Total Positive Counties: 39
| County | Human Cases | Dead Birds | Mosquito Samples | Sentinel Chickens | Horses |
| State Totals | 442 | 1352 | 3528 | 343 | 0 |
| Alameda | - | 11 | 2 | - | - |
| Alpine | - | - | - | - | - |
| Amador | 1 | - | - | - | - |
| Butte | 21 | 22 | 48 | 38 | - |
| Calaveras | - | - | - | - | - |
| Colusa | 2 | - | - | 9 | - |
| Contra Costa | 4 | 33 | 11 | 5 | - |
| Del Norte | - | - | - | - | - |
| El Dorado | 1 | 4 | - | - | - |
| Fresno | 14 | 6 | 185 | - | - |
| Glenn | 6 | 4 | 11 | 10 | - |
| Humboldt | - | - | - | - | - |
| Imperial | - | - | 1 | - | - |
| Inyo | - | - | - | - | - |
| Kern | 17 | - | 80 | - | - |
| Kings | 8 | 4 | 118 | - | - |
| Lake | 1 | 5 | 39 | 5 | - |
| Lassen | - | - | - | - | - |
| Los Angeles | 151 | 124 | 436 | 126 | - |
| Madera | 6 | 5 | 101 | - | - |
| Marin | - | 5 | - | - | - |
| Mariposa | - | - | - | - | - |
| Mendocino | - | - | - | - | - |
| Merced | - | 5 | 13 | 35 | - |
| Modoc | - | - | - | - | - |
| Mono | - | - | - | - | - |
| Monterey | 1 | - | - | - | - |
| Napa | - | 1 | 4 | - | - |
| Nevada | - | 2 | - | 1 | - |
| Orange | 32 | 91 | 444 | - | - |
| Placer | 7 | 30 | 103 | 7 | - |
| Plumas | - | - | - | - | - |
| Riverside | 11 | 16 | 32 | - | - |
| Sacramento | 25 | 411 | 455 | 3 | - |
| San Benito | - | - | - | - | - |
| San Bernardino | 8 | 5 | 82 | 23 | - |
| San Diego | 20 | 264 | 99 | 9 | - |
| San Francisco | - | - | - | - | - |
| San Joaquin | 13 | 37 | 350 | - | - |
| San Luis Obispo | - | - | - | - | - |
| San Mateo | - | 15 | 5 | - | - |
| Santa Barbara | - | - | - | - | - |
| Santa Clara | 1 | 89 | 13 | 1 | - |
| Santa Cruz | - | 2 | 3 | - | - |
| Shasta | 1 | 3 | 12 | 3 | - |
| Sierra | - | - | - | - | - |
| Siskiyou | - | - | - | - | - |
| Solano | 4 | 13 | 16 | 10 | - |
| Sonoma | - | 8 | 2 | - | - |
| Stanislaus | 26 | 14 | 258 | - | - |
| Sutter | 12 | 10 | 68 | 33 | - |
| Tehama | 5 | - | - | 8 | - |
| Trinity | - | - | - | - | - |
| Tulare | 10 | 3 | 260 | - | - |
| Tuolumne | - | - | - | - | - |
| Ventura | 7 | 34 | - | - | - |
| Yolo | 16 | 72 | 259 | 4 | - |
| Yuba | 11 | 4 | 18 | 13 | - |
| State Totals | 442 | 1352 | 3528 | 343 | 0 |