in Marseille, bait to capture tiger mosquitoes on the Olympic site

While a record number of imported cases of dengue fever has been recorded since the start of the year, the city of Marseille has decided to set up traps for tiger mosquitoes at the Olympic marina site.

Three months before the Olympic Games, how to prevent the tiger mosquito from spoiling the party ? The insect, which is now spreading throughout France, carries diseases such as dengue fever. 45 indigenous cases of this disease, transmitted by the tiger mosquito, were recorded last year in France according to Santé Publique France.

Almost 1 700 cases have also been imported into mainland France since January 1 according to the Directorate General of Health. So to protect athletes and spectators during the Olympics, the city of Marseille has installed traps on the site of the Olympic marina, where the sailing events will take place.

These traps are slipped inside large perforated metal boxes. 15 traps in total, spread over an area of ​​one hectare. “The traps are protected in boxes to avoid any risk of vandalism or accident. They operate on solar panels and inside we have the trap connected to a CO2 bottle. These are traps which will reproduce odors of the human body to attract the mosquito and capture it”details Antoine Cohen, technical manager for Biogents, the company which won the call for tenders from Marseille town hall to protect the Olympic marina.

“Naturally our body gives off many odors: lactic acid, caproic… Some of these acids will be traced by the mosquito to find lactic acid in particular, like an odorous trail that we leave behind us”specifies the expert. So there is no insecticide in these traps, only odors.

Limit the proliferation of tiger mosquitoes

By capturing tiger mosquitoes, the town hall hopes to limit the risk of disease transmission while the Olympics will attract visitors from all over the world. The tiger mosquito could bite a visitor who is already sick, then contaminate several others by carrying chikungunya, zika or even dengue.

“Dengue this year is particularly worrying, there is a significant epidemic in South America and the West Indies”, explains Grégory L’Ambert, medical entomologist, at the EID, the interdepartmental agreement for mosquito control on the Mediterranean coast. According to him, traps are a solution against the proliferation of tiger mosquitoes, but are not enough.

“Even if we have a network of well-installed traps, we cannot guarantee the total absence of risk of local transmission. Mosquitoes are capable of multiplying by 200 every 15 days. If we want to protect ourselves from them, the The first thing to do is to limit their proliferation.”

Grégory L’Ambert, medical entomologist

at franceinfo

For this, everyone must mobilize to avoid stagnant water in gardens, on balconies or in the street. A few millimeters are enough for tiger mosquitoes to develop there, and larvae are already present at this time.