orland
Contact: 934-4025

n Tehama County Mosquito and Vector Control District
Area: Tehama County, valley floor
Pesticide spraying schedule: Varies weekly
Mosquito fish available free at the district office, 11861 Old Highway 99W, Red Bluff
Contact: 527-1676

For more information:
n California Department of Public Health: www.westnile.ca.gov

n U.S. Centers for Disease Control and Prevention: www.cdc.gov/ncidod/dvbid/westnile