Rapid international travel and trade results in the importation of both pathogens and vectors not found in California. The Asian tiger mosquito, Aedes albopictus and the yellow fever mosquito, Aedes aegypti, for example, has been introduced into North America in used vehicle tires, and has become established in some areas of southern California. These species can develop in artificial containers in warmer areas. Currently both species are established in some areas of southern California. The Aedes aegypti is established in Fresno, Clovis, Madera County and in 2017, Merced County. In August of 2019 and July 11 of 2020, San Joaquin County Mosquito and Vector Control District's surveillance system found Aedes aegypti in west Stockton. In 2021, A. aegypti were found in west Stockton, Ripon and Escalon. For 2022, the District found this invasive species in south Stockton and Manteca. The District is working to reduce the population of this invasive species, which proves to be a difficult task. Community participation is pertinent to eliminating this mosquito. When this mosquito is found, staff inspects neighborhoods door to door, working to remove mosquito development sources. Residents are asked to remove all standing water around their properties. It is also important to remove any unnecessary items from yards that can hold as little as a tablespoon of water. See map for up to date information.
For more information on invasive Aedes, a.k.a. daytime biting mosquitoes, click here. Please see the District's brochure: Invasive Aedes Mosquitoes
These species are efficient vectors of Zika, dengue, chikungunya and yellow fever. Other potential diseases of concern include Japanese encephalitis, Rift Valley fever, Venezuelan encephalitis and malaria. These viruses are currently not known to be transmitted by mosquitoes in San Joaquin County or California. Report daytime biting mosquitoes to the District at (209) 982-4675.
Aedes aegypti or Yellow Fever mosquito is a small, dark mosquito with stripes forming a harp shape on the mid-body (thorax) and white banded legs. They usually will approach low and behind a person, often biting people's ankles and elbow areas.
Aedes albopictus or Asian Tiger Mosquito is a small black mosquito with a bright white stripe on the front of the mid-body (thorax) and bright white banded legs. This mosquito is an aggressive, rapid daytime biter.
For in-depth information on these mosquito-borne diseases, please see the following links:
California Department of Public Health - Zika
Centers for Disease Control and Prevention - Zika
* References from: The Biology and Control of Mosquitoes in California. 1996. Mosquito and Vector Control Association of California. Elk Grove, CA., CDPH and Best Management Practices for Mosquito Control in California, 2012, CDPH
or online at westnile.ca.gov
Sign up to receive email updates including news releases and spray updates.