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West Nile virus.
Medical expert of the article
Last reviewed: 06.07.2025
West Nile fever virus is a representative of the antigen complex of Japanese encephalitis viruses. The virus has 4 genotypes.
Epidemiology of West Nile fever
The West Nile fever pathogen is common in many countries. In Russia, the disease is found in Western Siberia and the Krasnodar Territory. The reservoir and source of the virus are wild and domestic birds, mainly of the aquatic and near-aquatic ecological complex, mosquitoes and ticks. Ticks play a special role in its preservation in winter conditions. The West Nile fever virus also circulates among domestic animals. The mechanism of transmission of the virus is transmissible, the carriers are mosquitoes of the genus Culex, as well as argasid and ixodid ticks. Susceptibility in humans is high.
[ West Nile Fever Symptoms
The incubation period is 2-8 days. West Nile fever is accompanied by high fever for 3-12 days, headaches, joint pain, scarlet fever-like rash and polyadenitis. In most cases, the disease is benign. Severe cases of the disease are accompanied by the development of meningitis and encephalitis with paresis, paralysis and death. After West Nile fever, intense immunity is formed.