Aserological survey on antibodies against West Nile virus in horses of Khuzestan province

BACKGROUND: West Nile virus (WNV) is a vector-borneagent that is maintained within a bird-mosquito cycle. In humansand equids, infection by this agent is usually asymptomatic, orcharacterized by a mild febrile illness. However, fatal meningoencephalitisor encephalitis may occur. OBJECTIVES:The aim ofthis study was to evaluate the prevalence of WNVinfection andcorrelation of this organism with host and environmentaldeterminants in horses in Khuzestan province. METHODS: In2011-2012, serum samples of 155 horses were randomly collectedfrom 7 zones of Khuzestan province and were examined byELISAassay. RESULTS: Seroprevalence of WNVinfection was70.3% (95% CI: 63.1-77.5%). Statistical analysis showed thatage, zone, presence of lake, type of bed, time of sampling, stayingout of the stable after sunset and the method of insect control aresignificantly associated with infection (p0.05).CONCLUSIONS: The results of the present study confirm that theWNV infection exists in Khuzestan province. Considering thelocal weather conditions and the facility of vector-bornetransmission, the health authorities should take measures toprevent and control the infection.