BAKERSFIELD, Calif. -- Kern County has more cases of West Nile virus than any other county in the state, according to data released by a state agency.

The county has 22 known human cases of the virus; seven of those are clustered within an area of Northeast Bakersfield.

Last week, a 96-year-old woman was the first to die of the disease. Marguerite Wilson lived in the area where most of the cases are located.

Despite the cluster of West Nile virus cases, public health officials said there is no one explanation for it.

Dr. Boyce Dulan, with the Kern County Public Health Department, said the virus tends to begin in one area and spread out as the summer months progress.

The disease is transmitted through birds infected with West Nile virus. Mosquitoes feed off the blood of infected birds and pass on the virus to humans.

Residents in Northeast Bakersfield said they are concerned about the cluster of West Nile virus so close to their neighborhoods.

Kern Mosquito and Vector Control officials warn the public to eliminate standing water around their homes to prevent breeding pools for mosquitoes.

Health officials said people should take preventative measures to safeguard against the virus.

* Avoid dawn and dusk hours, when mosquitoes are must abundant.

* Wear long sleeves and pants when outdoors and apply insect repellant with DEET.

* Repair broken screens on doors and windows to prevent mosquitoes from getting indoors.

Report all dead birds by calling 1-877-WNV-BIRD.