Nice Premium: How do you explain the fact that there have been 4 cases of non-imported tropical diseases in the PACA region?
Pascal Delaunay: The Asian tiger mosquito, Aedes albopictus, has been present in the Alpes-Maritimes since 2004. It has spread since then to the Var, the Bouches-du-Rhône, and Corsica. This mosquito has always been monitored by the Ministry of Health and entomological experts because it is a vector of tropical diseases in tropical regions. There was always this epidemic risk of chikungunya or dengue as long as this mosquito was present.
NP: What are the risks in France of contracting chikungunya or dengue?
PD: They are minimal. For now, there have been two cases each of dengue and chikungunya. It’s really just bad luck for these four people. They are doing well. The risk is minimal. Moreover, there is a surveillance system implemented by the Ministry of Health to closely monitor everyone returning from tropical areas with chikungunya and dengue, in order to quickly block an epidemic. This system, in place since 2006, has enabled the rapid detection of the four autochthonous cases of dengue or chikungunya.
NP: Is chikungunya or dengue a parasite or a virus?
PD: They are viruses transmitted by arthropods; that is, by insects, ticks, or others. This refers to the group of arboviruses, which are viruses transmitted by arthropods. Chikungunya and dengue are arboviruses, meaning they can multiply in the Asian tiger mosquito and then, during a subsequent mosquito bite, this virus can be transmitted to you.
NP: What is the difference between a parasite and a virus?
PD: A virus is an extremely simple structure with a protective membrane or capsule containing only genetic code. It is a structure highly dependent on living cells, as it can generally only live within cells. A parasite, on the other hand, is a completely different living structure with a membrane containing a nucleus and many small organelles, making it a fully autonomous microorganism that is not at all structured the same way as a virus.
NP: Why does the Asian tiger mosquito spread these diseases and not others?
PD: In France, only the Asian tiger mosquito can multiply the chikungunya or dengue virus. It is the only one with receptors in its stomach that allow the dengue or chikungunya virus to identify and infect it. Once the virus finds the right mosquito, it can multiply. When the chikungunya or dengue virus is in other mosquitoes, it does not recognize the receptors and cannot multiply.
NP: What precautions do you advise the public to take to avoid contracting these diseases?
PD: There are two main precautions. The first is to minimize the number of mosquitoes and, especially, larvae around you. This means removing all saucers and water containers where larvae can multiply. These measures have a significant impact on reducing the nuisance and the number of mosquitoes that might bite you. Then there are personal protections where you should wear long-sleeved clothing. You can also apply repellents on your skin or use an electric insecticide diffuser in rooms.
NP: Do you recommend taking a preventive treatment?
PD: Absolutely not. There is no need to take treatment. In any case, there is no specific treatment for chikungunya or dengue.
NP: What should a person do if they contract one of these diseases?
PD: The person should rest and take medication like Paracetamol. If nothing worsens, that’s all that needs to be done.
NP: If these diseases worsen, what should be done instead of taking Paracetamol?
PD: In any case, to know if you have contracted chikungunya or dengue, you would have visited your doctor because of headaches and fever. The doctor will suspect chikungunya or dengue and will order tests to confirm if you truly have chikungunya or dengue. If the illness worsens, you should return to your doctor or possibly be hospitalized.
NP: How long does it take to know if one has these diseases?
PD: There are different techniques, but it can be determined within a week.
NP: How long will the risk period last in France?
PD: As long as the Asian tiger mosquito is still active. This is from mid-May until the end of November approximately.
