Pathogenic agents in freshwater resources.
Numerous pathogenic agents have been found in freshwaters used as sources for water supplies, recreational bathing and irrigation.
These agents include bacterial pathogens, enteric viruses, several protozoans and parasitic worms more common to tropical waters.
Although infected humans are a major source of pathogens, farm animals (cattle, sheep, pigs), animal pets (dogs, cats) and wildlife serve as significant reservoirs and should not be ignored.
The range of infected individuals within a given warm-blooded animal group (humans included) may range from 1 to 25%. Survival times for pathogens in the water environment may range from a few days to as much as a year (Ascaris, Taenia eggs), with infective dose levels varying from one viable cell for several primary pathogenic agents to many thousands of cells for a given opportunistic pathogen.
As pathogen detection in water is complex and not readily incorporated into routine monitoring, a surrogate is necessary.
In general, indicators of faecal contamination provide a positive correlation with intestinal pathogen occurrences only when appropriate sample volumes are examined by sensitive methodology.
Pathways by which pathogens reach susceptible water users include ingestion of contaminated water, body contact with polluted recreational waters and consumption of salad crops irrigated by polluted freshwaters.
Major contributors to the spread of various water-borne pathogens are sewage, polluted surface waters a...
Mots-clés Pascal : Microorganisme, Parasite, Pathogène, Milieu eau douce, Qualité eau, Pollution eau, Indicateur biologique, Contamination biologique, Article synthèse, Santé et environnement
Mots-clés Pascal anglais : Microorganism, Parasite, Pathogenic, Freshwater environment, Water quality, Water pollution, Biological indicator, Biological contamination, Review, Health and environment
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 96-0184238
Code Inist : 001D16A04F. Création : 199608.