The California Department of Public Health makes a weekly summary of human Zika activity available at their website. As of October 2016, California mosquitoes have not transmitted Zika virus to humans. Among the statistics, the page indicates California total number of human infections, the number of sexual transmissions, the number of Zika infections in pregnant women and the number of liveborn infants with Zika related birth defects. The page can be viewed here.
California Zika Summary Available Online