What are the features of the life of a leech?

Leeches live in fresh water. These can be natural and artificial reservoirs: lakes, ponds and others. Leeches attach themselves to animals and drink blood. They can attach to fish, mammals that enter the water. They are used by people in alternative medicine. They are able to positively influence the injured skin areas. They cannot harm a person. But there are still risks that microorganisms from a polluted reservoir will get into the wound after a bite and this can cause illness.