vector-borne disease section

CDPH Monthly Update on Number of Zika Infections in California

April 1, 2025

The following table provides the number of travel-associated infections with Zika virus in California residents during 2015 to 2025. Travel-associated infections include people exposed through travel to an area affected by Zika, or by contact with a person who recently traveled to an affected area. There have been zero locally acquired Zika infections reported in California.

Travel-associated Zika infections in California, 2015–2025 (as of April 1, 2025)

County	2015–16	2017	2018	2019	2020	2021	2022	2023	2024	2025
Total	508	126	68	43	5	2	5	3	8	1
Alameda	35	10	7	2	1	0	1	0	0	0
Butte	2	0	0	0	0	0	0	0	0	0
Contra Costa	26	4	2	3	0	0	0	0	1	1
Fresno	7	1	0	0	0	0	0	0	0	0
Humboldt	2	0	0	0	0	0	0	0	0	0
Imperial	0	1	0	0	0	0	0	0	0	0
Kern	5	1	0	0	0	0	0	0	0	0
Kings	1	0	0	0	0	0	0	0	0	0
Lake	1	0	0	0	0	0	0	0	0	0
Los Angeles	114	22	18	6	2	0	2	0	2	0
Marin	9	2	1	0	0	1	0	0	0	0
Mendocino	0	1	0	0	0	0	0	0	0	0
Merced	3	0	1	0	0	0	0	0	0	0
Monterey	5	1	0	0	0	0	0	0	0	0
Napa	3	0	0	0	0	0	0	0	0	0
Nevada	1	0	0	0	0	0	0	0	0	0
Orange	31	12	4	5	1	0	0	0	0	0
Placer	1	0	0	0	0	0	0	0	0	0
Riverside	14	4	1	2	0	0	0	1	0	0
Sacramento	7	0	0	2	0	0	0	2	0	0
San Benito	1	0	0	0	0	0	0	0	0	0
San Bernardino	18	7	0	3	0	0	0	0	0	0
San Diego	84	20	8	7	0	0	1	0	1	0
San Francisco	29	11	9	5	1	1	1	0	0	0
San Joaquin	7	1	0	0	0	0	0	0	0	0
San Luis Obispo	1	0	0	0	0	0	0	0	1	0
San Mateo	13	2	5	2	0	0	0	0	0	0
Santa Barbara	8	2	0	0	0	0	0	0	0	0
Santa Clara	36	14	8	3	0	0	0	0	2	0
Santa Cruz	3	0	0	0	0	0	0	0	0	0
Solano	3	2	1	1	0	0	0	0	0	0
Sonoma	11	5	2	1	0	0	0	0	1	0
Stanislaus	4	0	0	0	0	0	0	0	0	0
Tulare	5	2	0	0	0	0	0	0	0	0
Ventura	9	0	0	1	0	0	0	0	0	0
Yolo	6	1	1	0	0	0	0	0	0	0
Yuba	3	0	0	0	0	0	0	0	0	0