Salvador Dalí was fascinated by the “clean flies” – that’s what he called them – that flew among the olive trees of Port Lligat, the small Catalan coastal town where he lived for many years. So much so that, when he painted, he put honey on the corners of his lips so that these flying insects would come to alight on him. He differentiated them from the “dirty flies” of the city, repugnant in his opinion.
The artist was somewhat right in his visceral hatred of urban flies. A work published in the journal Scientific Reports reveals that flies and blowflies carry hundreds of species of pathogenic microorganisms potentially dangerous to health in their bodies. And he adds that the specimens that live in the cities are richer in this harmful baggage than those in the countryside or the farm stables.
Flying transports of pathogens
An international team of researchers has studied the microbiomes of 116 flies and blowflies from three continents and varied environments, and has found that hundreds of species of disease-causing microorganisms live in many of them, including Helicobacter pylori, a bacterium that can cause ulcers. and even stomach cancer. Scientists think that this microorganism is transmitted through contaminated water and food, but flies have not been documented until now as a vector of the dangerous pathogen.
These insects have long been known to promote the spread of infections, but work published in Scientific Reports delves into how the process occurs. For example, the use of scanning electron microscopes has found that the legs are the part of your body that transfers most microbes from one surface to another. The wings are another appendix that presents great microbial diversity. The flies act as shuttles for pathogens, taking them from one place to another without charging them a ticket.
They do not disgust anything
These flying insects belonging to the order of Diptera are the first to reach corpses, decomposing organic matter and feces, where they feed and lay their eggs. It is there where they acquire most of the microorganisms that they later transport through the air to deposit them in hosts such as humans, animals and plants.
Flies and blowflies, given their ubiquity and ease of movement, play an important role in the dispersal of pathogenic microbes through urban and natural environments. Donald Bryant, from Penn State University (United States) and director of this research, considers that “flies can help the rapid transmission of pathogens during infectious outbreaks”, and thinks that health authorities should consider this possibility.
But not everything is bad in these insects. Researchers believe that we can use them to our advantage. If they are released somewhere, they will feed on the carrion in the area and acquire a complete sample of the microorganisms from it. Capturing them and analyzing them later would serve to detect the presence of local pathogens that could trigger disease, and to control them before they spread.
