Innovative Mosquito Control: French Towns Deploy Sterilized Tiger Mosquitoes to Combat Invasive Species

A French commune in the Rhône department is releasing 200,000 sterile tiger mosquitoes as part of an innovative public health initiative aimed at reducing the population of disease-carrying insects.

The initiative, reported by Orange Actualités, involves the deliberate release of sterile male tiger mosquitoes in a commune east of Lyon to combat the spread of Aedes albopictus, commonly known as the tiger mosquito. This species is capable of transmitting dengue, Zika, and chikungunya viruses and has become established in 78 of France’s 96 mainland departments since its first detection in 2004.

The method employed is the Sterile Insect Technique (SIT), a scientifically validated approach in which male mosquitoes are sterilized—typically through irradiation—and released into the wild to mate with females. Because female tiger mosquitoes mate only once in their lifetime, encounters with sterile males result in non-viable eggs, thereby suppressing reproduction and reducing future populations.

This approach has been previously tested in other regions of France. In Nouvelle-Aquitaine, authorities in Brive-La-Gaillarde released an initial batch of 40,000 sterile males in May 2025, with plans to release up to 10 million over the season at a cost of €52,000. Residents reported that the previous summer had been particularly severe due to mosquito nuisance and health concerns.

In Montpellier, the startup Terratis has implemented a similar program in the Malbosc neighborhood, releasing 200,000 sterile male tiger mosquitoes weekly from August to October 2025 across 26 targeted locations. According to Clélia Oliva, CEO of Terratis, this effort reduced tiger mosquito populations by 50% to 60% in the first year, with potential for up to 80% reduction in subsequent years. The company uses automation in its breeding process and focuses on interrupting the insect’s life cycle by targeting eggs laid in the fall that survive winter to hatch in spring.

Terratis was recognized in October 2025 with the i-Lab “Better Living” Grand Prize from Bpifrance for its innovation in public health. The startup emphasizes that its method uses no insecticides, relying solely on the biological principle of sterile male releases to limit proliferation.

Other French startups have also explored variations of SIT. A Montpellier-based company highlighted in The Local in May 2025 suggested that irradiation with gamma or X-rays could cut mosquito reproduction by up to 90% within two years. Research from CIRAD has investigated a “boosted” version of SIT in which sterile males carry minute quantities of a biocide to further disrupt breeding sites, based on field trials in Réunion and Spain targeting Aedes aegypti.

While the tiger mosquito does not currently transmit endemic diseases in France, public health officials remain vigilant due to the risk of imported cases triggering local transmission. The sterile insect technique offers a chemical-free alternative to traditional pest control, aligning with broader efforts to reduce environmental impact while managing vector-borne disease threats.