A review on epidemiology and ecology of west nile fever: An emerging arboviral disease

Abstract

West Nile virus (WNV) is found in 26 provinces of Iran in humans, horses, and birds. Due to lack of vaccines, the only method to reduce the risk of the disease in communities is to increase people’s awareness. Lack of killing and overhunting of animals does not alter the infected-blood transmission from animals to humans by mosquito bites, but can reduce disease transmission risks including the transmission of West Nile fever (WNF) to humans. WNV is an enveloped Flavivirus that in nature has an enzootic cycle between mosquitoes and birds. The virus has occasional epizootic spillover causing disease in humans and horses. WNV-transmitting mosquitoes are widespread around the world, and the geographical range of transmission and the disease has increased over the past seven decades. Most human infections with WNV are asymptomatic, but severe neurological disease may develop resulting in long-term complications or death. Given the increasing trend of reported human WNF cases, it is necessary to implement surveillance programs and increase awareness of people and health staff about the function of biological factors including carnivores in the hunting of infected animals and collecting their carcass from nature. Hunting and killing of birds and dogs living near humans increase both the risk of deviation of blood-feeding of the zoophilic mosquitoes to humans and the outbreak of the disease.

Keywords

• epidemiology; west nile fever; arbovirus; iran