Document Type : Review Article
Authors
1
Department of Pathobiology, Faculty of Veterinary Medicine, Semnan University, Semnan, Iran
2
Department of Basic Sciences, Faculty of Veterinary Medicine, Semnan University, Semnan, Iran
10.22092/ari.2025.369198.3624
Abstract
West Nile virus (WNV) is a Flavivirus transmitted by arthropods, and it is a public health concern globally. WNV was originally isolated in Uganda, and within a short period, it spread widely and caused outbreaks globally. We conducted this study to research strains from Iran, Azerbaijan, the United Arab Emirates, Pakistan, Iraq, and Turkey to understand WNV spread, genetic diversity, and evolution, and improve monitoring and control programs by evaluating the sources of introduction and modes of transmission.
A total of 93 gene sequences from Iran and neighboring countries were downloaded from the NCBI virus database. After filtering, 89 sequences were used for analysis and the construction of phylogenetic trees for several genes, alongside the genome sequences of reference lineages 1 and 2 for comparison. Sequence alignment was performed in MEGA 10 via ClustalW. Phylogenetic trees were constructed using the neighbor-joining method. Phylogenetic grouping stability was determined via the bootstrap analysis (1,000 replications).
Our analyses of the capsid, envelope protein, and NS5 genes demonstrated the importance of Iran in the circulation of WNV in the region. Although some sequences from Iran cluster with Turkish sequences, others present evidence of independent evolution. The clustering of Azerbaijani sequences with Turkish sequences and the divergence of Iraqi and Pakistani strains revealed varying degrees of connectivity and isolation. Furthermore, the hosts identified in the region include different species of mosquitoes, birds, and mammals, which were described in detail.
Our phylogenetic analysis revealed the geographical distribution of WNV transmission. The genetic diversity and connectivity of the strains provide crucial information for epidemic prediction, virus transmission, and areas that require enhanced surveillance. In the future, these evolutionary patterns will also assist in monitoring WNV transmission in Iran and its neighboring countries.
Keywords
Main Subjects
)