ABSTRACT
The diagnostic criteria for the identification of the various intestinal parasites has been addressed in different ways by a variety of author. This chapter is concerned with identification of what is found in the portion of feces examined. The parasites and eggs found on microscopic examination of human feces usually represent one or more of eight different groups of organisms – four helminth and four protozoa. The helminth parasites include a diverse group of metazoan parasitic animals. The diagnosis of a helminth infection related to the gastrointestinal tract and associated organs is usually made by finding eggs or, less frequently, juvenile nematodes or proglottids of tapeworms in the feces. Passive transmission of the infective stage from either a contaminated source or an infected source is by ingestion. Examples of direct and hand-to-mouth types of transmission are seen in institutions and day care centers where behavioral patterns of the individuals and sanitary control are more conducive to such modes of transmission.
