If confirmed, it would be the first human case of the virus in the western United States. A spokeswoman for the state health department said the woman has aseptic meningitis -- a condition sometimes associated with West Nile virus.

Test results are expected later today. But the spokeswoman said preliminary tests show possible exposure to the virus. There's no word on whether she became sick in California or elsewhere.

In Oregon, doctors in Salem are treating a woman who also has symptoms consistent with West Nile virus. The woman became sick in Michigan.

More and more cases of West Nile virus infections are being reported to the Centers for Disease Control and Prevention every day.

As of Thursday, the CDC reported 43 deaths and 854 human infections from the virus in 28 states and the District of Columbia so far this year.

The CDC expects many more cases of West Nile virus infection to be reported in the coming weeks as the transmission season peaks in different parts of the country.

The agency is continuing to investigate a cluster of cases of West Nile virus infection through transplantation of organs from one donor. So far, three people who received organs from a single donor have been diagnosed with encephalitis due to West Nile virus. And Thursday, a fourth organ recipient tested positive for West Nile virus fever, a milder form of the infection.

The donor's infection remains under investigation; it is most likely that the donor became infected with the virus through a mosquito bite or by blood transfusion shortly before organ donation, CDC officials said in a press release.

As a precaution, remaining blood products from donors of blood given to the organ donor as well as to the organ recipients have been voluntarily withdrawn from use. Recipients of blood products from these donors will be contacted and tested for West Nile virus.

The CDC is also investigating a case of West Nile virus infection in a Mississippi woman diagnosed nearly four weeks after receiving 18 units of blood during an obstetrical procedure in July. She has since recovered.

The patient reported having been bitten by mosquitoes on numerous occasions before hospitalization. However, as a precaution, remaining blood products from donors of blood to the patient have been voluntarily withdrawn from use.

No blood screening test for West Nile is available. So the investigation prompts concern that the virus could travel through the blood supply undetected.

However, health officials assure the public that blood transfusions are safe.

Since exposure to the virus through a mosquito bite is the principal means of acquiring infection, the CDC continues to urge people to take steps to protect themselves from being bitten by mosquitoes. These steps include eliminating standing water from around the home where mosquitoes are likely to breed, wearing long sleeves and pants, and wearing insect repellents that contain DEET.

-- Anonymous, September 07, 2002