Representational file photo.
London: British health authorities have confirmed the first-ever detection of West Nile virus (WNV) genetic material in mosquitoes collected in the United Kingdom (UK). Officials emphasized, however, that the risk to the general public remains very low.
The positive results came from two samples of Aedes vexans mosquitoes collected by the UK Health Security Agency (UKHSA) from wetlands along the River Idle near Gamston (Retford), Nottinghamshire, in July 2023.
The mosquitoes were tested in pools of 10, with only two pools returning positive results. The remaining 198 samples tested negative.
This marks the first confirmed presence of West Nile virus in mosquitoes in the UK. Follow-up testing at the same site and across the country has not identified any further positive samples.
West Nile virus is a vector-borne disease from the Flaviviridae family, which also includes dengue and yellow fever viruses. The virus is primarily maintained in bird populations and transmitted through bird-biting mosquitoes. In rare cases, infected mosquitoes can pass the virus to humans or horses.
The virus is endemic in many regions across the globe, including parts of Europe, Africa, the Middle East, West and Central Asia, North and South America, and Australia. Its geographic range has been expanding, with recent detections in more northerly and westerly regions of mainland Europe.
To date, there have been no locally acquired cases of West Nile virus in humans or horses in Britain. Since 2000, seven travel-associated human cases have been reported.
