The county's vector-control agency has again issued a warning that a potentially dangerous mosquito was found, this time on April 10, in the vicinity of the Holy Cross Catholic Cemetery at Santa Cruz and Avy avenues in Menlo Park.
The Aedes aegypti, a tiny black-and-white mosquito that bites during the day, can carry yellow fever, dengue fever, chikungunya (a fever) and encephalitis viruses, according to a statement from the San Mateo County Mosquito and Vector Control District.
This species has been detected at 13 locations in 2014, the first time on Jan. 22, and all near the cemetery, officials say.
This mosquito is not native to California, but has also been found in Fresno and Madera counties. There have been no reports of illness so far, and the viruses have not been detected in California, the statement says.
"Our goal is to eradicate this mosquito population," says Robert Gay, the local district manager. "We are doing everything to help ensure this mosquito does not become established in our communities."
In 1979, district agents eradicated the Aedes aegypti from San Mateo County when it was discovered near San Francisco International Airport.
The Aedes aegypti lays its eggs in water in small containers such as pots, pet bowls, bird baths and bottles. "It's important for residents to survey their yard and (areas) around their house to eliminate even the smallest amount of standing water," officials say.
To reduce the chances of being bitten, the district recommends using insect repellants containing DEET, picaridin, oil of lemon eucalyptus or IR 3535; checking window and door screens for tight fits; eliminating any standing water from around the home; wearing long-sleeved shirts and long pants; and shielding children, including through the use of mosquito nets over infant carriers, cribs and strollers.
Sources of standing water such as neglected swimming pools should be reported to the vector control district at 650-344-8592.