Scientists have issued an urgent warning about a potential health threat to Europe after research found climate change could leave the continent vulnerable to a deadly virus.
Researchers have revealed the West Nile virus, or WNV, could become more prevalent in Europe as temperatures rise.
WNV is a single-strain virus that causes West Nile fever and is typically transmitted to humans via mosquitoes.
It was first identified in Uganda in 1937, but since then has also been detected across Africa as well as in North America, Europe, the Middle East and West Asia.
Most people infected with West Nile fever are asymptomatic, while around 20 to 25 percent develop a fever and headaches.
Around just one percent of patients will experience severe neurological complications that can lead to death.
To date, locally acquired WNV infection has not been reported in the UK, although there have been occasional cases of travel-associated infection.
Therefore, the main risk of WNV for UK residents has been for those travelling abroad.
The same is true for most parts of Europe, however, in July last year French authorities confirmed the existence of the first non-imported human case of infection by this virus in Bordeaux.
Scientists have hypothesised that this could be linked to climate change and rising temperatures, but a study, published in 2023 confirmed this is likely the case.
The research, published in the journal Nature Communications, concluded: “Our results show up to five-fold increase in West Nile virus (WNV) risk for 2040-60 in Europe, depending on geographical region and climate scenario, compared to 2000-20.
“The proportion of disease-reported European land areas could increase from 15 percent to 23 to 30 percent, putting 161 to 244 million people at risk.”
And separate to this, researchers at the Space Epidemiology Laboratory at the Université Libre de Bruxelles in Belgium, were able to demonstrate the contribution of climate change to the spread of the virus in Europe.
To do so they trained an “ecological niche” model that establishes the mathematical relationships between local environmental conditions and the risk of local circulation of the virus.
As reported by RTBF in Belgium, Simon Dellicour – supervisor of the study and lab director – said: “Once we had trained this model, in the present time, on real data, we went back in time, both according to the observed scenario – i.e. the real environmental conditions that evolved in the last century -, and also according to a scenario provided to us by climatologists, where climate change has been removed and CO2 emission conditions have remained at the level of the beginning of the last century.
“This makes it possible to compare how the risk of local circulation of the West Nile virus in Europe evolves in a scenario where there is no climate change and in the scenario where there has been climate change, i.e. the real scenario”.
He added: “This is clearly a new virus circulating in certain European countries. So it’s a new public health problem.
“It’s a virus whose progress we need to analyse, because it’s a new public health issue that we’re going to have to live with in Europe, whereas this disease wasn’t present in our country just a few years ago”.
According to the NHS, most patients do not experience symptoms of West Nile fever.
But signs of a severe infection can include flu-like symptoms and also:
- Muscle weakness
- Confusion
- Fits (seizures).
The health body advises seeking medical advice if you notice symptoms while travelling or upon returning home. It is not contagious.
