pathogens

A virus, bacterium or parasite which causes disease is a pathogenpathogens A virus, bacterium or parasite which causes disease is a pathogen. Disease causing pathogens live in the environment, and both humans and animals are hosts to them. Pathogenic viruses, bacteria and parasites are present in sewage, originating from humans and animals, and thus it is essential that sewage is given proper treatment in order to disable (kill) these pathogens before the end-products of sewage treatment (solids and water effluent) are returned to the environment.. Disease causing pathogenspathogens A virus, bacterium or parasite which causes disease is a pathogen. Disease causing pathogens live in the environment, and both humans and animals are hosts to them. Pathogenic viruses, bacteria and parasites are present in sewage, originating from humans and animals, and thus it is essential that sewage is given proper treatment in order to disable (kill) these pathogens before the end-products of sewage treatment (solids and water effluent) are returned to the environment. live in the environment, and both humans and animals are hosts to them. Pathogenic viruses, bacteria and parasites are present in sewage, originating from humans and animals, and thus it is essential that sewage is given proper treatment in order to disable (kill) these pathogens before the end-products of sewage treatment (solids and water effluent) are returned to the environment.