Holidaymakers heading to Spain have been warned to take precautions after the country's first death this year from West Nile virus, with experts fearing the disease could spread to more hotspots.
An 82-year-old man from Dos Hermanas, near Seville, has become Spain's first confirmed fatality from the virus this year after being admitted to hospital with meningoencephalitis caused by the mosquito-borne infection. Spanish health authorities have confirmed at least 19 human cases this season, the vast majority in Andalusia, although infections have also been identified in Alicante and Extremadura.
Peak months ahead
Experts say August and September are likely to be the most dangerous months, as mosquito numbers peak and transmission increases. Rubén Bueno, technical director of pest-control specialist Lokímica, told Spanish newspaper ABC: “August and September are typically critical months for human cases; the vast majority of human cases are concentrated in these two months, as the preceding two months are when we see cases in animals. It is highly likely that more cases will emerge.”
Bueno also warned ABC that the virus may not remain confined to southern Spain. He said: “We certainly cannot rule out the possibility of further affected areas. We know the virus circulates naturally in Extremadura, in parts of the Valencian Community, in Catalonia, and in some areas of Castilla-La Mancha.”
Risk to British travellers
The warning comes as millions of Brits head to Spain during the school holidays, with Valencia and Catalonia among the country's most popular destinations for UK visitors. West Nile virus is spread by infected Culex mosquitoes after they feed on infected birds. It cannot spread directly between people.
According to the World Health Organization (WHO), around 80% of infected people develop no symptoms, while about 20% experience a mild illness including fever, headache and muscle aches. Fewer than 1% develop serious neurological disease such as meningitis or encephalitis, but the risk is much higher in older adults and people with underlying medical conditions.
Latest cases and alert areas
The latest victim, who had existing health conditions, had been receiving treatment at the Virgen de Valme University Hospital in Seville after being diagnosed on July 27, according to Andalusia's Department of Health, as reported by eldiario.es. Regional authorities have also confirmed a new case in Aznalcázar, bringing the total number of infections in Seville province this season to 17. Nineteen municipalities have now been designated alert areas because of virus circulation or infected mosquitoes.
Health officials say alert status triggers intensified mosquito surveillance, monitoring of animals and humans, and public awareness campaigns urging residents and visitors to protect themselves from bites. The current outbreak remains well below the scale seen in 2024, when Spain suffered its worst recorded West Nile virus season, with 158 confirmed human infections and 20 deaths, most of them in Andalusia.
According to ABC, sources at Spain's National Research Council (CSIC) believe widespread infection among birds during the 2024 outbreak helped increase immunity in the bird population, reducing transmission the following year. However, they say the virus remains endemic and the risk persists whenever high temperatures combine with standing water.
European and UK outlook
The World Health Organization has warned that West Nile virus activity has increased across parts of Europe this summer, with locally acquired cases also reported in countries including Italy, Greece, Romania and North Macedonia. The UK Health Security Agency (UKHSA) says there have been no human cases acquired in the UK, although it now regards West Nile virus as an emerging public health risk because climate change is creating more favourable conditions for mosquitoes capable of carrying the virus.
Advice for travellers
Health experts advise travellers to:
- Use insect repellent, particularly at dawn and dusk.
- Wear long sleeves and trousers where practical.
- Sleep in air-conditioned rooms or those fitted with mosquito screens.
- Avoid areas of stagnant water where mosquitoes breed.
- Seek medical advice if they develop a high fever, severe headache, neck stiffness or confusion after returning from an affected area.
