Horses

Horse Potomac Horse Fever: Recognition and Prevention

Potomac horse fever is a serious rickettsial infection causing severe colic and laminitis risk, requiring rapid recognition and treatment.

Key Facts

Potomac horse fever is caused by Neorickettsia risticii transmitted via flukes in aquatic insects
Peak incidence is late summer in regions near rivers and streams
Signs include fever, depression, reduced gut sounds, and profuse watery diarrhea
Laminitis is a serious secondary complication in many affected horses
Mortality rates without treatment can reach 30%; oxytetracycline is effective
Vaccines are available but provide partial protection due to strain variation

Welfare Considerations

Affected horses suffer significant pain from colic and diarrhea, with the added risk of debilitating laminitis. Rapid veterinary intervention dramatically improves outcomes. Welfare-focused management includes early antibiotic treatment, supportive fluids, anti-endotoxin therapy, and proactive laminitis prevention with deep bedding and pain management.

What You Can Do

Vaccinate horses in endemic areas annually before peak season
Keep horses away from streams and areas with aquatic insect activity during summer
Call a vet immediately if fever, reduced gut sounds, or diarrhea appear
Request oxytetracycline treatment promptly - early treatment is critical
Apply deep sand or shavings bedding proactively to support feet
Monitor for laminitis signs for 2-3 weeks after recovery