Total Positive Counties: 49
| County | Human Cases | Dead Birds | Mosquito Samples | Sentinel Chickens | Horses |
| State Totals | 445 | 2569 | 2003 | 585 | 32 |
| Alameda | 1 | 12 | 1 | - | - |
| Alpine | - | - | - | - | - |
| Amador | - | 3 | - | - | - |
| Butte | 6 | 38 | 5 | 31 | - |
| Calaveras | 1 | 1 | 1 | 9 | - |
| Colusa | 1 | 3 | - | 1 | - |
| Contra Costa | 4 | 88 | 31 | 15 | 3 |
| Del Norte | - | 1 | - | - | - |
| El Dorado | 1 | 9 | - | - | - |
| Fresno | 3 | 44 | 53 | 24 | 1 |
| Glenn | 1 | 17 | 1 | 5 | - |
| Humboldt | - | 1 | - | - | - |
| Imperial | - | - | 7 | 26 | - |
| Inyo | - | - | - | - | - |
| Kern | 2 | 10 | 7 | 18 | - |
| Kings | 2 | 1 | - | 1 | - |
| Lake | - | 2 | 3 | 1 | 1 |
| Lassen | - | - | 1 | - | - |
| Los Angeles | 156 | 481 | 517 | 134 | - |
| Madera | - | 3 | 1 | 2 | - |
| Marin | - | 1 | - | - | - |
| Mariposa | - | - | - | - | - |
| Mendocino | - | 1 | - | - | - |
| Merced | 1 | 5 | - | 3 | 1 |
| Modoc | - | 1 | - | - | - |
| Mono | - | 2 | - | - | - |
| Monterey | - | 6 | - | - | - |
| Napa | - | 1 | - | - | - |
| Nevada | - | 5 | - | - | - |
| Orange | 71 | 639 | 361 | 3 | 2 |
| Placer | 6 | 4 | 27 | 11 | 1 |
| Plumas | - | - | - | - | - |
| Riverside | 62 | 39 | 118 | 118 | 9 |
| Sacramento | 13 | 130 | 277 | 7 | 3 |
| San Benito | - | - | - | - | - |
| San Bernardino | 36 | 176 | 170 | 61 | 2 |
| San Diego | 35 | 567 | 40 | 15 | 4 |
| San Francisco | - | - | - | - | - |
| San Joaquin | 12 | 69 | 207 | 18 | - |
| San Luis Obispo | - | 2 | - | - | - |
| San Mateo | - | 2 | - | - | - |
| Santa Barbara | 1 | 1 | - | - | - |
| Santa Clara | 1 | 13 | 1 | - | - |
| Santa Cruz | - | 3 | - | - | - |
| Shasta | 1 | 7 | - | 3 | - |
| Sierra | - | - | - | - | - |
| Siskiyou | - | - | - | - | - |
| Solano | 1 | 7 | 1 | 7 | - |
| Sonoma | - | 11 | 2 | - | - |
| Stanislaus | 17 | 45 | 75 | 38 | 2 |
| Sutter | - | 2 | 12 | 9 | - |
| Tehama | 4 | 6 | - | - | - |
| Trinity | - | 1 | - | - | - |
| Tulare | 5 | 76 | 64 | 20 | 1 |
| Tuolumne | - | - | - | - | - |
| Ventura | - | 24 | - | 4 | 1 |
| Yolo | 1 | 9 | 19 | - | 1 |
| Yuba | - | - | 1 | 1 | - |
| State Totals | 445 | 2569 | 2003 | 585 | 32 |