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Residents encouraged to dump standing water; West Nile virus detected in bird from Menlo Park



Contact: Rachel Curtis-Robles, PhD

Public Health Education and Outreach Officer



Residents encouraged to dump standing water to reduce mosquito populations

Burlingame, CA (May 15, 2024) - As the weather warms, San Mateo County Mosquito and Vector Control District is reminding people to dump standing water to prevent mosquito problems around their homes. The District recently detected West Nile virus in a dead American crow collected from Menlo Park.

Mosquitoes are a nuisance, but can also carry diseases like West Nile virus. After California experienced very high West Nile virus activity in 2023, District staff are concerned that this year could be another long mosquito season. A wet winter created additional habitats for mosquitoes to develop, and the remaining stagnant water can create breeding locations for disease-spreading mosquitoes. District staff routinely inspect and treat mosquito breeding sources throughout the County, and residents should check their yards for potential breeding sources as well.

“Dumping standing water is one of the most effective ways to prevent mosquitoes from breeding around your home,” said Rachel Curtis-Robles, Public Health Education and Outreach Officer for the District. “Even small amounts of water – as small as a bottle cap full of water – can produce mosquitoes. It’s important to check around your yard and dump water to prevent mosquitoes.”

It only takes a small amount of water to produce mosquitoes, so following these simple steps can reduce the risk of mosquitoes and the diseases they transmit:

  • Eliminate standing water at least once a week, including in flowerpots and saucers, old tires, buckets, pet dishes, and trash cans. Mosquitoes can lay their eggs in very small amounts of standing water.
  • When outside and mosquitoes are active, apply insect repellent containing an active ingredient registered with the Environmental Protection Agency – such as DEET, picaridin, oil of lemon eucalyptus, or IR3535 – according to label instructions. 
  • Wear long sleeves and pants, especially if outside at dawn and dusk when mosquitoes are most active.
  • Install screens on windows and doors, and keep them in good repair to keep mosquitoes out of your home.
  • Clean rain gutters clogged with leaves.
  • Report dead birds to the statewide West Nile Virus Call Center by phone at 1-877-WNV-BIRD (1-877-968-2473) or online. Not all birds can be collected for testing, but all reports help the District identify potential risk areas for West Nile virus. 

If you are being bitten by mosquitoes while on your property, request a visit from District staff. For assistance with a mosquito problem in San Mateo County, contact the District at 650­­-344-8592. For more information about West Nile virus and District services, go to the District’s website at



About the San Mateo County Mosquito & Vector Control District: We are an independent special government district that is focused on protecting the public health of the residents of San Mateo County through a science-based program of integrated vector management that is responsive to the community. The District delivers specific services to residents and businesses under the guidance of a Board of Trustees comprising representatives from each of the 20 cities in San Mateo County and the County Board of Supervisors.





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