THE FIRST case of "indigenous" dengue fever has been recorded in the Var department of southeast France, the regional health authority announced.
The patient contracted the illness despite not having travelled to a part of the world where the virus is known to be circulating in the past 15 days, the agency said.
“At the moment, this is a unique and geographically isolated case and there is no immediate concern about the patient’s condition,” it added in a statement.
Dengue fever is spread by the Asian tiger mosquito, which first arrived in France in the Alpes-Maritime in 2004 and has now spread to 18 metropolitan departments, mainly in the south of the country.
Medical authorities in the Var are working to stop the spread of the disease by using powerful insecticides around the patient's home, along with other mosquito controls.
Earlier this month, authorities in the Riviera revealed cases of dengue and chikungunya in the region were on the rise - but all previously reported cases were contracted in disease hotspots such as the Caribbean or Brazil.
In France, two cases of indigenous dengue fever were reported in Nice in 2010. In the same year, two indigenous cases of chikungunya were recorded in Frejus.
But the disease is widespread in a number of French territories. A serious outbreak in the French Antilles in 2010 resulted in the mobilisation of the army.
Symptoms of the disease include fever, headache, muscle and joint pain, and a skin rash similar to measles. In rare cases it can develop into the life-threatening dengue hemorrhagic fever or dengue shock syndrome.