In late April, Santé publique France raised concerns about the increasing number of imported cases of dengue in France. Between January 1st and April 19th, 1,679 cases of this disease were reported, with most coming from the Caribbean. Imported cases pose a risk of local transmission, as the mosquito capable of transmitting dengue, Aedes albopictus or the tiger mosquito, is now established in 78 out of 96 departments, according to the Ministry of Health. An infected person can thus infect others through mosquito bites.

As the female mosquitoes are the only ones responsible for biting and have a limited range of about 150 meters, authorities are promoting prevention methods as the Paris Olympics approach. This includes encouraging the use of protective clothing and skin repellents.

What is the ideal mosquito repellent to prevent bites? It should be easy to apply, non-toxic to humans and the environment, effectively repel mosquitoes for as long as possible, have no unpleasant odor, and leave no residue on clothing. There are various options available in the market, ranging from products for temperate or tropical areas, for families, based on synthetic or natural molecules.

In their July-August 2024 issue, 60 Millions de consommateurs compared 15 mosquito repellents (such as Autan, Cinq sur cinq, Insect écran, Moustifluid, Puressentiel), many of which were sprays. While sprays are more common on shelves, the High Council of Public Health prefers lotions or creams for easier application and reduced inhalation risk.

Their tests confirmed the effectiveness of products containing IR3535 and DEET, synthetic molecules with the longest protection duration. However, the active ingredient alone is not everything, as there were differences in protection duration between products with 20% concentrated IR3535. Clarity on protection duration in product labeling is crucial, as misleading presentations can confuse consumers.

Products with natural active ingredients showed more variable protection durations, with some falling short of their claims in the test. Users should be cautious about eye irritation from repellents and potential damage to certain materials like plastics and synthetic fabrics. Different concentrations are recommended based on age and pregnancy status, with higher concentrations allowed in tropical areas due to increased risk and environmental factors.

While tropical repellents are not necessary for metropolitan areas, they may be more effective in laboratory conditions than temperate zone repellents. It is essential to follow product guidelines regarding age restrictions, application quantity, and frequency. Concentrated repellents are not always the best choice, as other protective measures like clothing, nets, fans, and air conditioning can also be effective.

In conclusion, choosing the right mosquito repellent involves considering factors like active ingredients, protection duration, potential risks, and product guidelines. Being informed and following recommendations can help individuals protect themselves from mosquito-borne diseases effectively.