Yellow fever mosquitoes discovered in south OC

The Orange County Mosquito and Vector Control District (OCMVCD) is urging residents to report small black-and-white mosquitoes that bite during the day, after the mosquitoes were found in Mission Viejo.
The yellow fever mosquito can transmit dengue fever, chikungunya and yellow fever.”We immediately mobilized district personnel upon the discovery of yellow fever mosquitoes at a Mission Viejo residence,” said Robert Cummings, director of technical services. “For several years, OCMVCD has expanded surveillance efforts for this type of mosquito. We are conducting neighborhood inspections of properties for mosquito breeding and standing water in the surrounding area. We are also informing nearby residents about the discovery of this invasive species and to report additional sightings and mosquito bites.”

The yellow fever mosquito has been found in the county before. An Anaheim resident in April reported day-biting mosquitoes after recognizing the mosquito from a notification. District officials say they expanded surveillance, treatments and neighborhood notifications in an effort to eradicate the invasive mosquito.  No additional yellow fever mosquitoes have been detected since the expanded control and education effort in Anaheim.

The yellow fever mosquito is recognizable by its bright silver lyre-shaped marking and white-banded legs. They can live both indoors and outdoors, and primarily bite humans. Female mosquitoes lay their eggs in containers holding as little as a teaspoon of water, and eggs, which are laid just above the water line, can survive in dry conditions for six months or more.

This tropical and subtropical mosquito now found worldwide was first identified in California’s central valley and coast two years ago and last year in Los Angeles County. Determining the origin of the yellow fever mosquito is difficult. But, it is generally accepted that the transportation of dormant eggs attached to items such as imported tires and plants is commonly associated with introductions of this mosquito species.

Once an introduction of the invasive species has occurred, residents moving materials from infested areas to non-infested areas may facilitate their spread. In order to stop the spread of this species in Orange County, OCMVCD is calling upon all residents to do their part by following these steps:

* REPORT any sightings of small black-and-white mosquitoes or if you are bit by mosquitoes during the day to 714-971-2421 or 949-654-2421.

* Dump and drain all stagnant water around your home. Eliminate plant saucers and other unnecessary containers that could be a possible breeding source.

* Clean and scrub bird baths and pet-watering dishes weekly and dump the water from overflow dishes under potted plants and flower pots.

* Do not transport or share plant stems rooted in water.

* Be sure window and door screens are in good repair to prevent mosquitoes from entering your home.

* Use insect repellent containing EPA-registered active ingredients such as DEET, Picaridin or Oil of Lemon Eucalyptus to avoid bites.

For more information, contact the Orange County Mosquito and Vector Control District at 714-971-2421 or 949-654-2421 or visit





Posted in 2015, eNews, Top-Stories.