Dengue fever is becoming more prevalent in parts of Europe due to climate change, researchers have warned after a woman from the UK was infected while on holiday in the south of France.
A 44-year-old woman, who has not been identified, was infected with the tropical disease during a trip to Nice, southern France, in September 2022.
She had experienced fever, headache, muscle pain and a rash for three days but did not require further medical treatment.
Her diagnosis was made by the UK’s Rare Imported Pathogens Laboratory (RIPL) after the woman visited an emergency department after returning home to UK and doctors sent an urgent sample for analysis.
Surveillance and reporting mechanisms are important in ensuring we have an accurate understanding of dengue spread— Dr Owain Donnelly
Dr Owain Donnelly from the Hospital for Tropical Diseases, London said: “This individual was part of an outbreak of over 30 locally transmitted cases in the south of France in 2022, which highlights the rapidly changing epidemiology of dengue.
“With climate change, particularly hotter temperatures and more rainfall, and increasing global trade and tourism, we may see more parts of Europe with the right combination of factors for dengue outbreaks.
“Surveillance and reporting mechanisms are important in ensuring we have an accurate understanding of dengue spread.”
The woman had returned from the south of France the day before symptoms started and had not travelled to any other countries.
Family she stayed with in France also experienced similar symptoms.
Dengue fever is spread by the bite of mosquitoes infected with the dengue virus, typically in tropical regions in Asia, South America, and Asia.
However climate change has led to the increased presence of the Asian tiger mosquito, a carrier of the disease, throughout southern Europe.
Most UK infections of the virus are diagnosed in travellers who have recently visited these regions.
It has flu-like symptoms but an estimated 75% of cases are asymptomatic and can go undetected.
In severe cases, 1 to 5% of patients develop potentially fatal severe dengue or dengue hemorrhagic fever.
The case was presented by Dr Donnelly to the European Congress of Clinical Microbiology & Infectious Diseases in Copenhagen.
Between June and September 2022, the Agence Regionale de Santé (ARS) in France reported three separate outbreaks of dengue virus transmission contracted on national territory without patients having travelled abroad.
