See main article: Human parasite.
| Common name of organism or disease | Latin name (sorted) | Body parts affected | Diagnostic specimen | Prevalence | Source/Transmission (Reservoir/Vector) | |
|---|---|---|---|---|---|---|
| Granulomatous amoebic encephalitis and Acanthamoeba keratitis (eye infection) | Acanthamoeba spp. | eye, brain, skin | culture | worldwide | contact lenses cleaned with contaminated tap water | |
| Granulomatous amoebic encephalitis | Balamuthia mandrillaris | brain, skin | culture | worldwide | via inhalation or skin lesion | |
| Babesiosis | Babesia B. divergens, B. bigemina, B. equi, B. microfti, B. duncani | red blood cells | Giemsa-stained thin blood smear | New England (different species have worldwide distribution) | tick bites, e.g. Ixodes scapularis | |
| Balantidiasis | Balantidium coli | intestinal mucosa, may become invasive in some patients | stool (diarrhea=ciliated trophozoite; solid stool=large cyst with horseshoe shaped nucleus) | ingestion of cyst, zoonotic infection acquired from pigs (feces) | ||
| Blastocystosis | Blastocystis spp. | intestinal | direct microscopy of stool (PCR, antibody) | worldwide: one of the most common human parasites Developing regions: infects of the total populations[1] [2] [3] | eating food contaminated with feces from an infected human or animal | |
| Cryptosporidiosis | Cryptosporidium spp. | intestines | stool | widespread | ingestion of oocyst (sporulated), some species are zoonotic (e.g. bovine fecal contamination) | |
| Cyclosporiasis | Cyclospora cayetanensis | intestines | stool | United States | ingestion of oocyst through contaminated food | |
| Dientamoebiasis | Dientamoeba fragilis | intestines | stool | up to 10% in industrialized countries | ingesting water or food contaminated with feces | |
| Amoebiasis | Entamoeba histolytica | intestines (mainly colon, but can cause liver failure if not treated) | stool (fresh diarrheic stools have amoeba, solid stool has cyst) | areas with poor sanitation, high population density and tropical regions | fecal-oral transmission of cyst, not amoeba | |
| Giardiasis | Giardia lamblia | lumen of the small intestine | stool | worldwide? | ingestion of water containing deer or beaver feces | |
| Isosporiasis | Isospora belli | epithelial cells of small intestines | stool | worldwide – less common than Toxoplasma or Cryptosporidium | fecal oral route – ingestion of sporulated oocyst | |
| Leishmaniasis | Leishmania spp. | cutaneous, mucocutaneous, or visceral | visual identification of lesion or microscopic stain with Leishman's or Giemsa's stain | visceral leishmaniasis – worldwide; cutaneous leishmaniasis – Old World; mucocutaneous leishmaniasis – New World | Phlebotomus, Lutzomyia – bite of several species of phlebotomine sandflies | |
| Primary amoebic meningoencephalitis (PAM)[4] [5] | Naegleria fowleri | brain | culture | unknown, but infection is rare | nasal insufflation of contaminated warm fresh water, poorly chlorinated swimming pools, hot springs, soil | |
| Malaria | Plasmodium falciparum (80% of cases), Plasmodium vivax, Plasmodium ovale curtisi, Plasmodium ovale wallikeri, Plasmodium malariae, Plasmodium knowlesi | red blood cells, liver | blood film | tropical – 250 million cases/year | Anopheles mosquito | |
| Rhinosporidiosis | Rhinosporidium seeberi | nose, nasopharynx | biopsy | India and Sri Lanka | nasal mucosa came into contact with infected material through bathing in common ponds | |
| Sarcocystosis | Sarcocystis bovihominis,Sarcocystis suihominis | intestine, muscle | muscle biopsy | widespread | ingestion of uncooked/undercooked beef/pork with Sarcocystis sarcocysts | |
| Toxoplasmosis (Acute and Latent) | Toxoplasma gondii | eyes, brain, heart, liver | blood and PCR | worldwide: one of the most common human parasites; estimated to infect between of the global population.[6] [7] | ingestion of uncooked/undercooked pork/lamb/goat with Toxoplasma bradyzoites, ingestion of raw milk with Toxoplasma tachyzoites, ingestion of contaminated water food or soil with oocysts in cat feces that is more than one day old | |
| Trichomoniasis | Trichomonas vaginalis | female urogenital tract (males asymptomatic) | microscopic examination of genital swab | worldwide | sexually transmitted infection – only trophozoite form (no cysts) | |
| Sleeping sickness | Trypanosoma brucei | brain and blood | microscopic examination of chancre fluid, lymph node aspirates, blood, bone marrow | 50,000 to 70,000 people; only found in Africa | tsetse fly, day-biting fly of the genus Glossina | |
| Chagas disease | Trypanosoma cruzi | colon, esophagus, heart, nerves, muscle and blood | Giemsa stain – blood | Mexico, Central America, South America – 16–18 million | Triatoma/Reduviidae – "kissing bug" insect vector, feeds at night |
Helminth organisms (also called helminths or intestinal worms) include:
| Common name of organism or disease | Latin name (sorted) | Body parts affected | Diagnostic specimen | Prevalence | Transmission/Vector | |
|---|---|---|---|---|---|---|
| Tapeworm – Tapeworm infection | Cestoda, Taenia multiceps | intestine | stool | rare worldwide | ||
| Diphyllobothriasis – tapeworm | Diphyllobothrium latum | intestines, blood | stool (microscope) | Europe, Japan, Uganda, Peru, Chile | ingestion of raw fresh water fish | |
| Diphyllobothriasis – tapeworm | Diphyllobothrium pacificum | intestines | stool (microscope) | Peru | ingestion of raw saltwater fish | |
| Echinococcosis – tapeworm | Echinococcus granulosus, Echinococcus multilocularis, E. vogeli, E. oligarthrus | liver, lungs, kidney, spleen | imaging of hydatid cysts in the liver, lungs, kidney and spleen | Worldwide in grazing areas | as intermediate host, ingestion of material contaminated by feces from a carnivore; as definite host, ingestion of uncooked meat (offal) from a herbivore | |
| Hymenolepiasis[8] | Hymenolepis nana, Hymenolepis diminuta | ingestion of material contaminated by flour beetles, mealworms, cockroaches | ||||
| Beef tapeworm | Taenia saginata | Intestines | stool | worldwide distribution | ingestion of undercooked beef | |
| Cysticercosis-Pork tapeworm | Taenia solium | Brain, muscle, Eye (Cysts in conjunctiva/anterior chamber/sub-retinal space) | stool, blood, imaging of cysts in the brain or any soft tissue | Asia, Africa, South America, Southern Europe, North America. | as definite host: ingestion of undercooked pork; as intermediate host, ingestion of material contaminated by human feces from a person carrying the adult form | |
| Bertielliasis | Bertiella mucronata, Bertiella studeri | Intestines | stool | rare | contact with non-human primates | |
| Sparganosis | Spirometra erinaceieuropaei | ingestion of material contaminated with infected dog or cat feces (humans: dead-end host) |
| Common name of organism or disease | Latin name (sorted) | Body parts affected | Diagnostic specimen | Prevalence | Transmission/Vector | |
|---|---|---|---|---|---|---|
| Clonorchiasis | Clonorchis sinensis
| gall bladder ducts and inflammation of liver | East Asia | ingestion of under prepared freshwater fish | ||
| Lancet liver fluke | Dicrocoelium dendriticum | gall bladder | rare | ingestion of ants | ||
| Liver fluke – Fasciolosis | Fasciola hepatica, Fasciola gigantica | liver, gall bladder | stool | Fasciola hepatica in Europe, Africa, Australia, the Americas and Oceania; Fasciola gigantica only in Africa and Asia, 2.4 million people infected by both species | freshwater snails | |
| Fasciolopsiasis – intestinal fluke[9] | Fasciolopsis buski | intestines | stool or vomitus (microscope) | East Asia – 10 million people | ingestion of infested water plants or water (intermediate host:amphibic snails) | |
| Metagonimiasis – intestinal fluke | Metagonimus yokogawai | stool | Siberia, Manchuria, Balkan states, Israel, Spain | ingestion of undercooked or salted fish | ||
| Metorchiasis | Metorchis conjunctus | Canada, US, Greenland | ingestion of raw fish | |||
| Chinese liver fluke | Opisthorchis viverrini, Opisthorchis felineus, Clonorchis sinensis | bile duct | 1.5 million people in Russia | consuming infected raw, slightly salted or frozen fish | ||
| Paragonimiasis, lung fluke | Paragonimus westermani
| lungs | sputum, feces | East Asia | ingestion of raw or undercooked freshwater crabs crayfishes or other crustaceans | |
| Schistosomiasis – bilharzia, bilharziosis or snail fever (all types) | Schistosoma sp. | Africa, Caribbean, eastern South America, east Asia, Middle East – 200 million people | skin exposure to water contaminated with infected freshwater snails | |||
| intestinal schistosomiasis | Schistosoma mansoni and Schistosoma intercalatum | intestine, liver, spleen, lungs, skin, rarely infects the brain | stool | Africa, Caribbean, South America, Asia, Middle East – 83 million people | skin exposure to water contaminated with infected Biomphalaria freshwater snails | |
| urinary blood fluke | Schistosoma haematobium | kidney, bladder, ureters, lungs, skin | urine | Africa, Middle East | skin exposure to water contaminated with infected Bulinus sp. snails | |
| Schistosomiasis by Schistosoma japonicum | Schistosoma japonicum | intestine, liver, spleen, lungs, skin | stool | China, East Asia, Philippines | skin exposure to water contaminated with infected Oncomelania sp. snails | |
| Asian intestinal schistosomiasis | Schistosoma mekongi | South East Asia | skin exposure to water contaminated with infected Neotricula aperta – freshwater snails | |||
| Echinostomiasis | Echinostoma echinatum | small intestine | Far East | ingestion of raw fish, mollusks, snails | ||
| Swimmer's itch | Trichobilharzia regenti, Schistosomatidae | worldwide | skin exposure to contaminated water (snails and vertebrates) |
| Disease caused | Latin name (sorted) | Habitat in definite host | Diagnostic Sample | Prevalence | Mode of transmission | |
|---|---|---|---|---|---|---|
| Ancylostomiasis/Hookworm | Ancylostoma duodenale, Necator americanus | lungs, small intestine, blood | stool | common in tropical, warm, moist climates | penetration of skin by L3 larva | |
| Angiostrongyliasis | Angiostrongylus | intestine | stool | ingestion of infected faeces or infected slugs | ||
| Anisakiasis[10] | Anisakis | allergic reaction | biopsy | incidental host | ingestion of raw fish, squid, cuttlefish, octopus | |
| Roundworm – Parasitic pneumonia | Ascaris sp. Ascaris lumbricoides | Intestines, liver, appendix, pancreas, lungs, Löffler's syndrome | stool | common in tropical and subtropical regions | ||
| Roundworm – Baylisascariasis | Baylisascaris procyonis | Intestines, liver, lungs, brain, eye | rare: North America | stool from raccoons | ||
| Roundworm-lymphatic filariasis | Brugia malayi, Brugia timori | lymph nodes | blood samples | tropical regions of Asia | arthropods | |
| Dioctophyme renalis infection | Dioctophyme renale | kidneys (typically the right) | urine | rare | ingestion of undercooked or raw freshwater fish | |
| Ophidascaris robertsi infection | Ophidascaris robertsi | brain | newly discovered infection[11] [12] | Single reported case was likely due to ingestion of gathered wild plants, contaminated with feces from pythons | ||
| Guinea worm – Dracunculiasis | Dracunculus medinensis | subcutaneous tissues, muscle | skin blister/ulcer | South Sudan (eradication ongoing) | ||
| Pinworm – Enterobiasis | Enterobius vermicularis, Enterobius gregorii | intestines, anus | stool; tape test around anus | widespread; temperate regions | ||
| Gnathostomiasis[13] | Gnathostoma spinigerum, Gnathostoma hispidum | subcutaneous tissues (under the skin) | physical examination | rare – Southeast Asia | ingestion of raw or undercooked meat (e.g., freshwater fish, chicken, snails, frogs, pigs) or contaminated water | |
| Halicephalobiasis | Halicephalobus gingivalis | brain | soil-contaminated wounds | |||
| Loa loa filariasis, Calabar swellings | Loa loa filaria | connective tissue, lungs, eye | blood (Giemsa, haematoxylin, eosin stain) | rain forest of West Africa – 12–13 million people | Tabanidae – horsefly, bites in the day | |
| Mansonelliasis, filariasis | Mansonella streptocerca | subcutaneous layer of skin | insect | |||
| River blindness, onchocerciasis | Onchocerca volvulus | skin, eye, tissue | bloodless skin snip | Africa, Yemen, Central and South America near cool, fast flowing rivers | Simulium/black fly, bites during the day | |
| Strongyloidiasis – Parasitic pneumonia | Strongyloides stercoralis | intestines, lungs, skin (Larva currens) | stool, blood | skin penetration | ||
| Thelaziasis | Thelazia californiensis, Thelazia callipaeda | eyes | ocular examination | Asia, Europe | Amiota (Phortica) variegata, Phortica okadai | |
| Toxocariasis | Toxocara canis, Toxocara cati, Toxascaris leonina | liver, brain, eyes (Toxocara canis – visceral larva migrans, ocular larva migrans) | blood, ocular examination | worldwide distribution | pica, unwashed food contaminated with Toxocara eggs, undercooked livers of chicken | |
| Trichinosis | Trichinella spiralis, Trichinella britovi, Trichinella nelsoni, Trichinella nativa | muscle, periorbital region, small intestine | blood | more common in developing countries due to improved feeding practices in developed countries. | ingestion of undercooked pork | |
| Whipworm | Trichuris trichiura, Trichuris vulpis | large intestine, anus | stool (eggs) | common worldwide | accidental ingestion of eggs in dry goods such as beans, rice, and various grains or soil contaminated with human feces | |
| Elephantiasis – Lymphatic filariasis | Wuchereria bancrofti | lymphatic system | thick blood smears stained with hematoxylin. | tropical and subtropical | mosquito, bites at night |
| Common name of organism or disease | Latin name (sorted) | Body parts affected | Diagnostic specimen | Prevalence | Transmission/Vector | |
|---|---|---|---|---|---|---|
| Acanthocephaliasis | Archiacanthocephala, Moniliformis moniliformis | Gastrointestinal tract, peritoneum, eye | Faeces, parasite itself | worldwide | ingestion of intermediate hosts | |
| Halzoun syndrome | Linguatula serrata | nasopharynx | physical examination | Mid East | ingestion of raw or undercooked lymph nodes (e.g., meat from infected camels and buffaloes) | |
| Myiasis | Oestroidea, Calliphoridae, Sarcophagidae | dead or living tissue | ||||
| Screwworm, Cochliomyia | Cochliomyia hominivorax (family Calliphoridae) | skin and wounds | visual | North America (eradicated), Central America, North Africa | direct contact with fly | |
| Chigoe flea | Tunga penetrans | Subcutaneous tissue | physical examination | Central and South America, Sub-Saharan Africa | ||
| Human botfly | Dermatobia hominis | Subcutaneous tissue | physical examination | Central and South America | mosquitoes and biting flies |
| Common name of organism or disease | Latin name (sorted) | Body parts affected | Diagnostic specimen | Prevalence | Transmission/Vector | |
|---|---|---|---|---|---|---|
| Head louse – Pediculosis | Pediculus humanus capitis | hair follicles | visual identification under magnification | common worldwide | head-to-head contact | |
| Body louse – Pediculosis | Pediculus humanus humanus | skin | visual identification under magnification (Vagabond's disease) | common worldwide | skin-to-skin contact such as sexual activity and via sharing clothing or bedding | |
| Crab louse –Phthiriasis | Pthirus pubis | pubic area, eyelashes | visual identification under magnification | common worldwide | skin-to-skin contact such as sexual activity and via sharing clothing or bedding | |
| "Chiggers" (Trombiculidae) – Trombiculosis | Arachnida: Trombiculidae | skin | visual identification under magnification, microscopy | worldwide (mesic habitats) | high grass, weeds | |
| Flea | Siphonaptera | skin | visual identification under magnification | worldwide | environment | |
| Bed bug | Cimicidae: Cimex lectularius and Cimex hemipterus | skin | visual | worldwide | clothing, bedding, personal possessions | |
| Tick | Arachnida: Ixodidae and Argasidae | skin | visual | worldwide | high grass, leaf litter, weeds | |
| Mosquito | Insecta: Diptera | skin | visual | worldwide | high grass, weeds | |
| Demodex – Demodicosis | Demodex folliculorum/brevis/canis | eyebrow, eyelashes, skin, face, scalp | microscopy of eyelash or eyebrow hair follicle, cellophane tape method (CTP), squeezing method, skin scrapings | pandemic, worldwide | Commensal, prolonged skin-to-skin contact | |
| Scabies | Sarcoptes scabiei | skin | microscopy of surface scrapings | worldwide | skin-to-skin contact such as sexual activity and via sharing clothing or bedding | |
| Red mite — Gamasoidosis | Dermanyssus gallinae | skin | visual identification under magnification | worldwide | nesting birds, pets, poultry farming | |
| Northern fowl mite — Gamasoidosis | Ornithonyssus sylviarum | skin | visual identification under magnification | worldwide | nesting birds, poultry farming | |
| Tropical fowl mite — Gamasoidosis | Ornithonyssus bursa | skin | visual identification under magnification | worldwide | nesting birds, poultry farming | |
| Tropical rat mite — Rodent mite dermatitis | Ornithonyssus bacoti | skin | visual identification under magnification | worldwide | rodent infestations | |
| Spiny rat mite — Rodent mite dermatitis | Laelaps echidnina | skin | visual identification under magnification | worldwide | rodent infestations | |
| House mouse mite — Rodent mite dermatitis | Liponyssoides sanguineus | skin | visual identification under magnification | worldwide | rodent infestations |