Invasive Mosquito – USA

An invasive mosquito species, the yellow fever mosquito, has been spotted in San Joaquin County, California. 

It is a small black and white mosquito that bites aggressively during the day. The public can help prevent the spread of these invasive mosquitoes by calling in daytime-biting mosquitoes to the district.

The district will continue surveillance efforts by placing traps used to collect adult mosquitoes and mosquito eggs. Additional efforts may include the district’s staff conducting door-to-door inspections of the residential area near the Brookside area of Stockton.

The mosquito can be recognized by white markings on its legs and a marking in the form of a lyre on the upper surface of its thorax. This mosquito originated in Africa, but is now found in tropical, subtropical and temperate regions throughout the world.

Photo: Aedes aegypti or yellow fever mosquito.

The species are a threat because they can transmit numerous diseases like Zika virus, and dengue fever virus.

It is not native to California. It has become established in some areas of southern and central California. Since 2019, it was found in San Joaquin, Stanislaus, Sacramento, and Placer counties.

The public’s help is crucial in controlling the spread of this mosquito population. It lays its eggs just above the water line in small containers and vessels that hold water, such as dishes under potted plants, birdbaths, ornamental fountains, tin cans, or discarded tires.

Residents should inspect around their yard and outside their homes and dump out even the smallest amount of standing water. Be sure to clean and scrub bird baths and pet watering dishes weekly and dump the water from overflow dishes under potted plants. Also, remove any unnecessary containers and trash around properties.

Residents experiencing mosquito bites during the day should report them immediately to San Joaquin County Mosquito & Vector Control District at (209) 982-4675 or 1-800-300-4675.

Additional information can be found at San Joaquin County Mosquito & Vector Control District’s website, or the California Department of Public Health website.

Follow us

While you are here, help us with

Access to Essential Drugs

One third of children, women and men have no access to essential medicines, putting lives at risk. Hospitals frequently run out of medicines and other essential supplies. Our Med-Aid program connects hospitals with aid and ensures that they receive exactly what they need.

Access to Diagnostics

Much of today’s innovation is either not reaching or not suitable for people in developing countries.

Data to Improve Health

Faster and reactive systems to help provide lifesaving support to vulnerable communities.

Support our work. It only takes a minute but makes a world of difference!

With your help we can bring modern diagnostics and essential medicines to people in need, track disease outbreaks better and help prevent future pandemics.