Yellow Fever Mosquitoes Discovered in Orange County

San Clemente Times

The Orange County Mosquito and Vector Control District  is urging residents to report tiny black and white, day-biting mosquitoes. On April 21st, OCMVCD responded to complaints of day biting mosquitoes in the City of Anaheim. A thorough investigation was conducted and the presence of yellow fever mosquitoes (Aedes aegypti) was confirmed. The yellow fever mosquito can transmit dengue fever, chikungunya and yellow fever.

“We immediately mobilized our staff upon the discovery of Aedes aegypti in the Anaheim residence,” said Larry Shaw, Director of Operations. “OCMVCD has expanded surveillance efforts for this type of mosquito. We are conducting door-to-door inspections of properties for mosquito breeding and standing water in surrounding neighborhoods. 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 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 small artificial or natural containers that hold water around the home such as indoor plants, vases and flower pots, or tree cavities.

Aedes aegypti is not native to Orange County. This tropical and subtropical mosquito now found worldwide was first identified in California’s central valley and central coast in June of 2013, and last year in Los Angeles County.

Determining the origin of the yellow fever mosquito is difficult, a release from the district said. 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 being bitten by mosquitoes during the day. Call 949.654.2421.
• Dump and drain all stagnant water around homes. 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.

No other yellow fever mosquitoes have been discovered in the surrounding neighborhood.

For more information, contact the Orange County Mosquito and Vector Control District at

949.654.2421, or visit www.ocvcd.org.