SACRAMENTO (June 20, 2007) –

A 21-year-old Kern County woman has tested positive for West Nile virus (WNV) infection, the first reported human case in California this year, State Public Health Officer Dr. Mark Horton announced today.  The woman’s symptoms include fever, headache and body aches. She was not hospitalized.

“This first confirmed illness in California due to West Nile virus reminds us that we are moving into the high-risk season,” Horton said.  “The most important step people can take to prevent exposure to West Nile virus is to protect themselves from being bitten by a mosquito. We are also requesting the public to report dead birds to assist state and local agencies with surveillance efforts.” 

The positive test was reported to the Kern County Department of Public Health by a local blood bank where the patient had donated blood.  She subsequently developed symptoms.

“Special precautions are taken to test all blood donations for West Nile virus, so Californians can be assured that blood supplies are safe,” Horton said.

To date this year, WNV has been detected in 13 of California’s 58 counties in 57 dead birds, 18 mosquito samples, two sentinel chickens and one horse.  In 2006, a total of 278 human WNV cases, including seven deaths, were reported in the 46 of 54 counties that detected WNV activity

WNV is transmitted to humans and animals through a mosquito bite from a mosquito that has been infected by feeding on an infected bird.  Although the risk of serious illness to most people is low, less than 1 percent of individuals will develop a more serious illness.

Horton reminded Californians of three simple ways to protect themselves from WNV:

• DEET – Apply inspect repellent containing DEET, picaradin or oil of lemon eucalyptus according to label instructions.  Repellents keep the mosquitoes from biting you.  DEET can be used safely on infants and children 2 months of age and older.

• DAWN AND DUSK – Mosquitoes that carry WNV bite in the early morning and evening so it is important to wear repellent at this time.  Make sure that your doors and windows have tight-fitting screens to keep out mosquitoes.  Repair or replace screens with tears or holes.

• DRAIN – Mosquitoes lay their eggs on standing water.  Eliminate all sources of standing water on your property, including flower pots, old car tires, rain gutters and pet bowls.  If you have a pond, use mosquito fish or commercially available products to eliminate mosquito larvae.

Governor Arnold Schwarzenegger has invested a total of $15 million over the last two years to enhance mosquito control efforts in California.  This funding has supplemented the resources of existing mosquito control programs statewide and expanded efforts in areas of the state not covered to control WNV.  This investment in equipment and other products to control mosquitoes continues to benefit mosquito control efforts this year.

For more information about WNV, visit www.westnile.ca.gov.  In addition to reporting all dead birds, Californians are encouraged to report dead tree squirrels.  The Web site includes information on the most common birds found with WNV.  Dead birds and squirrels can be reported on the Web site or by calling (877) 968-2473.

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