fecal-oral route

Many diseases can be passed when fecal particles from one host are introduced into the mouth of another potential host. This is referred to as the fecal-oral route (or alternatively, the oral-fecal route or orofecal route). There are, usually, intermediate steps, sometimes many of them. Amongst the more common causes are: Water that has come in contact with feces and poorly treated before drinking; food that has been handled with feces present; poor sewage treatment; poor or absent cleaning after handling feces or anything that has been in contact with feces.
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