Professor Malvy, infectious disease specialist at Bordeaux University Hospital, is warning. In May, the tiger mosquito is able to transmit it to another person by biting a person infected with dengue fever. “Hence the fact that we must anticipate with very simple citizen gestures,” he says. We followed a prevention operation in Talence, in Gironde.
Prevention operations have multiplied in recent years almost everywhere in France, including in urban areas. Agents from the city of Talence and the Bordeaux Métropole mosquito control center travel to individuals’ homes to intervene and warn. The operation called “Zero mosquitoes” was launched in 2023. It consists of giving some advice to residents to avoid the proliferation of the tiger mosquito by preventing it from laying eggs. In fact, more than 80% of these lodgings are located in private areas.
To do this, any water retention likely to accommodate the larvae must be eliminated. That day, the agents put a bacillus in the water collections which will attack them biologically. “This bacteria will release toxins which will attach to the cells of the intestinal wall and cause it to burst,” explains Christophe Courtin from the Mosquito Control Center. To avoid spoiling your summer evenings, all you need is a few simple steps. “We empty the saucers, we look in the gutters, and we wash them well”, says Hélène Moreau, resident of Talence. “The man from the town told us that there could also be some under the terraces, so that’s another problem, I want to say.”
In Talence, city officials are trying to identify places conducive to the reproduction of the tiger mosquito.
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© FTV
In Talence, agents delivered a questionnaire to residents to determine their current feelings about the quantity of mosquitoes. “The results will be compared to those obtained during their subsequent visits, which will take place every month”explains the City of Talence.
Agents will thus know within a few months whether the proliferation has been contained.
The tiger mosquito was spotted for the first time in New Aquitaine in 2012. It was in Lot-et-Garonne. It then developed towards the Atlantic coast and large urban centers. As a result, today, it is present everywhere in our region except in Creuse. He sometimes carries the dengue virus.
The tiger mosquito is present everywhere in New Aquitaine, except in Creuse.
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© FTV
For Professor Malvy, infectious disease specialist at Bordeaux University Hospital, there is no doubt that climate change has effects on the spread of certain viruses through the tiger mosquito. “Climate change impacts dengue disease through the virus and the mosquito”he analyzes. “Because mosquitoes need water and heat. And the more there are unexpected environmental phenomena or with distortions like what we are targeting with strong alternations, drought, then intense rainfall… All this makes life easier for the mosquitoes.
However, the professor refuses to talk about mosquito control and prefers to talk about “vector risk prevention”. “Dengue fever, which concerns us more particularly, is a virus which is transmitted practically from man to man by the tiger mosquito. he explains.
This is a risk that must be considered for France in mainland France.
Professor Denis Malvy,Bordeaux University Hospital Infectious Disease Specialist
For what ? “Because we have an extremely significant increase with intercontinental travel in a globalized world of people who come from endemic or epidemic areas such as, for example, the Lesser Antilles, the Caribbean or Guyana and who arrive in France in France where there is a mosquito capable of transmitting this virus.
To support his remarks, Professor Denis Malvy relies on a reality. “At Bordeaux University Hospital, for example, we have two to three patients suffering from viremic dengue, that is to say symptomatic, per week. he announces. “And this has been happening for months and months.”
With the month of May, we enter the period when the tiger mosquito present in Aquitaine becomes active.
Professor Denis Malvy,infectious disease specialist Bordeaux University Hospital
“That is to say, when it bites a viremic person, it becomes capable of transmitting it to another person. It is therefore a risk of transmission that, chronologically, we encounter.
“And this year, with the number of travelers returning with viremia, there is nothing to stop us, the risk is inevitable, from having indigenous cases in France and Aquitaine. But we are anticipating it.”
In 2023, the tiger mosquito was present in 71 departments in France. It can also transmit to humans viruses like chikungunya or Zika.
