In a 60-page opinion published Wednesday on "the health risks of dengue and other arboviruses" (viruses transmitted in particular by mosquitoes), the former scientific council recalls that the French tropical territories are confronted with it recurrently.

But in recent years, the metropolis has also recorded a growing number of indigenous cases (i.e. not coming from contamination outside the territory) and outbreaks of these viruses.

In question, the mosquitoes Aedes aegypti and Aedes albopictus (commonly called the tiger mosquito).

Since 2010, the number of metropolitan departments colonized by the tiger mosquito has increased 10-fold.

And last summer, the metropolis experienced 65 cases of indigenous dengue, recalls the Covars.

In metropolitan France, no severe form of the disease has been observed to date, unlike in overseas territories where populations are repeatedly exposed.

"The rise in cases is inevitable due to the increase in travel and climate change," Didier Fontenille, entomologist, one of the authors of the report, said at a press briefing.

"Soon the whole hexagon will be affected by the tiger mosquito. As for Aedes aegypti, it is resistant to insecticides, these are two very bad news," he added.

According to Covars, these viral diseases "could become public health problems in metropolitan France".

The upcoming organization of major international sporting events in metropolitan France (including the 2024 Olympic Games), which generate significant migrations of populations from around the world, "increases the risk of dengue, Zika and chikungunya outbreaks," he adds.

"We were already overwhelmed with 65 cases. If next year there are 300, we will not be able to cope, we will have to adapt, "warned Didier Fontenille.

If the France has a system of surveillance, detection, management of these diseases considered "effective", it remains "perfectible", especially in metropolitan France, says the Covars.

In particular, there is a lack of "national coordination" to be informed of the situation in other regions.

"We are not in a catastrophic scenario but we must take the risk seriously by prevention campaigns or a better organization of actors," concluded the president of Covars, Brigitte Autran, during the press briefing.

© 2023 AFP