West nile virus protection for farmers and ranchers

By KYRA KIRKWOOD

For the Capital Press

ORANGE COUNTY, CALIF.–As the dreaded West Nile virus slouches across the nation, ranchers in California can take measures to protect their livestock now before the virus hits home.

The most important thing: "Don't panic," said Dr. John Maas, extension veterinarian at U.C. Davis. He noted that while this type of mosquito-borne, viral encephalitis has garnered excessive media attention lately, similar infections have been around for years. The thing to do now, Maas said, is to be informed and use common-sense techniques for keeping farms and family mosquito-free.

According to the Centers for Disease Control, 39 states–every one east of the Rocky Mountains–have reported either animal or human infections as of August. Officials in the California Department of Health Services say that West Nile will most likely hit the state in the next one to two years.

People and animals, mainly horses, can become infected with the disease after being bitten by mosquitoes carrying the virus. Leticia Rico, public information officer with the California Dept. of Food and Agriculture, says that cattle, dogs and cats are rarely affected.

"They seem to develop immunities," she said.

Birds incubate the disease, carrying it across long distances and spreading it through the mosquitoes that bite them.

"If it does reach here, we'll put forth every effort to control it," he said.

The most important thing ranchers can do to control bugs and protect their animals is to remove any mosquito-breeding areas, such as cans, old tires, plastic containers, buckets and pots filled with stagnant water. These bugs can breed in any puddle that lasts for more than four days, according to Orange County Animal Care Services.

Other ways farmers can protect their farms include:

• Drilling holes in the bottom of recycling containers to prevent a buildup of water;

• Cleaning out clogged roof gutters;

• Turning over wheelbarrows when not in use;

• Emptying and refilling water troughs every few days;

• Stocking ornamental pools with fish;

• Cleaning and chlorinating swimming pools;

• Reducing the number of birds around the stable area;

• Searching the property for dead birds such as crows, but handling them only with gloves;

• Keeping horses in stalls at night.

Since horses are the most-affected livestock, Maas advised ranchers to visit their veterinarians and ask about the West Nile virus vaccination. Boosters will be needed as follow-ups, he said. Although the vaccination is not a foolproof method of protection, it is another step to take, say officials at Animal Care Services.

Signs of the disease in horses may include loss of appetite, depression, fever, weakness, impaired vision, head pressing, seizures and walking in circles. There is no specific treatment for the virus.

"Some will show illness, some will die, some will be immune," said Maas. It should be noted that not all horses with clinical signs of West Nile will have this brand of encephalitis. Veterinary diagnosis is crucial.

"Horses' immune system seems to leave them open to [West Nile]," said Rico.

Although more rare than horse-born West Nile, people can also become infected with the virus. As of Aug. 17, two more people died because of West Nile, bringing the total to 11 in 2002.

"The chances of [mosquitoes] transmitting the disease to humans is very slim" in Southern California, said Francisco.

According to the Centers for Disease Control, 147 people have been infected with the virus in Louisiana, resulting in eight deaths. However, Francisco noted that those who live in high-humidity areas such as the South are more at risk due to the sticky environment and numerous wetlands.

"Wear some DEET," said Maas.

Other precautions include:

• Not turning on bright outside lights at night;

• Reducing outdoor exposure;

• Wearing long-sleeved shirts and pants outside;

• Avoiding mosquito-infested areas at dawn and dusk.

"We don't know when it's coming [to California]," said Francisco. "But we're ready."