A serological survey on equine influenza in Ahvaz

Equine influenza is an acute، infectious and highly contagious respiratory disease with worldwide distribution and high morbidity and low mortality. The disease caused by H7N7 and H3N8 subtypes of genus (type) A of influenza virus. The most significant clinical signs of this disease are fever، coughing and nasal discharge. In this study، the presence of antibody against two subtypes of equine influenza virus was studied in 100 horses in Ahvaz region with HI test. Blood samples were collected from January to July 2005. Horses divided to two sexes and three age groups (less than 2 years، 2-10 years and more than 10 years old). The results of this study showed that only two stallion (8 and 16 years old) have had antibodies against subtype of H3N8. The antibody titer in these two cases were 1/64. It was suggested that antibody presence in these two horses due to infection of influenza virus، because the vaccination do not perform in this region.