The drone, the tool of the future to combat its spread

French researchers said on Tuesday that drones could, within a few years, integrate into the arsenal of the fight against the tiger mosquito, an invasive species that appeared on mainland France about fifteen years ago, revealing the results of an experiment conducted in Montpellier.

The tiger mosquito, Aedes albopictus, now discovered in 65 French provinces, grows 80% in individuals, mainly in stagnant water in parks. It turns out to be more harmful because it bites constantly throughout the day and can transmit viral diseases such as dengue, chikungunya or Zika if it has bitten a patient before.

Therefore the first preventive measure against this insect, whose spread favors high temperatures, is to systematically empty and invert containers that may contain water, such as a simple ashtray.

But additional methods have emerged in recent years, including the so-called “sterile insect technique” (TIS), which consists of raising male mosquitoes in laboratories, sterilizing them, and then releasing them into the field, where wild females are sterilized. which will not have offspring.

Experiences at Herault

“Mosquito control” specialists from EID-Méditerranée, a public company based in Montpellier, had the idea of ​​upgrading the equipment with a drone for better deployment.

With the support of CIRAD, an agricultural research organization, in July and August they released approximately 40,000 sterile males imported from Italy into a residential area of ​​Prades-le-Lez, about ten kilometers north of Montpellier, with the consent of the residents and the municipality.

The use of drones made it possible to release more male mosquitoes at a height of 40 or 50 meters from the ground, and at a faster speed than usual methods. In addition, these males are generally well distributed in the region, explained Charles Jenin, a medical entomologist at EID Mediterranean, and judged these results as “extremely encouraging”.

However, at the end of this experiment, the researchers did not observe a significant decrease in female fertility. So there was no decrease in the tiger mosquito population in Prades-le-Lies either.

“For this to work well, it would be necessary to release 10 times more sterile males than wild females”, which would require in particular the “industrial” production of the males, the general manager of the feast emphasized. The Mediterranean, Bruno Toure. More studies will be necessary, Bruno Toure said, and the method that combines sterile insect technology with the use of drones is not expected to be generalized for at least five years.