Page 639 - The Veterinary Care of the Horse

EQUINE INFLUENZA

VetBooks.ir Equine influenza (flu) is a disease that affects the upper and lower respiratory tract of horses,

donkeys and mules. It is caused by several strains of the equine influenza virus. The disease
is very infectious and spreads rapidly through groups of horses. The incubation period is 1–5

days. People cannot be infected with equine flu.

Clinical signs

These may include:
• a temperature of 39–41 °C (103–106 °F) which lasts for 1–3 days

• a harsh, dry cough that can last for 2–3 weeks

• a clear, watery nasal discharge that may become thick and yellow or green (Figure 15.3)

• enlarged glands under the lower jaw
• clear, watery discharge from the eyes

• depression

• loss of appetite

• oedema of the lower limbs

• sore muscles and stiffness.