Total Positive Counties: 42
| County | Human Cases | Dead Birds | Mosquito Samples | Sentinel Chickens | Horses |
| State Totals | 112 | 515 | 1063 | 443 | 18 |
| Alameda | - | 10 | 1 | - | - |
| Alpine | - | - | - | - | - |
| Amador | - | 1 | - | - | - |
| Butte | 2 | 13 | 5 | 36 | - |
| Calaveras | - | - | - | - | - |
| Colusa | - | 2 | - | - | - |
| Contra Costa | 5 | 45 | 17 | 13 | 1 |
| Del Norte | - | - | - | - | - |
| El Dorado | 1 | 9 | - | - | - |
| Fresno | 13 | 62 | 132 | 17 | 1 |
| Glenn | - | 6 | - | 3 | - |
| Humboldt | - | - | - | - | - |
| Imperial | - | - | 3 | 42 | - |
| Inyo | - | - | - | - | - |
| Kern | 19 | 28 | 138 | 104 | - |
| Kings | 3 | 9 | 105 | - | - |
| Lake | - | 2 | 2 | 1 | - |
| Lassen | - | - | - | - | - |
| Los Angeles | 20 | 82 | 99 | 41 | 1 |
| Madera | 1 | 11 | 3 | 7 | - |
| Marin | - | - | - | - | - |
| Mariposa | - | - | - | - | - |
| Mendocino | - | - | - | - | - |
| Merced | 4 | 9 | 11 | 14 | 3 |
| Modoc | - | 1 | - | - | - |
| Mono | - | - | 1 | - | - |
| Monterey | 1 | 4 | - | - | - |
| Napa | - | - | - | 3 | - |
| Nevada | - | - | - | - | - |
| Orange | 4 | 10 | 16 | - | - |
| Placer | - | 4 | 40 | 11 | - |
| Plumas | - | - | - | - | - |
| Riverside | 3 | 2 | 27 | 37 | 1 |
| Sacramento | - | 28 | 36 | 2 | 2 |
| San Benito | - | - | - | - | - |
| San Bernardino | 2 | 18 | 54 | 14 | - |
| San Diego | 4 | 39 | 5 | 5 | - |
| San Francisco | - | 1 | - | - | - |
| San Joaquin | 10 | 24 | 83 | 10 | 3 |
| San Luis Obispo | - | 1 | - | - | - |
| San Mateo | - | 1 | - | - | - |
| Santa Barbara | - | 1 | - | - | - |
| Santa Clara | - | 14 | 14 | - | - |
| Santa Cruz | - | 1 | - | - | - |
| Shasta | - | 9 | 2 | - | 1 |
| Sierra | - | - | - | - | - |
| Siskiyou | - | - | - | - | - |
| Solano | - | 3 | 2 | 13 | 1 |
| Sonoma | - | - | - | - | - |
| Stanislaus | 13 | 28 | 94 | 25 | 2 |
| Sutter | - | - | 25 | 11 | - |
| Tehama | - | - | - | 2 | 1 |
| Trinity | - | - | - | - | - |
| Tulare | 4 | 25 | 131 | 28 | 1 |
| Tuolumne | - | 2 | - | - | - |
| Ventura | - | 3 | - | - | - |
| Yolo | 2 | 7 | 16 | 4 | - |
| Yuba | 1 | - | 1 | - | - |
| State Totals | 112 | 515 | 1063 | 443 | 18 |