Early 1900s: The San Rafael Improvement Club is in charge of mosquito control.
1903-1905: Research on salt marsh mosquitoes was conducted in Marin County by Professor C. W. Woodworth (1903) and by Professor H. J. Quayle (1905).
May 25, 1915: California State Legislature passed the Mosquito Abatement Act. This act permitted local governments to collect revenues and form special districts to protect the public from mosquitoes and mosquito-borne diseases.
November 6, 1915: The first district in California is formed: Mosquito Abatement District No. 1; also known as the Marin Mosquito Abatement District (MAD).
1976: MAD annexed the central area of Sonoma County, becoming the Marin/Sonoma Mosquito Abatement District.
1981: District headquarters is relocated from San Rafael to Petaluma.
1982: The Town of Sonoma and its surrounding areas are annexed into the District.
1995: MAD changes its name to Marin/Sonoma Mosquito and Vector Control District (MSMVCD) to reflect the additional services now offered to the public. Those services include eradication of in-ground yellowjacket nests and provision of rodent control advice.
2000: District headquarters moves again, this time from Petaluma to the present location in Cotati.
2004: Voters approve annexation of all the unincorporated areas of Marin and Sonoma counties, forming Benefit Assessment District #2. This allows for vector control services to be made available to all residents of the two counties.
The District now services approximately 736,000 residents in a nearly 2,300 square mile service area. Each year the District responds to over 4,500 requests for service from the public.