Manual of basic techniques for a health laboratory - libdoc.who.int

106 Manual of basic techniques for a health laboratoryIt is useful for laboratory technicians to understand the ways in which people canbecome infected by intestinal parasites (see Table 4.2). They can then give adviceon hygiene to members of the community and avoid infection themselves, particularlyin the laboratory.Table 4.2 Routes of transmission of intestinal parasitesScientific name Common name How infection is contractedHelminthsAncylostoma duodenale Hookworm Walking barefoot on ground contaminated by stools; playing oncontaminated ground (children)Ascaris lumbricoides Roundworm, ascaris Eating unwashed raw vegetables and salads; playing on groundcontaminated by stools (children)Clonorchis sinensis Chinese liver fluke Eating undercooked infected meatDicrocoelium dendriticum, Lancet fluke Swallowing infected ants (in unwashed salad or while playing inD. hospes grass (children))Diphyllobothrium latum Fish tapeworm Eating raw or undercooked freshwater fishDipylidium caninum Dog tapeworm Swallowing dog fleas (children)Enterobius vermicularis Pinworm, threadworm Walking barefoot on ground contaminated by stools;autoinfection; contact with infected persons with dirty hands;failure to observe safety regulations relating to cleanliness inthe laboratoryFasciola gigantica Giant liver fluke Eating unwashed saladsFasciola hepatica Liver fluke Eating unwashed saladsFasciolopsis buski Giant intestinal fluke Eating unwashed saladsHeterophyes heterophyes Dwarf fluke Eating undercooked infected meatHymenolepis diminuta Rat tapeworm Swallowing rat fleasHymenolepis nana Dwarf tapeworm Eating contaminated vegetables; autoinfectionMetagonimus yokogawai Japanese fluke Eating undercooked infected meatNecator americanus Hookworm Walking barefoot on ground contaminated by stools; playing oncontaminated ground (children)Paragonimus westermani Oriental lung fluke Eating undercooked infected freshwater crabsSchistosoma haematobium Schistosome (vesical) Bathing in streams or ponds contaminated by infected stools orurineSchistosoma intercalatum Schistosome (rectal) Bathing in streams or ponds contaminated by infected stools orurineSchistosoma japonicum Schistosome (Asiatic Bathing in streams or ponds contaminated by infected stools oror Oriental)urineSchistosoma mansoni Schistosome (intestinal) Bathing in streams or ponds contaminated by infected stools orurineTaenia saginata Beef tapeworm Eating undercooked infected meatTaenia solium:Pork tapeworm— adults Eating undercooked infected meat— larval form (cysticercus) Eating unwashed raw vegetables; autoinfectionTrichostrongylus spp. — Eating unwashed salads (Asia)Trichuris trichiura Whipworm Eating unwashed raw vegetables and saladsProtozoaBalantidium coli — Eating unwashed vegetables; contact with infected pigs (onfarms)Entamoeba histolytica — Drinking contaminated water; eating unwashed raw vegetablesand salads; contact with infected persons with dirty hands;failure to observe safety regulations relating to cleanliness inthe laboratoryGiardia intestinalis — Drinking contaminated water; eating unwashed raw vegetablesand salads; contact with infected persons with dirty hands;failure to observe safety regulations relating to cleanliness inthe laboratory