First human case of West Nile virus found in Fresno County, second in the state
This year’s first human case of West Nile virus in Fresno County has been confirmed by health officials, just a few weeks after the season’s first mosquito carrying the disease was found in southeast Fresno.
Dr. Rais Vohra, interim health officer with the Fresno County Department of Public Health, reported Friday that an elderly man who was hospitalized was discovered to be infected with the virus. Because of patient confidentiality issues, Vohra was unable to disclose any additional information.
West Nile virus is described by the U.S. Centers for Disease Control as the leading cause of illness spread by mosquito bites. The agency also notes that there is no vaccine against West Nile, nor are there medications to treat the disease in humans.
Human cases of the virus, Vohra said, are rare, and many people who contract the virus from a mosquito experience only mild symptoms.
But West Nile encephalitis, the disease that can result, has the potential to be severe or even fatal, he said. “It’s a brain infection that can be very serious, especially in our very young and very elderly populations,” Vohra said.
Earlier Friday, California health officials reported that the first known human infection of West Nile virus in the state this year was in San Luis Obispo County, and health officials in that county reported Friday afternoon that the patient died from the disease. Last year, 233 human cases were reported statewide for the entire year.
To date, 49 infected mosquitoes have been discovered in Fresno County. That’s the highest number among all California counties. As of Friday, 177 infected mosquitoes have been discovered statewide.
Among neighboring counties in the central San Joaquin Valley, four infected mosquitoes have been found in Madera County; 28 in Tulare County; and none in Kings or Merced counties.
The discovery of the first West Nile-infected mosquito in southeast Fresno in mid-June prompted the Consolidated Mosquito Abatement District – one of several mosquito-control agencies across Fresno County – to undertake a nighttime spraying operation of mosquito-killing insecticide in the neighborhood where the insect was found, south of Belmont Avenue between Clovis and Fowler avenues.
County health officials encourage people to protect themselves from mosquitoes by:
- Applying insect repellents containing DEET, picaridin, oil of lemon eucalyptus or IR3535. Insect repellents should not be used on children under 2 months old.
- Wearing long sleeves and pants, and insect repellent, when outside during dusk and dawn hours when the mosquitoes are most active.
- Making sure windows and doors have tight-fitting screens to keep mosquitoes out of the house, and repairing or replacing screens that have holes or tears.
- Eliminating any sources of standing water where mosquitoes can lay their eggs. Dump water from flower pots, old car tires, buckets and other containers. Report abandoned or neglected swimming pools to a local mosquito abatement agency.
