Horse Vaccination Schedule and Core Vaccines Explained [2026]

Vaccinations are essential for protecting your horse from dangerous and potentially fatal diseases. Understanding which vaccines your horse needs—and when—is a fundamental part of horse ownership.

Why Vaccinations Matter

Vaccines protect against diseases that can be:

• Fatal (rabies, Eastern/Western encephalomyelitis)
• Severely debilitating (tetanus, strangles)
• Highly contagious (influenza, rhinopneumonitis)
• Required by law or for travel (rabies, some states)

Core Vaccines: Every Horse Needs These

The American Association of Equine Practitioners (AAEP) recommends these core vaccines for ALL horses:

1. Tetanus

• What it is: Bacterial toxin from soil contamination of wounds
• Why critical: Nearly always fatal without treatment
• Schedule: Annual booster (or after injury if over 6 months)

2. Eastern/Western Equine Encephalomyelitis (EEE/WEE)

• What it is: Mosquito-borne viral brain infection
• Why critical: 90% fatality for EEE, 50% for WEE
• Schedule: Annual (twice yearly in high-risk areas)

3. West Nile Virus

• What it is: Mosquito-borne neurological disease
• Why critical: 30% fatality, many survivors have lasting issues
• Schedule: Annual (twice yearly in high mosquito areas)

4. Rabies

• What it is: Fatal viral disease from infected animals
• Why critical: 100% fatal, zoonotic (can spread to humans)
• Schedule: Annual

Risk-Based Vaccines

These depend on your horse’s exposure risk:

Influenza (Flu)

• Risk factors: Shows, travel, new horses, boarding
• Schedule: Every 6 months for high-risk horses
• Notes: Similar to human flu—spreads rapidly

Rhinopneumonitis (EHV-1/EHV-4)

• Risk factors: Shows, pregnant mares, young horses
• Schedule: Every 6 months; pregnant mares at 5, 7, 9 months
• Notes: Can cause abortion in mares, neurological disease

Strangles

• Risk factors: Contact with many horses, boarding facilities
• Schedule: Annual for high-risk horses
• Notes: Highly contagious bacterial infection; intranasal or injectable

Potomac Horse Fever

• Risk factors: Near rivers/streams, endemic areas
• Schedule: Annual or twice yearly in endemic areas
• Notes: Geographic specific

Botulism

• Risk factors: Round bale feeding, endemic areas
• Schedule: Annual in endemic regions
• Notes: Fatal paralytic disease

Vaccination Schedule

Vaccination Costs

Typical annual cost: $150-300 for basic protocol

Young Horse Vaccination Schedule

Foals

• 4-6 months: First series of core vaccines
• 5-7 months: Booster (4-6 weeks after first)
• 6-8 months: Third dose (4-6 weeks after second)
• 12 months: Annual boosters begin

Note: Foals from unvaccinated mares may need different timing.

Pregnant Mare Vaccinations

• EHV-1 (Rhinopneumonitis): At 5, 7, and 9 months of pregnancy
• Core vaccines: 4-6 weeks before foaling
• Rationale: Antibodies pass to foal through colostrum

Possible Side Effects

Normal Reactions

• Mild swelling at injection site
• Slight stiffness for 24-48 hours
• Low-grade fever
• Mild lethargy

When to Call the Vet

• High fever (over 102°F)
• Severe swelling
• Hives or allergic reaction
• Difficulty breathing
• Collapse or severe weakness

Self-Administering vs. Vet

Vet-Only (Required)

• Rabies (legal requirement in most states)
• Intranasal strangles

Can Self-Administer

• Core vaccines (if experienced)
• Flu/Rhino

Reasons to Use a Vet

• Proper storage of vaccines
• Correct administration technique
• Handle reactions immediately
• Documentation for travel/shows

The Bottom Line

Core vaccines (tetanus, EEE/WEE, West Nile, rabies) are non-negotiable for every horse. Risk-based vaccines depend on your horse’s lifestyle and geographic location. Work with your veterinarian to develop a vaccination protocol appropriate for your horse. The $150-300 annual investment in vaccines is far less than treating any of these serious diseases.

Sources: American Association of Equine Practitioners, USDA, American Veterinary Medical Association