Chikungunya in Italy, dengue on the Côte d'Azur … And one day in Scandinavia? Europe must prepare for epidemics hitherto reserved for tropical regions, warns researchers, although the pace and extent of this expansion remain difficult to predict.
"Encouraged by climate change, travel and international trade, the epidemics of vector-borne diseases (transmitted by insects such as mosquitoes or ticks, Ed) will develop to reach a large part of Europe in the decades to come. come, "they say, at a Congress in Amsterdam.
All countries around the Mediterranean are already concerned, notes Giovanni Rezza, director of the infectious diseases department at the Higher Institute of Health in Rome, interviewed by AFP.
The most worrying recent event is the chikungunya epidemic that hit Italy in the summer of 2017, with "more than 400 cases", and "a failure in early diagnosis", since the disease was only identified by the government after several weeks, favoring the infection of new people, said the researcher.
This task of early identification is all the harder in Italy as the tiger mosquito, which transmits dengue fever and chikungunya, is now endemic in a large part of the country.
Hence the need to strengthen vigilance where the phenomenon is still limited, such as France with Cote d'Azur, where several indigenous cases of dengue have been reported since 2014, insists Dr. Rezza, who presented his conclusions on these issues. recent episodes at the European Congress of Clinical Microbiology and Infectious Diseases, which is being held in Amsterdam until Tuesday.
"Fortunately," Italy, Spain, the south of France, the Croatian coast and Greece are for the moment "a tropical zone only part-time": the winters are cold enough for the transmission to stop. .
– Early warning systems –
But as the periods of high temperature lengthen, this "window" during which these diseases can be transmitted will become wider, favoring epidemics of greater importance, warns Giovanni Rezza, while underlining that it is of "medium to non-short-term change".
The work presented by Jan Semenza of the European Center for Disease Prevention and Control (ECDC), a European agency based in Stockholm, also shows an extension of the territory of ticks, responsible for some viral encephalitis and Lyme disease.
"We are seeing an expansion of ticks caused by higher temperatures, they are developing towards the North and at higher altitudes," he told AFP.
Similarly, the sand fly or sandfly, the main vector of the leishmaniasis parasitic disease, could find favorable climatic conditions for its installation in France, Germany and the southern United Kingdom by 2060.
Faced with this phenomenon, "public health agencies need to improve surveillance, for example through early warning systems, raise awareness among health professionals and the general public about risks, as well as adopt innovative control strategies. such as Community actions "against the proliferation of mosquitoes," emphasizes Professor Semenza.
ECDC is assisting governments in "real-time modeling of climatic conditions for transmission, so that we can increase our attention and monitoring system in these areas," he says.
The European center has thus developed a tool that monitors the temperature and salt content of seawater, illustrated by a map (https://e3geoportal.ecdc.europa.eu/SitePages/Vibrio%20Map%20Viewer.aspx ). The latter makes it possible to identify the beaches most at risk of the presence of bacteria of the vibrio family, responsible for sometimes serious intestinal disorders in humans.