After the scourge of the tiger mosquito, that of the black fly? Since the beginning of August, the Spanish health authorities have been on alert. An insect could well spoil the holidays of travelers in Iberian territory. On August 5, the National Association of Environmental Health Societies (Anecpla) announced that the population of black flies, “musca negra”, has exploded in recent years. The insect would have already proliferated everywhere in Spain, “from Madrid to Valencia via Andalusia”, indicates the prestigious daily El Mundo.
In recent days, the association Anecpla has flooded the Spanish media with alerts and recommendations, indicating that more and more people are falling victim to the black fly (Simuliidae, its scientific name). “The bite of the black fly, a seasonal danger”, thus headlined the newspaper National Geographic Spain. But what is the black fly? Is she dangerous? Is its proliferation possible in France? The Express takes stock.
A fly that bites
If its mass appearance seems to surprise the Spanish health authorities, this species of fly is actually present throughout Europe according to Christophe Daugeron, researcher from the joint research unit (UMR) Mecadev for the Natural History Museum. “It is a species very widely distributed throughout the northern hemisphere, which likes the heat, and always appears in the summer period, from April until around August”. It has been widely observed in the Danube basin and in Eastern Europe. And the researcher to specify: “It is a fly which occupies environments close to water because its larvae are aquatic.”
Also, one of the peculiarities of this fly is that it bites. “The females indeed take a blood sample because they need it for the maturation of their eggs”, explains Christophe Daugeron. In humans, as in farm animals, these bites can cause an allergic reaction. “It is important to consult a pharmacist immediately if this happens,” comments the researcher from the Natural History Museum. “Another problem, the bite usually results in a fairly large wound. A wound with segments, and therefore with a risk of infection, which must therefore be disinfected quickly”. The bite can cause fever, nausea, headache, itching or swelling, however, the harm caused remains less. “Among blackflies, there are a few species that can transmit onchocerciasis (a disease that can cause blindness), to humans and cattle. This has already been observed in Eastern Europe, and in Africa, but not in Western Europe”, reassures Christophe Daugeron. According to our colleagues from Parisianwho cite several scientists, no human deaths linked to the black fly have been recorded in the past century.
An unusual proliferation linked to global warming?
Several articles in the Spanish press, including El Mundo, argue that the unusual massive proliferation of this fly in the country is linked to temperatures, particularly in recent summer seasons, due to global warming. “For many species, the higher the temperatures, the more cycles there are in a season, indicates Christophe Daugeron. When the weather is particularly favorable, we observe more flies, it is because the cycles are more numerous. , and shortened because the development of eggs and larvae is faster”.
In total, there are nearly 1,500 black fly families around the world, including 400 in Europe and 70 in France. For the time being, no bite from this species of black fly has been recorded in France.