Infectious diseases include a wide range of bacterial, viral, fungal, and parasitic illnesses that can affect equine health, performance, and herd biosecurity. Common concerns are equine influenza, equine herpesvirus (EHV-1/4), strangles (Streptococcus equi), West Nile virus, West Nile and equine encephalitides, equine infectious anemia (EIA), and various bacterial or fungal respiratory and wound infections. Prevention emphasizes vaccination tailored to risk and travel, strict biosecurity for new arrivals or sick horses, routine deworming based on fecal egg counts, and prompt isolation and testing of suspected cases. Early recognition—fever, nasal discharge, coughing, lymph node swelling, neurologic signs, lethargy, or poor appetite—allows timely diagnostics (PCR, culture, serology) and targeted treatment (antivirals when indicated, appropriate antibiotics, supportive care, anti-inflammatories, and wound management). Herd health planning, including vaccination schedules, quarantine protocols, and rapid communication with trainers and owners, reduces spread and protects individual and group health.
