Andorra's trails call for a tick check. Its valley towns have a new mosquito.
- No CDC travel notice for mosquito-borne disease
No mosquito-borne disease has been reported in Andorra, and mosquitoes tend to be sparse in the mountains. On a summer hiking trip the routine that matters is a tick check, and in Andorra la Vella and the towns around it a daytime repellent now helps too.
Are there mosquitoes in Andorra? A few. They tend to be sparse on the mountain trails, and no mosquito-borne disease has been reported in the country. The bites to plan for in summer are ticks in the meadows, horse flies around grazing livestock and, since 2025, the Asian tiger mosquito in the valley towns.
Ticks on the trails
The castor bean tick, Ixodes ricinus, is the common species on both sides of the Pyrenees. The figures here come from studies elsewhere in the Pyrenees, across the border in France and Spain. At Pic de Bazès in France's Hautes-Pyrénées, ticks collected from 2009 to 2015 carried the Lyme disease bacterium (8.4% of 696 tested), Anaplasma (6.1%) and Rickettsia (17.6%), a 2019 study in Parasite found. In the Spanish central Pyrenees, ticks taken from lizards at about 5,600 feet (1,700 m) in 2024 carried Rickettsia in 15.4% of pooled samples and no Lyme bacteria, a 2026 study in Parasitology Research reported.
CDC's Andorra page advises a repellent with 20% or more DEET "for protection against ticks and mosquitoes" and checking "your entire body for ticks after outdoor activity." Tuck long trousers into socks, consider permethrin-treated clothing for multi-day hikes and remove any tick promptly. Long, light-colored sleeves tend to help against horse flies. Ticks tend to stay active from spring into autumn, so a May or October hike needs the same check.
A new mosquito in the valley towns
A 2025 study by Andorra Recerca + Innovació found the Asian tiger mosquito in Andorra for the first time, local press reported. Most finds were in Sant Julià de Lòria, Andorra la Vella and Escaldes-Engordany, along the Gran Valira. According to the same reports, October samples included cold-resistant eggs, a sign it may survive the winter, and the government has responded with a surveillance plan, treatments at public hotspots and an awareness campaign. It bites by day, so repellent on a town terrace handles it. CDC's page lists dengue, which this mosquito can spread, but no local case has been reported in Andorra, and Spain had no local dengue in 2025 or 2026.
Where you're going
Andorra la Vella & Escaldes-Engordany
The capital and its spa-and-shopping twin town, where the tiger mosquito was reported in 2025. Daytime bites on garden terraces and café patios are now possible, so carry a small repellent.
Grandvalira: Soldeu, El Tarter, Canillo & Pas de la Casa
Lift-served hiking and biking in the east. Ticks in the meadows and horse flies near grazing livestock are the likely bites, so tuck trousers into socks and check for ticks after each outing.
Vallnord & the Comapedrosa trails
The northwest resorts and the route to Andorra's highest peak. Mosquitoes tend to be few, so the routine is a full tick check after meadow and forest walks.
Combining Andorra with Barcelona or southern France? Our Spain briefing covers the daytime tiger mosquito from Barcelona to Mallorca, and our France briefing covers Provence and the Riviera.
The Andorra kit
- Permethrin 0.5% for hiking clothes: treat trousers, socks and boots at home 48 hours before you fly. Treated fabric repels and kills ticks on contact through several washes. Clothing only, never skin.
- Picaridin 20% travel sprays for daytime in the valley towns. For skin on the trails, CDC suggests DEET 20% or more.
- Fine-tipped tweezers for removing ticks.
One more rule outlasts the trip. Any fever during or after your trip, or a spreading rash in the weeks after a tick bite, means a doctor visit, and you tell the doctor you were hiking in Andorra.
Traveler questions
Are there mosquitoes in Andorra?
A few. Native mosquitoes turn up near still water, and they tend to be sparse on the mountain trails. Since 2025 the Asian tiger mosquito has been reported in the valley towns of Sant Julià de Lòria, Andorra la Vella and Escaldes-Engordany, where it bites by day. No mosquito-borne disease has been reported in Andorra.
Do I need to worry about ticks when hiking in Andorra?
Plan for them. The castor bean tick is common on both sides of the Pyrenees, and at Pic de Bazès in France's Hautes-Pyrénées, 8.4% of ticks tested carried the Lyme disease bacterium. CDC advises a repellent with 20% or more DEET and a check of your entire body after outdoor activity. Remove any tick promptly with fine-tipped tweezers, and see a doctor for a spreading rash or a fever in the weeks after a bite.
Do I need vaccines or malaria pills for Andorra?
CDC's Andorra page has no malaria section and lists no malaria medicine, and the yellow fever vaccine is neither recommended nor required. The page has no tick-borne encephalitis section, and there is no CDC travel notice for mosquito-borne disease.
Sources
Health authorities, surveillance reports and news coverage of official bulletins used for this briefing, last checked October 2026. Traveler reports are linked where they appear. This page summarizes public-health guidance and is not medical advice.
- CDC destination page for travelers
- European Centre for Disease Prevention and Control
- European Centre for Disease Prevention and Control
- Health authority (santepubliquefrance.fr)
- European Centre for Disease Prevention and Control
- European Centre for Disease Prevention and Control
- European Centre for Disease Prevention and Control
- European Centre for Disease Prevention and Control
- Peer-reviewed study (PubMed Central)
- Peer-reviewed study (PubMed Central)
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