Weekly Disease Roundup: September 14 – September 21, 2026
As of September 21, 2026, Equine Alert recorded 22 new disease alerts across 15 states over the past week, led by West Nile Virus.
This Week at a Glance
| Metric | This Week | Last Week | Change |
|---|---|---|---|
| Total Alerts | 22 | 28 | -21% |
| States Affected | 15 | — | — |
| Diseases Reported | 5 | — | — |
Activity by Disease
| Disease | Alerts |
|---|---|
| West Nile Virus | 14 |
| Vesicular Stomatitis | 3 |
| Strangles | 3 |
| New World Screwworm | 1 |
| Equine Protozoal Myeloencephalopathy | 1 |
Activity by State
| State | Alerts | Primary Disease |
|---|---|---|
| Colorado | 3 | Vesicular Stomatitis |
| Pennsylvania | 3 | West Nile Virus |
| Michigan | 2 | West Nile Virus |
| California | 2 | West Nile Virus |
| Idaho | 2 | West Nile Virus |
| New Mexico | 1 | New World Screwworm |
| Washington | 1 | West Nile Virus |
| Kentucky | 1 | West Nile Virus |
| Kansas | 1 | Strangles |
| Tennessee | 1 | West Nile Virus |
| New York | 1 | West Nile Virus |
| Wisconsin | 1 | Strangles |
| Wyoming | 1 | West Nile Virus |
| Arkansas | 1 | West Nile Virus |
| Florida | 1 | Strangles |
This Week's Alerts
- September 18 | Vesicular Stomatitis | La Plata, Colorado — resolved
- September 18 | Vesicular Stomatitis | Archuleta, Colorado — resolved
- September 18 | New World Screwworm | Grant, New Mexico
- September 18 | Vesicular Stomatitis | Delta and Montezuma, Colorado — official quarantine
- September 18 | West Nile Virus | Franklin, Washington
- September 18 | West Nile Virus | Washington, Kentucky
- September 17 | West Nile Virus | Lancaster, Pennsylvania
- September 17 | Strangles | Douglas, Kansas — voluntary quarantine
- September 17 | West Nile Virus | Dauphin, Pennsylvania
- September 17 | West Nile Virus | Muskegon, Michigan
- September 17 | West Nile Virus | Kent, Michigan
- September 17 | West Nile Virus | MicMinn, Tennessee
- September 17 | West Nile Virus | Amador, California
- September 17 | West Nile Virus | Union, Pennsylvania
- September 16 | West Nile Virus | Lawrence, New York
- September 16 | West Nile Virus | Minidoka, Idaho
- September 16 | Equine Protozoal Myeloencephalopathy | Minidoka, Idaho
- September 16 | Strangles | Pierce, Wisconsin — voluntary quarantine
- September 16 | West Nile Virus | Shasta, California
- September 16 | West Nile Virus | Uinta, Wyoming
- September 15 | West Nile Virus | Garland, Arkansas
- September 14 | Strangles | Sarasota, Florida
Protect Your Horses
Disease activity shifts week to week. A few habits go a long way:
- Check destination states for disease activity before you travel or compete
- Isolate returning horses for 14–21 days when possible
- Monitor temperatures daily — fever is often the first sign of EHV-1
- Avoid nose-to-nose contact and don't share water buckets or equipment at events
- Inspect wounds daily and keep them clean and covered
Want alerts the moment a new outbreak is reported in your state? Sign up for free email alerts or explore the interactive outbreak map. Data sourced from the Equine Disease Communication Center (EDCC).