Total Positive Counties: 42
| County | Human Cases | Dead Birds | Mosquito Samples | Sentinel Chickens | Horses |
| State Totals | 176 | 1102 | 2379 | 404 | 10 |
| Alameda | - | 13 | - | - | - |
| Alpine | - | - | - | - | - |
| Amador | - | - | - | - | - |
| Butte | 19 | 42 | 32 | 54 | - |
| Calaveras | - | - | - | - | - |
| Colusa | 2 | 1 | - | 8 | - |
| Contra Costa | 3 | 64 | 13 | 6 | 1 |
| Del Norte | - | - | - | - | - |
| El Dorado | 1 | - | - | - | - |
| Fresno | 3 | 10 | 64 | - | - |
| Glenn | 7 | 8 | 16 | 9 | - |
| Humboldt | - | 1 | - | - | - |
| Imperial | - | - | - | - | - |
| Inyo | - | - | - | - | - |
| Kern | 10 | 2 | 179 | 12 | 1 |
| Kings | - | 10 | 75 | - | - |
| Lake | - | 10 | 61 | 5 | - |
| Lassen | - | - | - | - | - |
| Los Angeles | 71 | 302 | 372 | 115 | - |
| Madera | - | 7 | 15 | 2 | - |
| Marin | 2 | 6 | - | 1 | - |
| Mariposa | - | - | - | - | - |
| Mendocino | - | 2 | - | - | - |
| Merced | - | 35 | 8 | 18 | - |
| Modoc | - | - | - | - | - |
| Mono | - | - | - | - | - |
| Monterey | - | - | - | - | - |
| Napa | 1 | 2 | - | - | - |
| Nevada | - | 6 | - | 2 | - |
| Orange | 3 | 29 | 30 | - | - |
| Placer | 4 | 29 | 89 | 12 | 1 |
| Plumas | - | - | - | - | - |
| Riverside | 12 | 18 | 79 | 33 | 1 |
| Sacramento | 3 | 165 | 377 | 5 | 3 |
| San Benito | - | - | - | - | 1 |
| San Bernardino | 2 | 31 | 209 | 20 | - |
| San Diego | - | 6 | - | - | - |
| San Francisco | 1 | - | - | - | - |
| San Joaquin | 5 | 33 | 158 | - | - |
| San Luis Obispo | - | 1 | 1 | - | - |
| San Mateo | - | - | - | - | - |
| Santa Barbara | - | - | - | - | - |
| Santa Clara | 1 | 49 | 25 | 2 | - |
| Santa Cruz | - | 1 | 1 | - | - |
| Shasta | - | 34 | 15 | 14 | - |
| Sierra | - | - | - | - | - |
| Siskiyou | - | - | - | - | - |
| Solano | 1 | 15 | 1 | 11 | - |
| Sonoma | - | 17 | 5 | 1 | - |
| Stanislaus | 8 | 13 | 145 | 8 | 2 |
| Sutter | 7 | 16 | 61 | 33 | - |
| Tehama | - | 3 | - | 8 | - |
| Trinity | - | 1 | - | - | - |
| Tulare | 1 | 6 | 90 | 4 | - |
| Tuolumne | - | 1 | - | - | - |
| Ventura | 1 | 8 | - | - | - |
| Yolo | 4 | 94 | 244 | 10 | - |
| Yuba | 4 | 11 | 14 | 11 | - |
| State Totals | 176 | 1102 | 2379 | 404 | 10 |