Preventing Contagious Diseases in Horses by a Vet – 2025 Biosecurity & Testing Guide 🐴🧼
In this article
Preventing Contagious Diseases in Horses by a Vet – 2025 Biosecurity & Testing Guide 🐴🧼
By Dr Duncan Houston, BVSc
Introduction
In 2025, with frequent horse travel, shows, and shared boarding barns, preventing contagious equine diseases is more important than ever. Diseases like strangles and influenza can devastate herds quickly—especially if silent carriers go undetected. In this vet-led guide, learn how to use quarantine, testing, and targeted treatment to protect your horses and stable community year-round.
1. Quarantine Protocol: The 3-Week Rule 📆
- All new arrivals should be isolated from resident horses for 21 days
- Monitor temperature twice daily to catch early signs of infection (fever ≥ 101.5°F)
- Use separate feed/water buckets, grooming tools, and handlers
2. Coggins Test for Equine Infectious Anemia (EIA) 🧪
- Required for horse travel and entry into most barns
- Current negative Coggins test (within 6–12 months) should be required for all new horses
- EIA has no treatment or vaccine—positive horses must be quarantined for life or euthanized
3. Strangles: Silent Threat in Healthy Horses 🤧
Strangles is caused by Streptococcus equi—a highly contagious bacterium. While infected horses show fever, nasal discharge, and swollen lymph nodes, some horses carry and shed the bacteria silently.
Testing for Strangles:
- Use a PCR test and culture from a nasopharyngeal wash or guttural pouch sample
- Asymptomatic “carriers” must be isolated and treated
Treating Carrier Horses:
- Bacteria often hide in guttural pouches (throat structures)
- Guttural pouches can be flushed and infused with penicillin to eliminate the bacteria
- Retest until two negative PCRs confirm clearance
4. Influenza: Fast-Spreading Viral Infection 💨
- Highly contagious respiratory virus—especially among young and travel-active horses
- Short incubation means most infected horses show signs within a week
- 3-week quarantine for new horses typically prevents outbreaks
Preventive Measures Summary 🛡️
| Action | Why It Matters |
|---|---|
| 3-week quarantine | Captures most contagious periods for respiratory diseases |
| Daily temp checks | Fever often precedes visible illness |
| Coggins test | Protects against untreatable EIA |
| Strangles PCR test | Detects silent carriers before exposure |
| Guttural pouch flush | Eliminates hidden strangles bacteria in carriers |
Case Example: Stable Saved by Pre-Arrival Testing
- A new show gelding arrived at a Texas boarding barn
- Quarantined and tested for strangles—PCR was positive despite no symptoms
- Guttural pouches flushed and treated; follow-up tests negative
- Horse joined herd safely—no outbreak occurred
FAQs About Contagious Disease Prevention
Q: What if the horse has a vaccine record but no strangles test?
A: Vaccination reduces severity but doesn’t prevent shedding—testing is still needed in group settings.
Q: Can a horse spread strangles without symptoms?
A: Yes—some horses become silent carriers and shed from their guttural pouches.
Q: How long does it take to clear a carrier?
A: With treatment and guttural pouch flushing, clearance often takes 1–2 weeks followed by repeat testing.
Conclusion
Preventing contagious diseases like strangles and influenza in 2025 requires more than just vaccines. A 3-week quarantine, Coggins confirmation, and strangles PCR testing are now considered best practices—especially in busy boarding barns or show circuits. Although it takes effort, these protocols can prevent serious outbreaks and keep your herd healthy.
Need help designing a biosecurity plan or performing carrier testing? Visit AskAVet.com or download the app 📱 to speak directly with Dr Duncan Houston for barn-specific disease prevention support. 🩺🐴
