Chickens are on front lines against West Nile

BEND, Ore. – As it turns out, a bunch of chickens in KlamathFalls are on Oregon’s first line of defense against the West Nilevirus.

It is one way that the state continues to try and prepare forthe mosquito-borne virus. Oregon remains the only state in thecontinental U.S. with no reported cases of the virus, according tothe Center for Disease Control and Prevention.

Experts think the disease could be headed this way this summerand are preparing accordingly. That is where the chickens comein.

The so-called “sentinel chickens,” stationed in Klamath Fallsand in other flocks across the state, get their blood drawn everyfew weeks.

The blood is then tested for three mosquito-borne viruses,including West Nile.

“If one of the chickens gets bit [by an infected mosquito], theydon’t get sick themselves. They develop antibodies for it, and theantibodies can be detected,” said Michael Morstad, manager of theKlamath Vector Control District, which owns and cares for thechickens.

State health officials already launched a public educationcampaign about West Nile, but have opted to wait and see whathappens before recommending more aggressive control of mosquitoes,such as spraying with pesticides.

Oregon received a $200,000 grant from the CDC this year, saidEmilio DeBess, public health veterinarian for the state. The statehas not put any of its own money into West Nile preparations, hesaid.

“Most of that money is going into surveillance and education, asthe CDC recommends,” DeBess said. “And then it’s up to the localcommunities to make a decision as to what needs to be done.”

The state has avoided mandating mosquito control in part becauseexperts disagree over the effectiveness of pesticides in stavingoff West Nile infection.

“I would say any [pesticides] would decrease the risk ofinfection because it’s decreasing the mosquito population,” saidChris Kirby, administrator of the pesticides division of the OregonDepartment of Agriculture.

Others say the issue is more complicated.

Professor Phillipe Rossignol, a medical entomologist at OregonState University, referenced a recent study that compared infectionrates among Louisiana counties that sprayed for mosquitoes withthose that did not.

In most states, the virus has first shown up in animals,particularly birds and horses, said Mari DeReus, communicabledisease nurse for the Deschutes County Health Department.

Most people who contract West Nile virus do not exhibit anysymptoms and are believed to develop lifelong immunity, DeReussaid.

One in 150 people who develop symptoms actually die from thevirus, she said.

Last year, 262 people in the United States died from West Nilevirus. About 36,000 die each year from influenza, according to theCDC.