Skip to main content

Residential Irrigation is a Big Contributor to Mosquito-borne Disease Threats

Press release published by the Mosquito and Vector Control Association of California 

Sacramento, June 20, 2019 – Rainwater isn't the only worry for mosquito control officials; wasteful water practices are creating mosquito breeding grounds in backyards across California. Overwatering - or inefficient watering - of lawns and using excessive water to wash cars and driveways can create standing water where mosquitoes lay eggs. Unattended standing water in pet bowls and flowerpots can also create more urban mosquitoes which means greater risk of disease transmission in residential areas.

In addition, abandoned swimming pools, ornamental ponds, septic tanks, and rain barrels, which are especially predominant in areas ravaged by wildfires, can contribute to mosquito breeding. Mosquitoes can breed in sources of water as small as a bottle cap, so it’s critical that residents inspect their yards weekly and remove any standing water.

Summer is a time to enjoy the outdoors, but it is also the height of mosquito season.
Jeremy Wittie, President of Mosquito and Vector Control Association of California

“Summer is a time to enjoy the outdoors, but it is also the height of mosquito season,” said Jeremy Wittie, President of the Mosquito and Vector Control Association of California (MVCAC). “Protecting public health is a shared responsibility and we must all commit to making mosquito prevention part of our regular routine. Responsible irrigation as well as dumping and draining all standing water in the yard are simple steps residents can take to eliminate mosquito habitats.”

West Nile virus is the leading cause of mosquito-borne disease in the U.S. and last year in California West Nile virus activity was detected in 41 counties, resulting in 217 human infections and 11 deaths. As the weather heats up this year, the California Department of Public Health reports increased West Nile virus activity particularly in the Southern California region where unprecedented numbers of West Nile virus-positive mosquito samples have been reported. There are no vaccines for people against West Nile virus and other mosquito-transmitted viruses, such as St. Louis encephalitis and chikungunya, all of which are costly to treat and can have long-term health and financial consequences.

National Mosquito Control Awareness Week, June 23-29, 2019, is an important way to raise awareness and educate residents about the public health threat mosquitoes pose to our communities.

Residents are encouraged to integrate mosquito control into their daily lives and take preventative measures to minimize exposure to mosquito bites:

1. Apply insect repellent containing EPA-registered active ingredients, including DEET, picaridin, oil of lemon eucalyptus (or PMD), or IR3535 on exposed skin and clothing according to label instructions. Repellents keep mosquitoes from biting. DEET can be used safely on infants and children 2 months of age and older.

2. Dress in long sleeves and pants especially if outside at dawn and dusk when mosquitoes that can spread West Nile virus are most active.

3. Install screens on windows and doors and keep them in good repair.

4. Eliminate all sources of standing water on your property, including in flowerpots, old tires, and buckets.

5. Repair leaking faucets and broken sprinklers.

6. Clean rain gutters clogged with leaves.

7. Report neglected swimming pools and mosquitoes to your local mosquito and vector control agency.

8. Maintain irrigation systems to avoid excess water use and runoff into storm drains.

In addition to educating the public about how to prevent mosquitoes and protect themselves from mosquito bites, mosquito experts are working to ensure there are adequate local, state and federal resources to meet the increasing challenges of combating mosquito-borne diseases.

At the federal level, MVCAC has been advocating for final adoption and funding for the Strengthening Mosquito Abatement Safety and Health Act which would authorize U.S. Centers for Disease Control and Prevention (CDC) resources to be used to protect public health by addressing emerging infectious mosquito-borne diseases and improving existing mosquito control programs.

In California, MVCAC is sponsoring legislation, AB 320 (Quirk), to put in state statute the CalSurv Gateway, a statewide vector-borne disease surveillance system, that provides tools for real-time data collection, visualization, and analysis. The CalSurv Gateway is a critical system that tracks disease-spreading mosquitoes – where they are, where they’ve been, where they may be heading, and where new diseases might be emerging.

For additional information on mosquitoes and mosquito-borne diseases visit the California Department of Public Health.


To increase awareness and enforce prevention and control programs statewide, the Mosquito and Vector Control Association of California (MVCAC) provides support to more than 65 districts throughout California. As a result, approximately half the land area and 85 percent of California’s population are within the boundaries of a mosquito control program. MVCAC represents special districts, other subdivisions of local government, and the state of California which are responsible for mosquito and vector control, surveillance of West Nile virus and other vector-borne diseases, as well as public education programs to help Californians protect themselves from disease. MVCAC advocates safe, effective, and environmentally friendly methods of mosquito and vector control.