IMPERIAL COUNTY- The Imperial County Public Health Department announced today that multiple local mosquito pools have tested positive for Saint Louis Encephalitis (SLE). The mosquito pools were identified in the vicinity of Orchard Road in Holtville and La Paz Drive and Cannon Drive in Imperial. The samples were collected on July 15th, and results were received today, July 18th.   

“While it’s not unusual to detect mosquito activity during the summer months, the identification of multiple positive pools in different areas is a reminder for all of us to stay alert,” stated Stephen Munday, M.D., Health Officer. “We want residents to take precautions, like eliminating standing water and using insect repellent, to help reduce the risk of mosquito-borne illness and protect their families and communities.”

The Public Health Department’s Vector Control Program maintains approximately 52 mosquito traps throughout the county, primarily within city limits. Traps are checked several times a week, and mosquito pools are tested weekly.

“Vector Control staff remain actively engaged in surveillance and mitigation efforts throughout the county,” said Jeff Lamoure, Deputy Director of Environmental Health. “We encourage the public to be part of the solution by reporting mosquito problems and taking simple steps at home to reduce breeding sources.”

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. There are no vaccines to prevent or 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 containers where mosquitoes 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 Vector 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 the EPA website.

For additional information related to Saint Louis Encephalitis, please visit the California Department of Public Health Department’s website.