Total Positive Counties: 40
| County | Human Cases | Dead Birds | Mosquito Samples | Sentinel Chickens | Horses |
| State Totals | 801 | 2442 | 3340 | 443 | 0 |
| Alameda | 1 | 96 | 16 | 1 | - |
| Alpine | - | - | - | - | - |
| Amador | - | - | - | - | - |
| Butte | 24 | 22 | 40 | 37 | - |
| Calaveras | - | - | - | - | - |
| Colusa | 3 | 4 | 1 | 9 | - |
| Contra Costa | 5 | 44 | 25 | 15 | - |
| Del Norte | - | - | - | - | - |
| El Dorado | - | 7 | - | - | - |
| Fresno | 43 | 9 | 138 | - | - |
| Glenn | 10 | 4 | 8 | 9 | - |
| Humboldt | - | 2 | - | - | - |
| Imperial | 1 | - | - | - | - |
| Inyo | - | - | - | - | - |
| Kern | 11 | 3 | 111 | - | - |
| Kings | 4 | 3 | 150 | - | - |
| Lake | 1 | 18 | 71 | 5 | - |
| Lassen | - | - | - | - | - |
| Los Angeles | 253 | 99 | 356 | 146 | - |
| Madera | 3 | 5 | 37 | - | - |
| Marin | - | 6 | 3 | - | - |
| Mariposa | - | - | - | - | - |
| Mendocino | 1 | - | - | - | - |
| Merced | 1 | 8 | 11 | 11 | - |
| Modoc | - | - | - | - | - |
| Mono | - | - | - | - | - |
| Monterey | - | - | - | - | - |
| Napa | - | 12 | - | - | - |
| Nevada | - | - | - | 2 | - |
| Orange | 263 | 431 | 499 | - | - |
| Placer | 7 | 40 | 77 | - | - |
| Plumas | - | - | - | - | - |
| Riverside | 14 | 1 | 91 | 43 | - |
| Sacramento | 10 | 294 | 487 | 10 | - |
| San Benito | - | - | - | - | - |
| San Bernardino | 21 | 17 | 97 | 32 | - |
| San Diego | 11 | 39 | 1 | 2 | - |
| San Francisco | - | - | - | - | - |
| San Joaquin | 9 | 53 | 239 | - | - |
| San Luis Obispo | - | - | - | - | - |
| San Mateo | - | 21 | 15 | - | - |
| Santa Barbara | - | 2 | - | - | - |
| Santa Clara | 10 | 925 | 30 | 5 | - |
| Santa Cruz | - | 1 | - | - | - |
| Shasta | 2 | 6 | 33 | 12 | - |
| Sierra | - | - | - | - | - |
| Siskiyou | - | - | - | - | - |
| Solano | 5 | 33 | 11 | 23 | - |
| Sonoma | - | 37 | 9 | 3 | - |
| Stanislaus | 33 | 47 | 176 | 12 | - |
| Sutter | 8 | 19 | 52 | 31 | - |
| Tehama | 4 | - | - | 13 | - |
| Trinity | - | - | - | - | - |
| Tulare | 21 | 40 | 311 | 4 | - |
| Tuolumne | - | - | - | - | - |
| Ventura | 1 | 7 | - | - | - |
| Yolo | 15 | 71 | 221 | 9 | - |
| Yuba | 6 | 16 | 24 | 9 | - |
| State Totals | 801 | 2442 | 3340 | 443 | 0 |