Total Positive Counties: 40
| County | Human Cases | Dead Birds | Mosquito Samples | Sentinel Chickens | Horses |
| State Totals | 97 | 586 | 2075 | 174 | 0 |
| Alameda | - | 13 | 3 | - | - |
| Alpine | - | - | - | - | - |
| Amador | - | - | - | - | - |
| Butte | 36 | 33 | 87 | 35 | - |
| Calaveras | - | - | - | - | - |
| Colusa | 1 | 3 | - | 10 | - |
| Contra Costa | - | 4 | 2 | 6 | - |
| Del Norte | - | - | - | - | - |
| El Dorado | - | 2 | - | - | - |
| Fresno | - | 1 | 64 | - | - |
| Glenn | 15 | 4 | 21 | 6 | - |
| Humboldt | - | 2 | - | - | - |
| Imperial | - | - | - | - | - |
| Inyo | - | - | - | - | - |
| Kern | 3 | 1 | 113 | - | - |
| Kings | - | 3 | 105 | - | - |
| Lake | 1 | 5 | 24 | 2 | - |
| Lassen | - | - | - | - | - |
| Los Angeles | 3 | 12 | 96 | 6 | - |
| Madera | - | 1 | 13 | - | - |
| Marin | - | 3 | - | - | - |
| Mariposa | - | - | - | - | - |
| Mendocino | 1 | - | - | - | - |
| Merced | - | 1 | 7 | 8 | - |
| Modoc | - | - | - | - | - |
| Mono | - | - | - | - | - |
| Monterey | - | - | - | - | - |
| Napa | - | 5 | - | - | - |
| Nevada | 2 | 9 | - | - | - |
| Orange | 4 | 25 | 175 | - | - |
| Placer | - | 8 | 45 | 8 | - |
| Plumas | - | - | - | - | - |
| Riverside | 6 | 39 | 120 | 3 | - |
| Sacramento | - | 62 | 108 | 1 | - |
| San Benito | - | - | - | - | - |
| San Bernardino | 3 | 7 | 140 | 12 | - |
| San Diego | 1 | 107 | 8 | - | - |
| San Francisco | - | - | - | - | - |
| San Joaquin | 1 | 11 | 151 | - | - |
| San Luis Obispo | - | - | - | - | - |
| San Mateo | - | 8 | 4 | - | - |
| Santa Barbara | - | - | 1 | - | - |
| Santa Clara | 1 | 83 | 5 | 3 | - |
| Santa Cruz | - | - | - | - | - |
| Shasta | - | 10 | 44 | 13 | - |
| Sierra | - | - | - | - | - |
| Siskiyou | 1 | - | - | - | - |
| Solano | - | 7 | 4 | 6 | - |
| Sonoma | - | 4 | 8 | - | - |
| Stanislaus | 3 | 13 | 38 | 6 | - |
| Sutter | 2 | 16 | 51 | 26 | - |
| Tehama | 3 | - | - | 7 | - |
| Trinity | - | 2 | - | - | - |
| Tulare | 4 | 22 | 463 | - | - |
| Tuolumne | - | - | - | - | - |
| Ventura | - | 6 | - | 3 | - |
| Yolo | 2 | 48 | 152 | 2 | - |
| Yuba | 4 | 6 | 23 | 11 | - |
| State Totals | 97 | 586 | 2075 | 174 | 0 |