A DEADLY bug often mistaken for flu has claimed dozens of lives in Europe this year as it edges closer to the UK.
West Nile virus has infected over 989 people across 13 countries this summer, far higher than the for what is normal for this time of year.
Wst Nile is transmitted through bird-biting mosquitoes[/caption]
At least 63 victims have died, with popular British tourist hotspot Italy the worst hit, followed by Greece, Serbia and France.
And the threat feels closer than ever after the debilitating virus was detected in a mosquito on British soil for the first time.
For most people, the bug won’t cause symptoms at all. But some may be struck with flu-like aches and pains, headaches and fever.
For around one in 150,the virus can be severe – triggering life-threatening illness, like paralysis or even death.
Scientists identified fragments of the infection in the genetic material of UK mosquitoes for first-the time in 2023 – but only announced the discovery this summer.
The virus is usually found in birds and circulates through bird-biting mosquitoes. It can be transmitted to horses as well as humans.
In the last 25 years, only seven cases have been brought into the UK by travellers – and none have caught it locally.
The warming climate has meant different species of disease-carrying mosquitoes, are able to survive on the British Isles. This has sparked fears killers like malaria could one day take hold.
Meanwhile, eggs laid by mosquitos that carry dengue and chikungunya near Heathrow and a motorway service station on the M20 for the first time, according to a paper published in PLOS Global Public Health last month.
West Nile is already commonly found across Africa, Asia and the Americas, and has expanded in recent years to more northerly and western parts of Europe.
Since June 2025 and up to September, 13 European countries have reported 989 cases of West Nile virus leading to 63 deaths, according to infection data from the European Centre for Disease Control (ECDC).
Most infections were in Italy (714), followed by Greece (91), Serbia (60), France (42) and Romania (36).
Followed by Spain (23), Hungary (11), Croatia (4), Albania (3), North Macedonia (2), Bulgaria (1), Kosovo (1) and Türkiye (1).
Infection numbers so far in 2025 are already well above the 10-year average of 687 cases for the same period.
But they remain below the surges seen in 2018, 2022 and 2024, when more than 1,000 infections had been recorded by this point.
ECDC health chiefs warn this year’s tally may rise further as reporting is often delayed.
Cases of West Nile virus have been reported for the first time this year in the Italian provinces of Latina and Frosinone, as well as in Sicily, Calabria, Tuscany and Liguria.
In France, the first-ever infections were detected in Seine-Saint-Denis, Puy-de-Dôme and Vaucluse, while Romania recorded its first case in Sălaj County.
The 7 key symptoms to know
Prof Tom Solomon, from the NIHR Health Protection Research Unit on Emerging Infections and the Pandemic Institute in Liverpool said West Nile virus mostly causes a flu-like illness in people.
But it can also “infect people with no symptoms at all”.
People infected with the bug may experience:
Symptoms typically take two to 14 days to appear after infection and should go away within three to six days, according to the UK Health Security Agency.
Prof Solomon added: “In a small proportion of patients, the virus can cause neurological disease, which may lead to paralysis or even death.
“Unfortunately, there is no specific treatment.”
Other mosquito-borne diseases and how to protect yourself
Vector-borne diseases – illnesses transmitted to humans by organisms such as mosquitoes and ticks – are a growing threat to the UK and Europe.
They account for more than 17 per cent of all infectious diseases globally, causing over 700,000 deaths annually, according to UKHSA.
They include:
- Malaria
- Dengue
- Yellow fever
- Zika
- Chikungunya
The Fit for Travel website says if you are travelling to an area affected by diseases such as malaria, dengue fever and yellow fever, spread by mosquitoes, you should take action to protect yourself.
Some mosquitoes are more active in the daytime while others at night – so it is important to protect yourself at all times.
It says: “If you develop a high temperature (fever) either during or after travelling to an affected area, you should seek medical advice as soon as possible and give details of your recent travel history.”
To protect yourself:
Use a good quality insect repellent
The higher the strength, the longer the repellent should prevent mosquitoes landing on you.
An effective repellent contains at least one of; DEET (50% concentration for areas where there is malaria), Icaradin/Picardin (at least 20% concentration, Eucalyptus citriodora oil, hydrated, cyclized (at least 30% concentration), IR3535 (but not for malaria areas).
Apply:
- On all areas of skin not covered by clothing
- After sun screen
- Regularly, particularly if you notice mosquitoes around you
- After swimming, washing or excessive sweating
- On the face, by spraying the repellent on the hands first
Loose clothing
Mosquitoes can bite through tight clothing, so loose-fitting clothing is ideal.
Consider a high neckline, long sleeves, long trousers and socks.
Remember to apply insect repellent on areas not covered by clothing.
Mosquito nets
Mosquito nets can protect you at night when sleeping and are even better if treated with insecticide.
Check for any holes in the net before using it. If a hole is apparent, then this should be mended.
You should tuck the net under your mattress or ground sheet during the night, and either collapse it down, or keep it tucked up during the day to stop insects flying under and into the net.
