A survey on equine herpes virus-4 infection in horses of Khuzestan province

Equine Herpesvirus type 4 (EHV-4) is one of the most important world-wide distributions of equine herpes viruses. This virus mainly causes respiratory diseases in this animal. The present study attempted to determine the existence of this virus among the horse population of Khuzestan province. One hundred fifty-one horses kept in a number of clubs in different cities of the province were sampled and they were tested by applying PCR. The data were analyzed using SPSS version 16 to administer the Chi-square test, logistic regression, Mann-Whitney test and Fisher’s Exact test and the degree of freedom was set on α = 0.05. The results of the study showed that the overall rate of infection with EHV-4 in horses was 16/56% disregarding the host and environmental factors. The results also indicated that age, gender, pregnancy status, history of respiratory diseases, and the history of displacement between the cities of Khuzestan province and the exit from the province did not have a significant effect on the amount of infection (P>0.05). At the same time, the rate of infection of horses in Ahvaz was higher than that of other cities (Shooshtar, Shoosh, Ramhormoz and Mahshahr), but this difference turned out to be significant only in relation to Ramhormoz (lowest infection rate) (P<0.05). The results of the study showed that although the positive cases reported in this study were far lower compared to the previous studies using the ELISA method, the existence of the virus in the horses of the province remained significant.