Total Positive Counties: 42
| County | Human Cases | Dead Birds | Mosquito Samples | Sentinel Chickens | Horses |
| State Totals | 479 | 1644 | 2849 | 540 | 22 |
| Alameda | 2 | 15 | - | - | - |
| Alpine | - | - | - | - | - |
| Amador | - | - | - | - | - |
| Butte | 10 | 53 | 27 | 45 | 1 |
| Calaveras | - | - | - | - | 1 |
| Colusa | 3 | 5 | - | 6 | - |
| Contra Costa | 4 | 66 | 19 | 7 | - |
| Del Norte | - | - | - | - | - |
| El Dorado | - | 5 | - | - | - |
| Fresno | 24 | 25 | 147 | - | 3 |
| Glenn | 7 | 16 | 4 | 8 | 1 |
| Humboldt | - | - | - | - | - |
| Imperial | 1 | - | 4 | 10 | - |
| Inyo | - | - | - | - | - |
| Kern | 25 | 14 | 571 | 74 | 2 |
| Kings | 3 | 2 | 102 | - | - |
| Lake | 1 | 10 | 23 | 4 | - |
| Lassen | - | - | - | - | - |
| Los Angeles | 163 | 271 | 339 | 135 | - |
| Madera | 3 | 2 | 14 | - | 1 |
| Marin | - | 1 | - | - | - |
| Mariposa | - | - | - | - | - |
| Mendocino | - | 6 | - | - | - |
| Merced | 13 | 42 | 4 | 14 | 1 |
| Modoc | - | - | - | - | - |
| Mono | - | - | - | - | - |
| Monterey | 1 | - | - | - | - |
| Napa | - | 1 | 1 | - | - |
| Nevada | - | 3 | - | - | - |
| Orange | 42 | 92 | 69 | - | - |
| Placer | 12 | 60 | 108 | 8 | - |
| Plumas | - | - | - | - | - |
| Riverside | 19 | 5 | 133 | 63 | - |
| Sacramento | 30 | 466 | 487 | 36 | 2 |
| San Benito | - | - | - | - | - |
| San Bernardino | 32 | 39 | 58 | 45 | - |
| San Diego | 1 | 1 | - | - | - |
| San Francisco | 1 | 1 | - | - | - |
| San Joaquin | 13 | 58 | 169 | - | 2 |
| San Luis Obispo | - | 1 | - | - | - |
| San Mateo | - | 5 | - | - | - |
| Santa Barbara | - | - | - | - | - |
| Santa Clara | - | 20 | 3 | - | - |
| Santa Cruz | - | 1 | - | - | - |
| Shasta | 1 | 36 | 17 | 6 | 5 |
| Sierra | - | - | - | - | - |
| Siskiyou | - | - | - | - | - |
| Solano | 2 | 28 | 3 | 2 | - |
| Sonoma | - | 8 | 3 | 1 | - |
| Stanislaus | 26 | 51 | 210 | 8 | 1 |
| Sutter | 8 | 29 | 19 | 38 | - |
| Tehama | 4 | 5 | - | - | - |
| Trinity | - | - | - | - | - |
| Tulare | 7 | 54 | 144 | 11 | - |
| Tuolumne | - | - | - | - | - |
| Ventura | 7 | 38 | 2 | 2 | - |
| Yolo | 10 | 98 | 154 | 4 | 1 |
| Yuba | 4 | 11 | 15 | 13 | 1 |
| State Totals | 479 | 1644 | 2849 | 540 | 22 |