A: Residents can sign up for treatment notifications occurring in their zip code: https://www.sgvmosquito.org/sign-up-for-e-alerts.

A: Mosquito control treatments effectively reduce the mosquito population which decreases the risk of disease transmission to residents. Decisions to make area-wide mosquito treatments from backpacks, trucks, helicopters, or airplanes are based on predetermined thresholds and data collected through mosquito trap counts and testing of adult mosquitoes for the presence of disease-causing viruses. 

To view the current treatment schedule in the San Gabriel Valley, visit: www.PublicHealthMosquito.org.

A: Emails are sent to residents subscribed to the eAlerts in the affected area. To subscribe: (https://www.sgvmosquito.org/sign-up-for-e-alerts).

Online notifications are posted on “Area-Wide Treatments page on our website https://www.sgvmosquito.org/public-health-response-area-wide-mosquito-treatments

Please note: Treatment events can be canceled or rescheduled due to weather conditions, operational delays, or other unforeseen reasons.

A: Controlling mosquito larvae: Mosquitoes grow in large and small areas containing stagnant water. Stagnant water containing eggs, larval, and pupal mosquitoes are called sources. Larvicides reduce the overall mosquito population by preventing larvae from maturing into adult, biting mosquitoes. Larval control of mosquitoes is the backbone of most mosquito control programs in California. Many larvicides used in treatments are based on natural compounds known to stop growth or quickly kill mosquito larvae. These treatments can be applied directly to a water source or by equipment distributing a low volume application of pesticides. Treatments can be applied from backpacks, trucks, helicopters, or airplanes. 

Controlling adult mosquitoes: Adulticides are products used when it is important to rapidly reduce adult mosquito populations to reduce the risk of disease transmission to people. The most common method of adulticiding is ultra-low volume (ULV) spraying. These droplets float on the air currents and quickly eliminate mosquitoes that come into contact with the droplets. Treatments can be applied from backpacks, trucks, helicopters, or airplanes. 

A: The decision to conduct a treatment for larval and adult mosquitoes is based on trap-counts or when disease surveillance finds a significant threat of disease transmission in an area. Truck-mounted and aerial treatments happen when there are many sources spread across a large area.

Chemical control is used for immature mosquitoes in water when biological control (mosquitofish) and source reduction is not plausible or effective.

Chemical control for adult mosquitoes is necessary when biological and physical control methods are unable to maintain mosquito numbers below a level that is considered tolerable, or when emergency control measures are needed to rapidly disrupt and reduce the transmission of disease to humans.

All products are registered with the US Environmental Protection Agency (EPA) and are applied by trained and state-certified San Gabriel Valley Mosquito and Vector Control District technicians.

A. Mosquito control products do not pose a risk to you or your family for several reasons: They are applied at very low levels (2 tablespoons or less per acre) and they have undergone extensive toxicity research before being approved for use. Fact: Some head lice control products contain an active ingredient that is often used in adult mosquito control products. These products are safely applied directly to a person’s head at a much higher concentration compared to the exposure level for a mosquito control treatment. 

For more information on insecticides and public health, consult the U.S. Environmental Protection Agency, which oversees the registration of these chemicals. The National Pesticide Information Center (NPIC) and the Centers for Disease Control and Prevention also post their mosquito control resources online.

For treatment schedule including locations see our Area-wide Mosquito Treatments page at: www.PublicHealthMosquito.org.

A. If you are experiencing health problems for any reason, it is important to see your health care provider promptly.

A: No. The District uses public health pesticides approved by the US EPA for treatments on and over outdoor residential and recreational areas. The treatment will dissipate from the treated area and degrade quickly in sunlight. In some instances, mosquito control backpack treatments may leave wet surfaces. Allow them to dry before touching or handling.

A: The District uses mosquito control products in strict accordance with the law and label recommendations and are not harmful to pets. The most commonly used products used to control mosquitoes are the same found in flea and tick control products. However, to reduce your pet’s exposure, keep them inside during treatment applications.

A: It is not necessary to close doors or windows. The treatment will dissipate from the treated area and degrade quickly in sunlight. 

A: Your swimming pool water and items found in your yard will not be affected.

As you normally would, wash your vegetables and fruit before you eat them.

A: Nighttime adult mosquito control treatment using ULV applications at the label rates should have no impacts on bees sheltering in hives. In some instances, our agency must apply adult mosquito control products during the day. If a daytime application is necessary, applicators are trained to avoid blooming plants, beehives, or other areas where bees may congregate.

A: Whole house air conditioning units cool recirculated air drawn from inside your house and can be left running during and after mosquito control treatments. The same is true for window and wall units running on cooling settings. They do not draw air from outside and can be left running. However, window or wall air-conditioning units running on the fan setting should be turned off to avoid pulling in air from the outside.

A: Questions concerning specific insecticides can be directed to the U.S. Environmental Protection Agency, responsible for the registration of insecticides. 

Many questions are addressed on the EPA’s Mosquito Control Web site.

The National Pesticide Information Center (NPIC) provides insecticide information and answers to questions regarding insecticide use and human health. Call toll-free: 1-800-858-7378. NPIC is cooperatively sponsored by Oregon State University and the U.S. Environmental Protection Agency.

The Center for Disease Control and Prevention provides guidance and planning resources online.