Nematodes & cestodes

lab portion

Enterobius vermicularis

Enterobius vermicularis disease name

pinworm

Enterobius vermicularis diagnostic stage

unembryonated eggs in feces

Enterobius vermicularis infective stage

embryonated eggs

#1 worm infection in USA

Enterobius vermicularis

Trichuris trichiura

Trichuris trichiura disease name

whipworm, trichuriasis

Trichuris trichiura infective stage

embryonated eggs

Trichuris trichiura diagnostic stage

unembryonated eggs in feces

3rd most common intestinal helminth

Trichuris trichiura

Ascaris lumbricoides

Ascaris lumbricoides disease name

large intestinal roundworm

Ascaris lumbricoides infective stage

eggs with fully developed larvae

Ascaris lumbricoides diagnostic stage

unembryonated eggs in feces

Decorticated Eggs

eggs that lack thick albuminous coating

2nd most common infection in the USA

Ascaris lumbricoides

Largest nematode

Female Ascaris lumbricoides worm

Necator americanus/ancylostoma duodenale egg

Necator americanus disease name

new world hookworm

Necator americanus diagnostic stage

embryonated eggs

Necator americanus infective stage

larva (filariform)

cutting plates in mouth

Necator americanus morphology (larva)

hookworm rhabditiform larvae

long buccal cavity, short esophagus

Trichuris trichiura double infects with

ascaris lumbricoides

Ancylostoma duodenale disease name

old world hookworm

4 teeth in mouth

Ancylostoma duodenale morphology (larva)

short buccal cavity, long esophagus

Strongyloides stercolaris

Strongyloides stercolaris disease name

threadworm

Strongyloides stercolaris diagnostic stage

rhabditiform larvae

Strongyloides stercolaris infective stage

filariform larvae

Trichinella spiralis

Trichinella spiralis disease name

Trichinosis

Trichinella spiralis transmission

ingestion of undercooked striated muscle containing larvae in pork

Trichinella spiralis diagnostic stage

encysted larvae in striated muscle

Dracunculus medinensis

Dracunculus medinensis disease name

guinea worm

Dracunculus medinensis diagnostic stage

emerging worms release larvae from skin ulcer

Dracunculus medinensis infective stage

copepod

Largest adult nematode parasite in humans

Dracunculus medinensis

Wuchereria bancrofti 

Wuchereria bancrofti disease name

Bancroft’s filaria, elephantiasis

Wuchereria bancrofti diagnostic stage

microfilariae in blood

Wuchereria bancrofti infective stage

larvae in arthropod (intermediate host)

Wuchereria bancrofti morphology

no nuclei in tail tip 

Wuchereria bancrofti arthropod hosts

Culex, Aedes, Anopheles mosquitoes

Brugia malayi

Brugia malayi disease name

malayan filariasis

Brugia malayi diagnostic stage

microfilariae in blood

Brugia malayi morphology

sheathed, tightly coiled, terminal and subterminal nuclei at tail (two swellings)

Loa loa

Loa loa disease name

eyeworm

Loa loa diagnostic stage

microfilariae in blood; migrate through conjuctiva of the eye

Loa loa morphology

sheathed, coiled, nuclei extends to tail

small, no sheath, blunt tail with nuclei extending to end of tailL

Mansonella perstans morphology

Loa loa host

deer fly

Brugia malayi arthropod host

Mansonia, Anopheles mosquito

Onchocerca volvulus

Onchocerca volvulus disease name

blinding filaria, river blindness

Onchocerca volvulus diagnostic stage

microfilariae in dermis

Onchocerca volvulus arthropod host

Simulium, blackfly

Onchocerca volvulus morphology

no sheath, nuclei not terminal, curved tail

Onchocerca volvulus transmission

adult filariae in subcutaneous tissue

Hymenolepis nana

Hymenolepis nana disease name

dwarf tapeworm

Hymenolepis nana diagnostic stage

eggs in feces

Hymenolepis nana infective stage

released egg (no intermediate host required)

Most prevalent tapeworm found throughout the United States

Hymenolepis nana

Taenia saginata disease name

Taeniasis, beef tapeworm

Taenia solium disease name

pork tapeworm

Taenia sp. diagnostic stage

free eggs or gravid proglottids

Taenia sp. infective stage

cysticercus larava

Taenia saginata intermediate host

cow

Taenia solium intermediate host

pig

15-20 branches on each side

Taenia saginata proglottids

7-13 branches on each side

Taenia solium proglottids

Taenia sp. egg

4 suckers, no hooks

Taenia saginata scolex

4 suckers, double row of hooks

Taenia solium scolex

Diphyllobothrium latum

Diphyllobothrium latum disease name

broadfish tapeworm

Diphyllobothrium latum transmission

ingested by human in raw or undercooked freshwater fish

Diphyllobothrium latum diagnostic stage

undeveloped egg passed in feces

broader than long

Diphyllobothrium latum proglottid

what can grow up to 20 meters long in the intestine

Diphyllobothrium latum

Echinococcus granulosus

Echinococcus granulosus disease name

Hydatid tapeworm

Echinococcus granulosus diagnostic stage

hydatid cyst in liver, lung, or other organ

Leak of hydatid cyst can lead to

anaphylaxis

Echinococcus granulosus affinitive host

human; most commonly in canines

Hymenolepis diminuta

Hymenolepsis diminuta disease name

rat tapeworm

Hymenolepsis diminuta transmission

human ingests cysticercoid larva in infected flea or grain beetle

Dipylidium caninum

Dipylidium caninum intermediate host

dog/cat flea

wuchereria bancrofti

loa loa

brugia malayi

onchocerca volvulus

mansonella perstans