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Environmental Health

Helpful Links

San Francisco Health Code:

Article 1 Section 37

Article 2 Section 92

Article 11 Section 609

Vector Control Rules and Regs (pdf)

SFDPH Fee Schedule

Other Websites

US EPA Mosquito Control

CA Mosquito & Vector Control Association

CA West Nile

US CDC West Nile

CA Department of Pesticide Regulation

Related Documents

Taking Action Against Mosquitoes (pdf in English)

  • Chinese (pdf)
  • Russian (pdf)
  • Spanish (pdf)
  • Tagalog (pdf)
    Related SFDPH Programs

    Vector Control

    Mosquito Control

    West Nile Virus

    Rodent Control

    Pigeon Nuisances

    Program Contact

    Luisa Garfil
    Office: (415) 252-3800
    Fax: (415) 252-3930

    Mosquito Control -- Trapping and Monitoring


    What type of mosquito traps will the Healthy Housing Program's Vector Control use?

    Mosquito TrapWe will use standard CO2 traps that consist of a 9 inch canister, a fan that hangs below the canister, and a funnel shaped net on the bottom. The whole apparatus hangs about 3 feet from a stable structure or tree in your yard.

    How does the trap work?

    The canister is filled with dry ice that would provide the CO2 source that will attract the mosquito. There is also a very small light that will also help attract mosquitoes. When mosquitoes get close enough to the trap, the fan blows the mosquitoes into the net and keeps them there until the trap is picked up the following day.

    Are the traps safe?

    Yes. The dry ice is contained in an insulated plastic canister with a tight lid. The dry ice will not come in contact with anything unless the lid is forced open. The fan is about 4 inches in diameter, low power, and harmless. There is also a label on the canister with a city seal that informs people as to the purpose of the apparatus and a caution note reminding people not to open the trap.

    How long are the traps set for?

    Ideally, we would like to set the traps in the afternoon and pick them up in the morning of the following day.

    I do not have mosquitoes or standing water on my property. Would you still be interested in setting a trap on my property?

    Yes. Traps will tell us if there is mosquito activity in your neighborhood, not necessarily coming from your property. If you have no mosquito sources on your property, the traps could at least tell us if there is a source close by.

    Is mosquito trapping really important?

    Absolutely. Mosquitoes are the number one disease-causing vectors in the world, let alone the annoyances they cause. But as important as mosquitoes are, the solutions to eliminating sources are easy and generally inexpensive provided the sources are located. Monitoring helps us find the source(s). Once a source is found, the Vector Control Technicians will work with property owners and managers to offer simple methods to either eliminate the source or render it not habitable to mosquitoes.

    How will information obtained from trapping be used?

    Ideally, we would like to set traps across several properties in a neighborhood. The specimens will be collected the following day and identified as to species, gender, and number of mosquitoes per trap. Male mosquitoes would indicate that the source is close by. The type of mosquito would suggest types of preferred water sources, and the number could point the direction of the source(s). We may set additional traps clustered around the high counts if we are not able to locate the source the first time.



    Making a Complaint

    The Environmental Health Branch (EHB) certified vector technicians and the City's pest control contractor investigate all reports of mosquito activity. When filing a complaint, provide information specifying when biting is occurring (daytime or night time, or both) and whether the biting or mosquitos are observed indoors or outdoors. This information helps us determine what type of mosquito is affecting the area and what the best response should be.

    The Environmental Health Branch investigates complaints about standing water and other conditions that may allow mosquito breeding.

    For complaints about these issues call or visit 311 to have your complaint recorded and routed correctly to Environmental Health.