According to the Department of Preventive Medicine, in Vietnam, 172 species of flies have been identified in residential areas. Of which 70 species of flies are close to home, some species adapt to living near people. The harm of flies to humans and pets:
Reduced livestock productivity
Cattle are bothered by insects continuously during the day. On average, every 10 seconds they have body movements to fight insects, especially flies. They cause livestock itching, discomfort, less sleep leading to reduced weight and performance – reducing productivity, and quality of livestock.
Mediators of disease transmission
According to scientist Derbeneva – Ukhova in 1952, house flies can carry 6 million pathogens on their bodies and in the digestive tract having 28 million pathogens.
Flies have a lot of hairy structure on their legs and proboscis, so they can carry a lot of pathogens. At the same time, they like to eat feces, blood, pus, vomit, feces, garbage, etc. However, pathogens enter their digestive tract not to destroy. In addition, flies also like to eat human foods and live close to people. They eat, vomit, and excrete at the same time, so they cause dirt and pollution, transporting many types of pathogens.
Therefore, house flies are capable of transmitting pathogens such as bacteria such as cholera, bacillus dysentery, tuberculosis, typhoid, etc; viruses such as smallpox, trachoma, hepatitis, polio, etc; parasites such as amoebic dysentery, flagellates, helminth eggs, etc.
Due to the physiological, ecological, and pathogen-transporting characteristics of flies, they become the culprit and one of the important reasons causing the emergence of diseases, especially digest.