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08.26.16: Neighborhood Treatments Scheduled in San Gabriel Valley to Control Invasive Aedes Mosquitoes

San Gabriel Valley, August 26, 2016

In an ongoing effort to control Aedes albopictus (tiger mosquitoes) the San Gabriel Valley Mosquito and Vector Control District will conduct truck-mounted fogging in the early morning on Wednesday, August 31, 2016 in a small area of El Monte.  The focus of the treatments is to reduce increasing larval and adult populations of Aedes albopictus. This mosquito is an aggressive day biter capable of transmitting several serious viral diseases including Zika, chikungunya, and dengue.

The treatments will cover an area of El Monte west of (and including) Parkway Dr., north of (and including) Klingerman St., east of (and including) Cogswell Rd., and south of (and including) Valley Blvd. The treatment area is based on recent surveillance data and the likelihood of reducing the population of mosquitoes.   The actual streets and properties that will be treated within this zone may be adjusted as data are received between now and the treatment day. These adjustments will be posted within the treatment zone 24-48 hours prior to treatments. 

The District will begin treatments on the morning of Wednesday, August 31, 2016 at approximately 3:00 a.m. and conclude by 6:00 a.m.  This time window was chosen to avoid traffic and outdoor pedestrian activity as well as maximize favorable weather conditions. An alternate date of Thursday, September 1, 2016 may be used in case of conditions that are not favorable for an effective treatment.  

Two different products shall be applied which target immature (larvicide) and adult (adulticide) Aedes albopictus.  The larvicide, VectoBac®WDG will be applied by a truck-mounted fogger as a low volume mist. The active ingredient in VectoBac®WDG is Bacillus thuringiensis israelensis (Bti).  This product is specific for mosquitoes, with no known risk to humans and wildlife when applied according to the label.  Additional information about this product can be found at:

The adulticide AquaDUET™ will be applied by a truck-mounted fogger as an ultra-low volume mist. The active ingredients are Prallethrin, Sumithrin®and piperonyl butoxide. Additional information about this product can be found at:


The signal word on the U.S. Environmental Protection Agency (EPA)-approved label for AquaDUET™ is CAUTION, which indicates that it is-slightly toxic with minimal potential risk to people.  Residents are not required to take any special precautions, however are advised to remain indoors with doors and windows shut during the treatment period. 

AquaDUET™ may be toxic to fish and aquatic insects.  The District recommends that residents cover fish ponds during the application to prevent possible deposition of droplets.  Outdoor pet food and water bowls should be moved indoors or covered during the treatment.  The product breaks down rapidly in sunlight and will not leave a residue. 

The San Gabriel Valley Mosquito and Vector Control District is committed to managing Aedes albopictus, which is an invasive species capable of transmitting several diseases that endanger public health.    Applying pesticides by truck is one more tool vector control districts can use to target this mosquito.  

What can residents do about invasive Aedes mosquitoes?

Mosquitoes lay their eggs and grow in standing water. Invasive Aedes are “container breeders” and lay eggs along the waterline of water-filled containers or on the stems of aquatic plants. Any item on your property that holds water, no matter how small will grow mosquitoes. Common sources include flower vases, plant saucers, buckets, used tires, and plants that hold water like “lucky bamboo” and bromeliads. Residents should inspect their property regularly, looking for and eliminating standing water.  The eggs of invasive Aedes are extremely durable and can stay dormant in dry containers for months waiting for the right conditions to hatch. For this reason containers that have been left outside for a while should be scrubbed down with a brush and warm soapy water before being thrown away or stored in a dry place.  

Throughout the summer, basic protective measures should be followed:

  • Wear mosquito repellent and protective clothing when outdoors while mosquitoes are active.
  • Regularly inspect property to identify and remove sources of standing water where mosquitoes lay their eggs and grow.
  • Ensure doors and windows are properly screened.
  • Report increased mosquito activity, sources of standing water, and green pools to the District at (626) 814-9466 or online at

Residents living in the City of El Monte are encouraged to call the San Gabriel Valley Mosquito and Vector Control District at (626) 814-9466 with any questions or to report mosquito activity.  For more information, also visit