First 2015 Detection of New Invasive Mosquito

County of San Diego environmental health officials have confirmed the discovery of another Aedes aegypti mosquito, a day-feeding invader that can carry serious diseases and was found here for the first time last year.

County officials urged people to empty standing water inside and outside their homes to keep mosquitoes from breeding.

The newly discovered mosquito was found in an office in Chula Vista, near the areas where Aedes mosquitoes were first found in October, at Naval Base San Diego and a residence.

The Aedes aegypti mosquito, also known as the yellow fever mosquito, can carry serious diseases. However, those diseases — including yellow fever, dengue fever and chikungunya — are not native to San Diego County and are rarely seen here unless travelers contract them elsewhere and return home. There hasn’t been an outbreak of yellow fever in the U.S. in more than 100 years.

Despite that, environmental and public health officials are working to keep the mosquito from becoming established here because it can transmit those and other diseases. With the new discovery, the County has found a total of nine adult mosquitoes and two larvae sources since October.

The Aedes mosquito is fairly easy to identify. That’s because it differs from most native San Diego County mosquitoes in several important ways:

  • It usually feeds during the day and is an aggressive biter. Most native mosquitoes prefer to feed between dusk and dawn.
  • It likes to live in urban areas — feeding and laying eggs not only outside, but inside people’s homes in almost anything that can contain water, including plant saucers, cups and flowerpots.
  • It is small and black with white stripes.

“The main thing people should remember is to look for and eliminate any standing water that these mosquitoes could use as a breeding source,” said County Environmental Health Director Elizabeth Pozzebon. “And again, that includes inside your home. These mosquitoes will breed indoors.”

County vector control teams have been putting up and monitoring traps for the Aedes mosquito.

Officials said the public should remember to follow the general “Prevent, Protect, Report” mosquito-fighting message they’ve used for the County’s “Fight the Bite” West Nile virus prevention campaign.

Prevent Mosquito Breeding: Dump out or remove any backyard or indoor item that can hold water, such as plant saucers, rain gutters, buckets, garbage cans, toys, old tires, and wheelbarrows. Mosquito fish, available for free, may be used to control mosquito breeding in backyard water sources such as unused swimming pools, ponds, fountains and horse troughs.

Protect Yourself from Mosquito Bites: Protect yourself from mosquito bites that can transmit disease. Wear long sleeves and pants when outdoors. Use insect repellent containing DEET, picaridin, oil of lemon eucalyptus or IR3535 when outside. Make sure screens on windows and doors are in good condition and secured to keep insects out.

Report Green Swimming Pools and Mosquitoes Biting During the Day Indoors: Report incidents of neglected swimming pools or areas of standing water that could be mosquito breeding areas — and mosquitoes biting indoors during daylight hours — to the Vector Control Program at (858) 694-2888 or vector@sdcounty.ca.gov.

For more information about County Vector Control, go to the program’s website.



Gig Conaughton is a communications specialist with the County of San Diego Communications Office. Contact