Total Positive Counties: 42
| County | Human Cases | Dead Birds | Mosquito Samples | Sentinel Chickens | Horses |
| State Totals | 297 | 1210 | 2507 | 478 | 11 |
| Alameda | - | 18 | - | - | - |
| Alpine | - | - | - | - | - |
| Amador | - | - | - | - | - |
| Butte | 23 | 42 | 33 | 57 | - |
| Calaveras | - | - | - | - | - |
| Colusa | 2 | 1 | - | 8 | - |
| Contra Costa | 4 | 68 | 13 | 7 | 1 |
| Del Norte | - | - | - | - | - |
| El Dorado | 1 | - | - | - | - |
| Fresno | 5 | 11 | 66 | - | - |
| Glenn | 8 | 8 | 16 | 9 | - |
| Humboldt | - | 1 | - | - | - |
| Imperial | - | - | - | - | - |
| Inyo | - | - | - | - | - |
| Kern | 20 | 2 | 181 | 12 | 2 |
| Kings | - | 12 | 78 | - | - |
| Lake | - | 10 | 61 | 6 | - |
| Lassen | - | - | - | - | - |
| Los Angeles | 121 | 307 | 411 | 147 | - |
| Madera | 3 | 7 | 16 | 2 | - |
| Marin | 2 | 7 | - | 1 | - |
| Mariposa | - | - | - | - | - |
| Mendocino | - | 2 | - | - | - |
| Merced | - | 39 | 8 | 21 | - |
| Modoc | - | - | - | - | - |
| Mono | - | - | - | - | - |
| Monterey | - | - | - | - | - |
| Napa | 1 | 2 | - | - | - |
| Nevada | - | 6 | - | 2 | - |
| Orange | 4 | 37 | 47 | - | - |
| Placer | 5 | 38 | 89 | 13 | 1 |
| Plumas | - | - | - | - | - |
| Riverside | 31 | 22 | 80 | 43 | 1 |
| Sacramento | 3 | 177 | 384 | 6 | 3 |
| San Benito | - | - | - | 1 | 1 |
| San Bernardino | 9 | 37 | 237 | 29 | - |
| San Diego | - | 6 | - | - | - |
| San Francisco | 1 | - | - | - | - |
| San Joaquin | 6 | 34 | 163 | - | - |
| San Luis Obispo | - | 1 | 1 | - | - |
| San Mateo | - | - | - | - | - |
| Santa Barbara | - | - | - | - | - |
| Santa Clara | 2 | 65 | 25 | 2 | - |
| Santa Cruz | - | 1 | 1 | - | - |
| Shasta | 1 | 37 | 15 | 21 | - |
| Sierra | - | - | - | - | - |
| Siskiyou | - | - | - | - | - |
| Solano | 1 | 15 | 1 | 12 | - |
| Sonoma | - | 33 | 5 | 1 | - |
| Stanislaus | 16 | 13 | 158 | 8 | 2 |
| Sutter | 10 | 16 | 61 | 35 | - |
| Tehama | - | 3 | - | 8 | - |
| Trinity | - | 1 | - | - | - |
| Tulare | 4 | 7 | 97 | 5 | - |
| Tuolumne | - | 1 | - | - | - |
| Ventura | 2 | 8 | - | - | - |
| Yolo | 6 | 104 | 246 | 11 | - |
| Yuba | 6 | 11 | 14 | 11 | - |
| State Totals | 297 | 1210 | 2507 | 478 | 11 |