CLASS TREMATODA (FLUKES)CLASS TREMATODA (FLUKES) CharacteristicsCharacteristics

Dorsoventrally flattened EXCEPT SchistosomaDorsoventrally flattened EXCEPT Schistosoma Have 2 suckersHave 2 suckers

Oral and ventral suckers for attachmentOral and ventral suckers for attachment Life cycleLife cycle

Egg – operculted ova EXCEPT for SchistosomaEgg – operculted ova EXCEPT for SchistosomaLarvaLarva

Miracidium->sporocyst->redia->Miracidium->sporocyst->redia->

cercaria->metacercariacercaria->metacercariaadultadult

Definitive host: ManDefinitive host: ManHarbors adult wormHarbors adult wormInfective stage: metacercaria Infective stage: metacercaria

EXCEPT SchistosomaEXCEPT Schistosoma

Manner of transmissionManner of transmissionMetacercaria ingestionMetacercaria ingestionSkin penetration of cercariaSkin penetration of cercaria

Intermediate hostIntermediate host Harbors larval formHarbors larval form Have 2 intermedite host EXCEPT SchistosomaHave 2 intermedite host EXCEPT Schistosoma

First intermediate hostFirst intermediate hostALWAYS A SNAILALWAYS A SNAILinfective stage is miracidiuminfective stage is miracidium

Second intermediate hostSecond intermediate hostInfective stage: metacercariaInfective stage: metacercariaAquatic vegetation: FasciolaAquatic vegetation: FasciolaFresh water fish: ChlonorchisFresh water fish: ChlonorchisClams or crabs: ParagonimusClams or crabs: Paragonimus

Liver FlukesLiver Flukes1. Fasciola hepatica1. Fasciola hepatica

Sheep liver flukeSheep liver fluke

Habitat: liverHabitat: liver

Transmission: ingestion of contaminated Transmission: ingestion of contaminated aquatic vegetationaquatic vegetation

Manifestation: Manifestation: Abd. Colic, obstructive jaundice, cough, Abd. Colic, obstructive jaundice, cough,

vomitingvomiting

Diagnosis: Diagnosis: FecalysisFecalysisBachman intradermal testBachman intradermal testComplement fixation testComplement fixation test

Treatment:Treatment: Bithionol (drug of choice)Bithionol (drug of choice) Emetine hydrochlorideEmetine hydrochloride PraziquantelPraziquantel

Prevention:Prevention: MulluscicidesMulluscicides Sanitary protection of waterbedsSanitary protection of waterbeds

2. Chlonorchis sinensis (Opistorchis 2. Chlonorchis sinensis (Opistorchis sinensis) sinensis) Chinese liver flukeChinese liver flukeHabitat: liverHabitat: liverTransmission: ingestion of raw or Transmission: ingestion of raw or

uncooked freashwater fishuncooked freashwater fishManifestation:Manifestation:

mildmildProgressive: Irregular appetite, fullness of Progressive: Irregular appetite, fullness of

abdomen, diarrhea, edema, hepatomegalyabdomen, diarrhea, edema, hepatomegalySevere: cirrhosis, portal hypertensionSevere: cirrhosis, portal hypertension

Diagnosis: Diagnosis: FecalysisFecalysisDuodenal aspirationDuodenal aspiration

Treatment: chloroquine, praziquantelTreatment: chloroquine, praziquantel

Prevention: thorough cooking of fish, Prevention: thorough cooking of fish, sewage disposalsewage disposal

Intestinal FlukesIntestinal FlukesFasciolopsis buskiFasciolopsis buski

Giant intestinal flukeGiant intestinal flukeHabitat: duodenum and jejunumHabitat: duodenum and jejunumDisease: FasciolopsiasisDisease: FasciolopsiasisTransmission:Transmission:

Ingestion of contaminated aquatic Ingestion of contaminated aquatic vegetablesvegetables

ManifestationsManifestationsToxic iarrhea, ascites, edemaToxic iarrhea, ascites, edema

Diagnosis: Diagnosis: History and PEHistory and PEFecalysisFecalysis

Treatment: PraziquantelTreatment: Praziquantel

PreventionPreventionThorough washing of vegetablesThorough washing of vegetablesAvoid water chestnuts in infected watersAvoid water chestnuts in infected watersProhibit use of night soilProhibit use of night soil

Lung FlukeLung FlukeParagonimus westermaniParagonimus westermani

Oriental Lung FlukeOriental Lung Fluke

Habitat: lungHabitat: lung

Disease: ParagonimiasisDisease: Paragonimiasis

Transmission: eating freshwater crabsTransmission: eating freshwater crabs

Manifestations:Manifestations:Productive cough, occasionaly Productive cough, occasionaly

hemoptysishemoptysisChest pain, night sweats, abdominal Chest pain, night sweats, abdominal

pain, diarrhea, epilepsypain, diarrhea, epilepsy

Diagnosis: Diagnosis: Chest xrayChest xray Sputum examSputum exam FecalysisFecalysis Complement fixation testComplement fixation test

Treatment: PraziquantelTreatment: Praziquantel

Blood FlukesBlood FlukesSchistosomesSchistosomes

DioeciousDioecious

Always in copula, “romantic parasite”Always in copula, “romantic parasite”

Three speciesThree speciesSchistosoma japonicumSchistosoma japonicumSchistosoma hematobiumSchistosoma hematobiumSchistosoma mansoniSchistosoma mansoni

Schistosoma mansoniSchistosoma mansoniManson’s blood flukeManson’s blood flukeHabitat: Habitat:

inferior mesenteric plexusinferior mesenteric plexus

rectumrectumDisease: Disease:

BilharziasisBilharziasis

Intestinal schistosomiasisIntestinal schistosomiasis

Intermediate hostIntermediate hostSnail: Biomphalaria, AustralorbisSnail: Biomphalaria, AustralorbisEggs: non-operculated, with lateral Eggs: non-operculated, with lateral

spinespineCercaria has forked tailCercaria has forked tail

Diagnosis: fecalysis Diagnosis: fecalysis urine urine

Schistosoma hematobiumSchistosoma hematobiumVesicle blood flukeVesicle blood fluke

Habitat: vesical and pelvic plexus of Habitat: vesical and pelvic plexus of venous circulationvenous circulation

Disease: urinary bilharziasisDisease: urinary bilharziasis

Intermediate host: Intermediate host: Snail: Bulimus, Planorbarius, PhysopsisSnail: Bulimus, Planorbarius, PhysopsisEggs: non-operculated, with terminal Eggs: non-operculated, with terminal

spinespineCercaria: forked tailCercaria: forked tail

Diagnosis: urinalysis Diagnosis: urinalysis fecalysis fecalysis

Schistosoma japonicumSchistosoma japonicum

Oriental blood flukeOriental blood fluke

Habitat: Habitat: superior mesenteric veins of small superior mesenteric veins of small

intestineintestine

Disease: Oriental schistosomiasisDisease: Oriental schistosomiasis

Intermediate host:Intermediate host:Snail: Oncomelania quadrasiSnail: Oncomelania quadrasiEggs: with abbreviated spineEggs: with abbreviated spineCercaria: forked tailCercaria: forked tail

Diagnosis: fecalysis onlyDiagnosis: fecalysis only

Clinical Clinical manifestationsmanifestations

Dermatitis: Swimmer’s itchDermatitis: Swimmer’s itch

Diarrhea, splenomegaly, Diarrhea, splenomegaly, lymphadenopathylymphadenopathy

Hematuria, urethral obstructionHematuria, urethral obstruction

Headache, disorientation, amnesia, Headache, disorientation, amnesia, comacoma

Treatment: PraziquantelTreatment: Praziquantel

Prevention: Prevention: Proper waste disposal Proper waste disposal molluscidesmolluscides

Quiz TimeQuiz Time

Please get 1/8 paperPlease get 1/8 paper

1. Paragonimus westermani1. Paragonimus westermani

A. liver flukeA. liver fluke C. intestinal flukeC. intestinal fluke

B. lung flukeB. lung fluke D. blood flukeD. blood fluke

2. Definitive host of trematodes2. Definitive host of trematodes

A. pigsA. pigs C. cowC. cow

B. manB. man D. snailD. snail

3. Synonymous with Trematodes3. Synonymous with Trematodes

A. tapewormA. tapeworm C. hookwormC. hookworm

B. flukesB. flukes D. roundworm D. roundworm