Time to Take Action
Our Klamath Basin Water Crisis
Upholding rural Americans' rights to grow food,
own property, and caretake our wildlife and natural resources.


West Nile found in Klamath

Chris Howard, a mosquito inspector and pesticide applicator with Klamath Vector Control District, hangs a mosquito trap on Miller Island Monday evening. The district in charge of keeping mosquito numbers at bay also keeps a watch for signs of West Nile virus.

August 30, 2005 by DYLAN DARLING

The presence of West Nile virus in Klamath County was confirmed by health officials Monday after tests detected the disease in a dead bird found last week southwest of Klamath Falls.

It was Klamath County's first case of the disease that has spread across the country over the past several years, and reached scattered parts of Oregon last year.

A local resident contacted health officials last Wednesday after finding a dead scrub jay.

The bird was tested twice, first by the Klamath Vector Control District and then by Oregon State University's School of Veterinary Medicine in Corvallis.

"It was definitely positive for West Nile," said Michael Morstad, manager of the Klamath Vector Control District.

Morstad said the bird was found within a few hours after it had died. The man who found it had heard that officials were interested in testing dead corvids - jays, crows and magpies - because they are usually the first animal to show that West Nile has arrived in a particular area.

Health officials wouldn't disclose which neighborhood the bird was found in because they don't want to alarm its residents.

West Nile is transmitted by the bite of a mosquito. Birds, horses and humans are most commonly affected, according to the Klamath County Department of Public Health.

The Klamath Vector Control District - the agency responsible for controlling mosquito populations - has been on the lookout for the disease for several years, using two methods.

Three flocks of chickens - dubbed "sentinel chickens" - have been maintained at scattered locations for the collection of blood samples. The district also traps mosquitoes, separates them by species, and grinds them up for testing.

Neither method had revealed any sign of the virus.

Officials have also been asking people to call in if they find a freshly dead corvid. Last year they tested 14 of the birds, but none showed signs of West Nile.

This year vector control is using more accurate testing tools, Morstad said.

"We could have had it last year here and not known it because our equipment was not sensitive enough," he said.

The infected jay was the second bird tested this year.

Alise Barlow, a lab technician at the vector control district, said the bird had a high level of West Nile in it, but the test had to be double checked by the lab in Corvallis.

Barlow said people should be careful about mosquitoes, although the chance of catching the disease is low.

Most people who get West Nile won't realize it. Symptons show in only 20 percent of people infected, and it tends to simulate the flu. But the virus can be deadly for the young and elderly or those with weak immune systems.

The West Nile virus can cause encephalitis, an inflammation of the brain. The virus, which had been found in Asia and the Mediterranean, and came to New York City in 1999. From there is has spread south and westward and now is found in most states.

The virus had spread to Europe from Africa, where was first reported in 1937 in Uganda, according to the Centers for Disease Control and Prevention.

There is a vaccine against the virus for horses, but none for humans.

To keep mosquito numbers down, the vector control district sprays malathion in neighborhoods from pickups, and other pesticides on farm fields from crop dusters.

The tax-supported vector control district's budget this year is $400,000, including $100,000 for chemicals, Morstad said.

The vector district will continue to monitor for West Nile and manage mosquitoes for the rest of the summer.

"We'll keep surveying, keep spraying," Barlow said. "It's all we can do."

To collect mosquitoes, vector controls puts out traps with dry ice as the bait. The dry ice emits carbon dioxide, the same gas that attracts the insects to people.

West Nile has also shown up this year in dead birds in the neighboring counties of Jackson and Josephine, as well as in Malheur county this year.

The virus has also been found in horses in Baker and Harney counties this year.

The virus was detected last year in Siskiyou and Modoc counties in California.

So far, it has not be detected in Lake County.

By far, the biggest West Nile numbers in the United States are to the south in California, where 370 human cases have been reported this year, including 83 in Sacramento County.

"And Sacramento isn't that far from us," Morstad said.

He said it's not clear whether the jay found here last week was infected with the virus in Oregon, or came up with it from California, which is about 10 miles south from where it was found.

For more information call the Oregon Department of Human Services hotline toll-free at (866) 703-4636, or the Klamath County Health Department at 882-8846.

On the Net: www.cdc.gov/westnile






Page Updated: Thursday May 07, 2009 09:14 AM  Pacific

Copyright klamathbasincrisis.org, 2005, All Rights Reserved