HERMISTON — The West Umatilla Mosquito Control District announced it will conduct targeted ultra-low volume aerial mosquito control spraying with a twin-engine airplane after sunset Monday, Sept. 6, weather permitting.

The application will be scheduled for the following day if the weather causes a cancellation.

According to the press release from the district, a total of 10,240 acres are to be targeted in areas north and east of Hermiston that have high populations of vector and nuisance mosquitoes. The target area includes the Power City area between Highway 395 east to the Highway 730/Diagonal Junction, and south to Punkin Center Road. No areas within city limits are currently scheduled for aerial spraying. Ground trucks will be used within the city limits if necessary.

“People are encouraged to take appropriate precautions to protect themselves against mosquito bites,” the district stated.

The West Umatilla Mosquito Control District reported one positive West Nile virus sample in mosquitoes collected west of Hermiston in early August. Another sample, collected in the Power City area tested positive on Aug. 31. That sample is undergoing confirmatory testing at the Oregon State University Veterinary Diagnostic Lab.

Most people who become infected with West Nile Virus may have a mild illness. People infected with the virus may develop mild flu-like symptoms such as fever, headache, body aches and occasionally swollen lymph glands or a rash. There may be a greater risk of serious illness if you are 50 and older or have immune-compromising conditions such as diabetes and high blood pressure.

In a very few cases, West Nile may cause encephalitis, or inflammation of the brain. Individuals with severe or unusual headaches should seek medical care as soon as possible.

Here are some suggestions to reduce the risk of exposure to West Nile:

• Get rid of old tires and other containers where water can accumulate and serve as a breeding ground for mosquitoes.

• Flush or replace the water in horse troughs weekly.

• Be sure to flush or add mosquito fish to ornamental ponds.

• Avoid outdoor activities at dusk and dawn when mosquitoes are most active.

• Wear long-sleeved shirts and long pants when in mosquito infested areas.

• Use mosquito repellents containing DEET, oil of lemon eucalyptus or Picardin, making sure to follow the directions on the container.

• Screen doors and windows and ensure that they are in good repair.

• Report mosquito infestations and dead bird sightings to your local mosquito or vector control district.

West Nile is primarily a bird disease, and some birds, including magpies, blue jays and crows are especially susceptible. Mosquitoes become infected by feeding on an infected bird and can pass the virus to humans, horses or other hosts when they bite. The district encourages the public to continue to alert district or public health officials when they come across dead birds so the districts can track the spread of the virus.

Because horses also are at risk for West Nile, health officials encourage horse owners to check with their veterinarians for vaccination. Veterinarians can arrange for testing of samples from horses suspected of infection with West Nile Virus at Oregon State University Veterinary Diagnostic Laboratory.

You can find updates about West Nile Virus in Umatilla County on local media outlets and at the Oregon Department of Human Services website: public.health.oregon.gov/DiseasesConditions/DiseasesAZ/WestNileVirus/Pages/survey.aspx.

Additional information on West Nile is online at the U.S. Centers for Disease Control and Prevention: www.cdc.gov/ncidod/dvbid/westnile/.