2024-07-10 16:49:12
The Olympic Games in Paris start on July 26. In advance, French scientists warn of an epidemic.
The Asian tiger mosquito is becoming a problem in more and more countries. The US health authority recently warned of the spread of the dengue virus transmitted by it in their own country. A record number of infections are currently being reported worldwide. Read more about this here.
Europe is also affected, and with it France. By the end of April there were 1,679 infections. By comparison, in the same period last year only 131 infections were recorded, meaning that there have been almost 13 times as many cases in 2024 so far.
In just over two weeks, the Olympic Games will start in Paris, and eleven million visitors from all over the world are expected to come to the French capital. In advance, a study by the Institut Pasteur (the French equivalent of the German Robert Koch Institute) has raised alarm. It warns of a possible epidemic.
Researchers from the institute caught tiger mosquitoes in Paris and analyzed which viruses they carry. The result: Five different types of viruses can be transmitted by the insect. In addition to dengue fever, these include West Nile fever, Chikungunya, Zika and Usutu viruses. The latter is a largely unknown virus that originates from Africa and mainly affects birds. But infection can also lead to serious symptoms in humans, including encephalitis.
The scientists now investigated how quickly the viruses multiply. The background: Whether a mass infection develops into an epidemic depends largely on the duration of the multiplication cycle. The longer it is, the better, because the easier it is to break the chain of infection.
West Nile fever was the fastest to multiply in the laboratory. At 28 degrees, an average summer temperature, it would only take three days for the virus to be passed from mosquito to human. This means that a massive spread would only take a few days. The incubation period for Chikungunya and Usutu viruses was three to seven days, and for Dengue and Zika viruses it was 14 to 21 days.
Study leader Anna-Bella Failloux and her team see their analysis as a call for vigilance. Visitors to the Olympic Games also come from regions where these viruses are partly endemic. The mosquitoes could therefore spread them.
However, mosquitoes need moisture (standing water, puddles, etc.) to reproduce. If it remained largely dry, the risk of virus transmission and spread would be lower.