Total Positive Counties: 42
| County | Human Cases | Dead Birds | Mosquito Samples | Sentinel Chickens | Horses |
| State Totals | 354 | 849 | 4512 | 187 | 31 |
| Alameda | 1 | 77 | 15 | 4 | - |
| Alpine | - | - | - | - | - |
| Amador | - | - | - | - | - |
| Butte | 18 | 2 | 69 | 33 | 1 |
| Calaveras | 1 | - | - | 3 | - |
| Colusa | 1 | 2 | 2 | 2 | - |
| Contra Costa | 8 | 95 | 26 | 11 | - |
| Del Norte | - | - | - | - | - |
| El Dorado | 3 | 4 | - | - | - |
| Fresno | 18 | 1 | 232 | - | 2 |
| Glenn | 4 | - | 1 | - | - |
| Humboldt | - | - | - | - | - |
| Imperial | 1 | - | 3 | - | - |
| Inyo | - | - | 2 | - | - |
| Kern | 15 | - | 107 | - | 2 |
| Kings | 9 | - | 70 | - | 1 |
| Lake | 5 | 8 | 26 | - | - |
| Lassen | - | - | - | - | - |
| Los Angeles | 42 | 44 | 576 | 30 | - |
| Madera | 9 | 1 | 207 | - | 1 |
| Marin | - | 2 | - | - | - |
| Mariposa | - | - | - | - | - |
| Mendocino | - | - | - | - | - |
| Merced | 8 | - | 43 | 22 | 2 |
| Modoc | - | - | - | - | - |
| Mono | - | - | - | - | - |
| Monterey | 1 | - | - | - | - |
| Napa | - | 4 | 7 | - | 1 |
| Nevada | 1 | 1 | - | 2 | - |
| Orange | 5 | 2 | 215 | - | 1 |
| Placer | 6 | 43 | 177 | - | 1 |
| Plumas | - | - | - | - | - |
| Riverside | 20 | 69 | 182 | - | 3 |
| Sacramento | 39 | 196 | 342 | 8 | 3 |
| San Benito | - | 1 | - | 6 | - |
| San Bernardino | 23 | 11 | 158 | - | 2 |
| San Diego | - | 9 | 1 | - | - |
| San Francisco | - | - | - | - | - |
| San Joaquin | 14 | 20 | 607 | - | 2 |
| San Luis Obispo | 2 | 1 | - | - | 2 |
| San Mateo | 2 | 14 | - | - | 1 |
| Santa Barbara | - | - | - | - | - |
| Santa Clara | 1 | 118 | 18 | - | 1 |
| Santa Cruz | - | - | - | - | - |
| Shasta | 6 | 2 | 151 | 5 | - |
| Sierra | - | - | - | - | - |
| Siskiyou | - | - | - | - | 1 |
| Solano | 6 | 18 | 24 | 11 | - |
| Sonoma | 1 | 16 | 6 | - | - |
| Stanislaus | 32 | 6 | 293 | - | 2 |
| Sutter | 7 | 6 | 66 | 19 | - |
| Tehama | - | - | - | 4 | - |
| Trinity | - | - | - | - | - |
| Tulare | 14 | 5 | 566 | 10 | 1 |
| Tuolumne | - | - | - | - | - |
| Ventura | 1 | 4 | - | - | - |
| Yolo | 25 | 67 | 294 | 10 | - |
| Yuba | 5 | - | 26 | 7 | 1 |
| State Totals | 354 | 849 | 4512 | 187 | 31 |