An invasive, non-native mosquito known to carry diseases and not seen in Contra Costa County in two years has been found in North Concord.
The Contra Costa Mosquito and Vector Control District said it recently found an Aedes aegypti mosquito in a trap, the first since the district found some in Martinez two years ago.
Aedes aegypti is commonly known as the yellow fever mosquito, which can transmit pathogens that cause dengue fever, Zika virus, and chikungunya.
The district said in a statement that the mosquito is very stealth-like, flying low to the ground, and has been called an “ankle biter’ as these mosquitoes commonly bite people on the leg below the knee.
The latest discovery was made in one of the district’s traps that are set regularly in North Concord. The district has continued to set traps in Martinez; but no additional invasive mosquitoes have been found in that area for two years.
“We found this mosquito in one of our routine West Nile virus surveillance traps, which shows that our surveillance system is working,” said Steve Schutz, the district’s scientific programs manager. “Additional trapping and inspections are being carried out in the area to determine the extent of the infestation and prevent it from spreading.”
District employees will be going door-to-door in the surrounding North Concord area, looking for signs of the mosquitoes to stop them before the population can expand to other communities.
Aedes aegypti mosquitoes were first introduced to Southern California more than 10 years ago. They are now established in 24 counties across the state.
These mosquitoes lay sticky eggs that can be transported to new areas easily. The district said to reduce the risk, it’s important to dump out any amount of standing water in front and backyards and scrub the inside of the containers to remove any sticky mosquito eggs.
To reduce the risk of mosquito bites, residents are encouraged to use an EPA-registered insect repellent containing active ingredients like DEET, picaridin, the repellent version of oil of lemon eucalyptus, or IR3535.
People should also check window screens to make sure they fit properly without any gaps or rips in the screen.
County residents who experience day-biting mosquitoes should contact the district and request mosquito service by calling (925) 685-9301 or at https://contracosta.leateamapps.com/#/public/servicerequest.
Signing up for district notifications allows county residents to receive information on West Nile virus activity and adult mosquito control operations in real time. Subscribe at https://www.contracostamosquito.com/subscribe.