VENTURA, California – Mosquito season has arrived in Ventura County. The Ventura County Environmental Health Division and Ventura County Public Health (VCPH) is encouraging residents to eliminate standing water now to prevent mosquito breeding and reduce the chances of being bitten by mosquitoes.
In addition to native mosquito species, some of which can transmit West Nile Virus (WNV), the invasive Aedes aegypti mosquito has become established in Ventura County and continues to spread since first being detected in Simi Valley in 2020. Most recently, Aedes aegypti was confirmed for the first time in the City of Santa Paula during routine surveillance following reports of mosquito activity.
Aedes aegypti mosquitoes are aggressive biters during the day and will also bite at night. They can breed in as little as a teaspoon of water and have evolved to survive and thrive in and around our homes. Aedes aegypti has the potential to transmit several viruses such as dengue, chikungunya, Zika, and yellow fever. In 2024, 18 cases of local dengue transmission occurred in California. While no local transmission has occurred in Ventura County, the presence of this mosquito means an infected traveler returning to or visiting the area could be a source of local transmission.
The most effective way to control mosquitoes is to prevent them from breeding. Aedes aegypti mosquitoes lay eggs just above the water line, and these eggs can remain viable for over a year or more without water. It is important to discard, alter, or store any objects that can collect water to prevent mosquito breeding.
Common breeding sites include yard and street drains, potted plants, saucers, buckets, toys, tarps, and other outdoor containers. The best way to reduce mosquito populations on your property is to regularly check for and eliminate standing water.
Aedes aegypti mosquitoes often bite indoors. The Ventura County Environmental Health Division and Ventura County Public Health strongly encourage residents to take the following precautions to protect themselves and their families:
- Ensure doors and windows are closed or have tight-fitting screens with no holes
- When mosquitoes are present wear long sleeves and pants
- Use an EPA-approved insect repellent containing DEET, picaridin, oil of lemon eucalyptus, para-menthane-diol (PMD), or 2-undecanone
Residents can:
- Report mosquito activity and standing water sources by calling the Mosquito Complaint HOTLINE at 805-658-4310 or filing a report online at https://eco.vcrma.org.
- Request mosquito-eating fish for ornamental ponds and water features by calling 805-662-6582.
- Report dead birds for West Nile Virus testing by calling the California Department of Public Health at 877-WNV-BIRD (877-968-2473) or visiting https://westnile.ca.gov.
For more information about mosquito prevention and control in Ventura County, visit:
