Doctors Warn of Rising Mosquito-Borne Disease Risk in Southern Spain This Summer

A Growing Health Risk as Summers Get Hotter

Spanish health authorities are warning of increasing mosquito-borne illness risks in southern Spain this summer, particularly across Andalusia and Mediterranean coastal areas. While malaria was eradicated from Spain decades ago, other viral diseases transmitted by mosquitoes are becoming more prevalent — driven by rising temperatures, milder winters, and the spread of invasive mosquito species into European regions where they were not previously established.

The Three Main Threats

West Nile Virus

West Nile Virus is already established in Spain. Transmitted primarily by Culex mosquitoes, it has been detected in both human and animal populations, especially in southern provinces. Most infections cause no symptoms and pass unnoticed — but severe cases, particularly in elderly or immunocompromised individuals, can develop into meningitis or encephalitis requiring hospitalisation. This is the most immediate concern for residents of southern Spain.

Dengue Fever

Most cases of Dengue in Spain remain travel-related — brought back by people returning from tropical regions — but local transmission has occurred when infected travellers were bitten by Aedes mosquitoes already present in Spain. Symptoms include sudden high fever, severe headache, pain behind the eyes, and intense joint and muscle pain. Most people recover within one to two weeks, but the illness can be debilitating.

Chikungunya

Chikungunya produces fever and fatigue alongside a hallmark symptom: intense joint pain that can persist for weeks or even months after the acute infection has passed. It is transmitted by the same Aedes mosquitoes implicated in Dengue, and the expanding range of these species across southern Europe raises the risk of local cases.

Why the Risk Is Growing

Three factors are converging to increase the threat level:

• Rising temperatures and milder winters in southern Spain are extending the mosquito breeding season, allowing populations to build earlier and persist later into the year
• Invasive mosquito species — particularly the tiger mosquito (Aedes albopictus) — have established themselves across significant parts of Spain and other European countries, bringing disease transmission potential that native species did not carry
• Climate change is accelerating mosquito development and can shorten the viral incubation period within the insects themselves — meaning infected mosquitoes become capable of transmitting disease faster

How to Protect Yourself

Health authorities recommend the following preventive measures:

• Eliminate standing water around your home — flowerpot trays, buckets, gutters and anything that holds still water provides breeding grounds. Even small amounts matter for tiger mosquitoes.
• Use insect repellents containing DEET or picaridin, particularly during dawn and dusk hours when mosquitoes are most active
• Wear long sleeves and trousers at dawn and dusk, especially in rural or semi-rural areas near water
• Install window and door screens if you do not already have them — standard in northern Europe but less universal in Spanish homes
• Use mosquito nets at night if you sleep with windows open

For expats and residents in Andalusia, the Costa del Sol, the Costa Blanca and other southern coastal areas, these precautions are worth building into summer routines — especially for households with elderly residents or anyone with underlying health conditions.

This article is based on reporting from Euro Weekly News, published April 29, 2026.