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Mosquito and Vector Surveillance 

What We Do: 

The District controls mosquitoes in the County's wetlands and other breeding sources created by standing water in street catch basins, drains, roadside ditches, flood channels, ravines and similar places on public land. Control methods include, routine larviciding operations throughout the year and when necessary treating for adults. The District works with city, county, state, and federal agencies toward permanent correction of these sources whenever it is advisable.

Mosquito Surveillance

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The District has over 100 mosquito traps placed throughout the County. The trapped mosquitoes are quantified for abundance and tested for possible diseases they could be carrying (i.e. West Nile virus, St. Louis and Western Equine Encephalitis).

Mosquito Trap
Carbon Dioxide Trap 

The Orange County Mosquito and Vector Control District uses two different types of traps: a carbon dioxide baited trap and a gravid mosquito trap.

Carbon Dioxide Baited Trap

The carbon dioxide trap is used as an attractant for recently mated females. After females mate, they need to find a blood-source to be able to produce eggs. Carbon dioxide is what all animals exhale when they are breathing so the trap mimics a potential blood-meal to the mosquito. Every time you exhale when you are outside you are attracting mosquitoes!

Gravid Mosquito Trap
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Gravid Mosquito Trap 

The gravid trap is a foul-smelling trap that egg-laying female mosquitoes are attracted to as a potential place to lay their eggs.

Other Surveillance Methods

Besides surveillance conducted by our lab every week, our inspectors are also conducting daily surveillance by looking for mosquito breeding sources in their zones. In between service requests, our Inspectors are checking drains, gutters, and ditches. Anything that can hold water for longer than one week has the potential to become a breeding source.

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