Evaluation of West Nile Virus Transmission Risk in the UK

 

West Nile disease has been sporadically present in certain parts of mainland Europe for about 60 years, but recently it has spread geographically and has increased dramatically in incidence; the number of human cases in 2018 (over two thousand) significantly exceeded previous years, possibly in response to unusually warm weather. Such conditions are expected to occur more frequently, and eventually become the norm, under climate change scenarios.

The primary vector of West Nile virus in mainland Europe is the mosquito Culex modestus. After several decades, this species was rediscovered in southern England in 2010 and it has now been detected over a large area of southeast England (Kent and Essex). It is not known if the vector is actively spreading or has been present in England for some time and is being detected more readily now because of active surveillance.

There have been no human or equine cases of West Nile in the UK but this is not grounds for complacency; there had previously been no cases in the USA but, after its appearance in 1999, West Nile virus is now endemic, found across the continent and is responsible for hundreds to thousands of cases each year, and has caused over two thousand human deaths in 20 years.

West Nile virus has, to date, not been detected in UK Culex modestus mosquitoes, consistent with the virus not being present in the UK at present, but preliminary research has shown that this species, and other UK endemic mosquitoes, are competent vectors of the virus. While transmission is possible, it is not known if the UK climate is suitable; where in the UK is most suitable; and how the risk to the UK may change in future as our climate warms.

To assess the risk of, and increase preparedness for, West Nile transmission in the UK, this project will address the following objectives
Work plan
1. Field studies of the distribution of Culex modestus in southeast England
2. Phylogeographic study of Culex modestus in the UK, to provide evidence of whether the population is stable, or spreading to new areas
3. Development and deployment of FTA cards as a screening tool for WNV
4. Screening of Culex modestus and birds/horses for WNV
5. Studies of the vector competence of Culex modestus to transmit West Nile virus under a range of UK temperatures, using mosquitoes derived from the field and/or from a laboratory colony
If Culex modestus is successfully colonised, we will also take advantage of the opportunity and assess it competence for other invasive viruses, such as Usutu.

For any enquiries please contact: Prof M Baylis on matthew.baylis@liverpool.ac.uk

To apply please send your CV and covering letter to: pgrapps@liverpool.ac.uk

More here: University of Liverpool 

 

Posted on: 20/05/2020