The house fly along with the blowfly collectively harbour over 600 different bacteria, according to a DNA analysis.
Many are linked with human ailments, including stomach bugs, blood poisoning and pneumonia.
Flies can spread germs from place-to-place on their legs, feet and wings, experiments reveal. In fact, every measure taken by a fly may move live bacteria, researchers said.
“People had some idea that there were pathogens which were carried by flies but had no idea of the extent to which this is true and also the extent to which they’re moved,” Prof Donald Bryant of Penn State University, a co-researcher on the study, told BBC News.
DNA sequencing techniques were utilized to study the selection of germs found in and on the bodies of the house fly (Musca domestica) and the blowfly (Chrysomya megacephala).
The house fly, which is ubiquitous around the world, was discovered to harbor 351 kinds of bacteria. The blowfly, that is found in warmer climates, carried 316. A high number of those bacteria were carried by the two types of fly.
The researchers, who published their research in the journal Scientific Reports, say flies might have been overlooked by public health officials as a source of disease outbreaks.
“We believe that this may show a mechanism for pathogen transmission that has been overlooked by public health officials, and flies may add to the speedy transmission of pathogens in outbreak situations,” said Prof Bryant.
However, the researchers believe flies could have their uses – acting as early warning systems for illness or even living drones delivered into tight spaces to search for microbes.
“In fact, the flies could be intentionally released as sovereign bionic drones into even the smallest spaces and crevices and, upon being recaptured, notify about any biotic material they have struck,” stated Stephan Schuster, study director at Nanyang Technological University, Singapore.
House flies are well known for their poor hygiene habits – visiting garbage piles and feeding on all kinds of decaying food, animal corpses and faecal matter. They’re suspected of carrying a variety of human, plant and animal diseases.
Blow flies are one of the most common flies found around dead creatures. They are common in urban areas and tend to be found near meat-processing plants, rubbish dumps and slaughterhouses.