Stripes

Tiger mosquitoes are in Luxembourg. Not passing through. Not occasional visitors. Regularly present, at two or three known locations, with more expected as the climate continues to shift in their favour.[1]

The Asian tiger mosquito, Aedes albopictus, is small, black, with white stripes on its legs and a single white stripe down its back. It bites during the day, unlike most native mosquitoes, which prefer dusk. It does not need standing water to breed in the usual sense; it needs only a container, a puddle, a flower pot saucer with a few millimetres of rain. Its eggs can survive dry conditions for months, hatching when water returns. Emptying a rain barrel is not enough. You have to scrub it.[2]

It carries dengue fever, chikungunya, Zika, and West Nile virus. None of these diseases are currently being transmitted locally in Luxembourg, but the mosquito is here, and the question of transmission is no longer hypothetical. Last year, France recorded 450 locally transmitted cases of chikungunya and 16 of dengue in the Provence-Alpes-Cote d'Azur region alone, between June and November, across 35 distinct transmission episodes. No one had travelled abroad. The mosquitoes were local. The infections were local. Sixty percent of all locally acquired cases in mainland France came from a single region where 97% of the population now lives alongside the insect.[3]

Luxembourg's Health Directorate is running a network of traps at the country's entry points: Berchem, the Aire de Capellen service area, Findel airport, Bettembourg, Kockelscheuer, and the Bouillon Park and Ride. Some traps mimic human scent to attract adults; others collect eggs from females looking for water. Inspectors check around 50 collection tubes every two weeks. Genetic testing at the Luxembourg Institute of Science and Technology (LIST) can distinguish between four invasive mosquito species and determine which viral diseases each might carry.[4]

By the end of May, no tiger mosquito eggs had been found in the traps. Isabelle Karreck of the sanitary inspection service noted that it may simply be too early in the season. The insects spend the winter as eggs, hatching when temperatures rise and days lengthen. The monitoring programme is designed as an early warning system, not a confirmation of absence.[5]

Authorities have already begun applying targeted biocides against mosquito larvae in urban infrastructure, drains, and sewers. Rural areas are not treated. Residents are advised to eliminate standing water around their homes and to scrub containers rather than simply emptying them, because the eggs cling to surfaces and survive desiccation.[6]

France activated its stepped-up tiger mosquito surveillance system on 1 May this year, in direct response to the 2025 figures. Sant publique France and the regional health agencies are now requiring mandatory reporting of any confirmed case of dengue, chikungunya, or Zika, whether imported or locally transmitted. Each case triggers an investigation to identify potential transmission sites. Interdepartmental mosquito control teams are deployed around confirmed cases.[7]

Luxembourg has 30 native mosquito species. Four of them are invasive. The country is small, densely populated, and heavily connected by road, rail, and air to regions where transmission is already happening. The traps at Capellen and Findel are not decorative. They are where the border between absence and presence gets measured, two weeks at a time.

Members of the public can report suspected tiger mosquito sightings through the Mosquito Alert app, preferably with photographs, to help authorities track the spread and respond if further control measures become necessary.[8]