Muscina - Medical Importance

Medical Importance

Some insects have been shown to be potential carriers of pathogenic agents that can cause diseases. Mosquitoes and ticks as well as certain species of Muscina flies have been revealed to be possible vectors. M. stabulans, along with almost two dozen other species of flies have been named the “disease-causing flies.” Species of flies such as M. stabulans can spread bacterial and viral pathogens via transfer from its feet or mouthparts. Adult female flies tend to lay eggs in decaying material such as food or dead organisms and fresh fecal material. The fecal material houses a vast number of pathogenic bacteria, viruses, protozoan and other disease-causing agents. Most of the bacteria and viruses are not introduced from the fecal material to the fly when in the egg or larvae form; rather, the transfer occurs in the transition of a young fly to adulthood. Fecal particles attach to the fly’s outer body as it emerges from the larvae. Transfer of bacteria occurs when the fly takes off and lands on an open wound or food material. Physical contact flakes the pathogen off the fly's body and causes contamination. The spread of a pathogen by means of a fly’s outer body, such as its feet, to the host, is referred to as mechanical transmission. It is possible to determine the identify pathogen carried by identifying the species of fly. In these instances, food sanitation is an important preventive measure to ensure food safety. Moreover, a study of flies including M. stabulans and M. levida has shown that fly incidence peaked about 4–5 months before the occurrence of a poliomyelitis epidemic. This time period matches the time it takes for the infective agent to incubate in a human plus the extra time necessary for the fly to acquire and incubate the virus in its body.