Inyo County Public Health Officials Identify Mosquito Pool Positive for St. Louis Encephalitis
PUBLIC HEALTH OFFICIALS IDENTIFY MOSQUITO POOL POSITIVE FOR ST. LOUIS ENCEPHALITIS
INYO COUNTY- The Owens Valley Mosquito Abatement Program and Inyo County Public Health Department announced today that a local mosquito pool has tested positive for Saint Louis Encephalitis (SLE). The mosquito pool was identified north of the city of Bishop in the vicinity of Williams Creek and the Bishop Canal. The sample was collected on August 15th and results were received late yesterday, August 16th. This is the first positive mosquito pool for SLE identified in Inyo County this year.
“Mosquito populations are extremely high due to the massive runoff and water spreading activities this year, which increases the risk of mosquito-borne diseases. These diseases can be serious, so it is important that individuals protect themselves from mosquito bites,” stated Nate Reade Inyo/ Mono Ag. Commissioner.
The Owens Valley Mosquito Abatement Program has approximately 20 mosquito traps placed in strategic areas throughout the county, mostly within close vicinity of city limits. The traps are checked every week and mosquito pools are collected weekly. “Our agency will continue monitoring disease activity and treat affected areas,” said Robert Miller, Program Supervisor of the Owens Valley Mosquito Abatement Program. “Although the positive mosquitoes were collected in a specific area, all county residents should take precautions, like wearing insect repellent and minimizing outdoor activity at dusk and dawn, when mosquitoes are most active.”
Symptoms of Saint Louis Encephalitis (SLE) include fever, headache, nausea, vomiting, and tiredness. Severe neuroinvasive disease (often involving encephalitis, an inflammation of the brain) is more common in older adults. The severe version of the disease is very dangerous and can even be fatal. There are no vaccines to prevent nor medications to treat SLE.
SLE is transmitted to humans through the bite of an infected mosquito. Mosquitoes become infected when they feed on infected birds. Individuals can reduce their risk of mosquito-borne diseases by taking the following precautions:
- Limit time outdoors during dawn and early evening.
- When outdoors, wear loose-fitting, light-colored, long-sleeved shirts and pants when mosquitoes are most active (during dusk and dawn).
- Apply insect repellent that contains DEET, Picaridin, or oil of lemon eucalyptus according to label instructions to prevent mosquito bites.
- Make sure that doors and windows have tight-fitting screens. Repair or replace screens that have tears or holes.
- Eliminate all sources of standing water on your property that can support mosquito breeding by:
- Draining or eliminating, old tires, buckets, plastic covers, toys, or any other container where mosquitos can breed.
- Emptying and changing the water in birdbaths, fountains, wading pools, rain barrels, and potted plant trays at least once a week to destroy potential mosquito habitats.
- Draining or filling temporary pools of water with dirt. – Keeping swimming pool water treated and circulating.
- Contact Mosquito Control if there is a significant mosquito problem where you live or work.
If you think you or anyone in your household has symptoms that are causing you concern, contact your healthcare provider.
The United States Environmental Protection Agency (EPA) has a useful search tool that the public can use to find the repellent products most appropriate for them and their families. The tool is available at https://www.epa.gov/insect-repellents/find-repellentright-you.
For additional information related to Saint Louis Encephalitis, please visit the California Department of Public Health Department’s website: https://www.cdph.ca.gov/Programs/CID/DCDC/Pages/SLE.asp
Please report any mosquito problems to the Owens Valley Mosquito Abatement Program by calling (760) 873-7853 or visiting inyomonoagriculture.com.
Visit us on our Facebook page at https://www.facebook.com/OVMAP/ to get the latest information about mosquitoes in the Owens Valley.

