1) The document summarizes key information about medically important trematodes found in the Philippines, including their life cycles, intermediate and definitive hosts, diagnostic stages, and symptoms caused in humans. 2) It provides a table outlining 14 trematode species, their first and second intermediate hosts, definitive host, and diagnostic stage. A second table provides details on the ova, adult worms, pathogenesis, and drug of choice for each species. 3) The document concludes with a table comparing characteristics of the three major Schistosoma species affecting humans such as testes morphology, ovary features, intestine length, egg properties, intermediate host, and definitive host.

1. Notes on Philippine Medically Important Trematodes
Meccar Moniem Elino, BSBio IV , Davao Doctors College
Instructor: Mrs. Chalee Sienes-Reyes, RMT, MSMT, Ph.D
Reference: Philippine textbook of Medical Parasitology 2nd ed.(2004) UP. Edited by
Vicente Y. Belizario, Jr. and Winifreda U. de Leon
Definitive Diagnostic
Common Name 1st IH 2nd IH
Host Stage
Segmentina and T. bicornis, N. lotus, Humans
Fasciolopsis buski Giant Intestinal Fluke snail Plant Egg in stool
Hippeutis E. tuberculosa and Pigs
Echinostoma ilocanum Garrison's Fluke G. Pila luzonica,
Eggs in
snail convexiusculus, Snail Lymnea Humans
stool
H. umbilicalis cummingiana
Artyfechinostomum malayanum
Heterophyes heterophyes Minute Fish Fluke C. chanos (Bangus),
Haplorchis taichui Melania juncea, C.bethiacus (Hito), Eggs in
snail Thiara riquetti Fishes O. striatus (dalag), S. Human Sputum
Metagonimus yokogawai Intestinal Fish Fluke (Brackish) canalicatus(danggit), and Stool
Haplorchis yokogawai T. nilotica (tilapia)
Temperate/SheepLiver Ipomea obscura Human,
Fasciola hepatica Lymnea
Fluke (Kang Kong), cow, Eggs in
snail philippinen-sis, Plants
Nastorium officinale cattle, stool
Fasciola gigantica Tropical/Giant liver Fluke Lymnea swinhoei
(Water Cress) sheep
Parafossarulus,
Bulimus,
Clonorchis sinensis Chinese Liver Fluke snail Semiculcoapira, Fish Fish of Family Humans
Alocinma, Cyprinidae (Tilapia and Fish Eggs in
Melanoides nilotica) St. Peter's eating stool
Fish mammals
Opisthorcis felineus Cat Liver Fluke
snail Bithynia Fish
Opisthorcis viverrini Sea Liver Fluke
Eggs in
Ante-melania Sundathelphusa
Paragonimus westermani Oriental / Lung Fluke snail crabs Human sputum
dactylus/asperata philippina
and stool
Macro-chlamys Technomyrmex
Eurytrema pancreaticum Pancreatic Fluke snail Ant Human
indica deterquens (ant)
Human
O. hupensis and eggs in
Schistosoma japonicum Oriental Blood Fluke snail X X
quadrasi Domestic stool
Animals
Biomphalaria and eggs in
Schistosoma mansoni Manson's Blood Fluke snail X X Human
Australorbis stool
eggs in
Schistosoma haematobium Visceral Blood Fluke snail Bulimus X X Human urine
specimen

2. Ova Adult Pathogenesis Drug of Choice
Adult Reddish gray
Horse-shape collar of spines (circum oral disk)
around the oral suckers
Echinostoma ilocanum
Straw-colored 49-51 collar spines
Integument is covered by plaque like scales Echinostomiasis, general
Operculated
Simple intestinal caeca intoxication, diarrhea,
Ovoid Praziquantel
Ulceration to the
Similar to Fasciola and
attachment site
Fasciolopsis buski ova
with 43 to 45 collar spines, testes are large
with six to nine lobes in tandem. The ovary is
A. malayanum
small rounded oval anterior to the testes and
pre equatorial
Heterophyes heterophyes minute operculate
intestine start from midpart
Haplorchis taichui ovoidal and light
elongated, pyriform & grayish 1-1.7 x .3x.4mm
Metagonimus yokogawai brown Dyspnea, Rusty/Bloody
cuticle covered with scale like spines Small
28-30 x 15-17 micra Sputum, Space Occupying
Oral suckerwith thick wall and muscular
slight shoulder @ the Lesions, Colicky Praziquantel
Genital sucker @ left posterior border with 2
rim of operculum Abdominal Pain and
Haplorchis yokogawai ovoid testis post of 5th body subglobose ovary
& no abopercular Diarrhea
anterior of testis vitellaria with large
proturberance
polygonal follicles in lateral posterior end
Mature when laid
Immature operculated
Large, broadly Ovate and Narrow at posterior
Yellowish brown Fasciolopsiasis, Intestinal
end
ellipsoidal Obstruction, Marked
Fasciolopsis buski no cephalic cone Praziquantel
130-140 x 80-85 micra, Eosinophilia, colic
2-7.5 x .8 - 2cm
clear thick shell and Diarrhea and vomiting
ALimentary tract simple and do not branch
operculated
(immature) Longer cephalic zone with conical projection
Fasciola hepatica
operculated stool Highly Branched (dendritic) intestine
140-150 x 65-90 micra
(hepatica)
160-190 x 70-90 micra Biliary colic, Jaundice,
(gigantica) Abdominal Pain, Mark
Bithionol,
Light yellow Biled Eosinophilia, Biliary Tract
Fasciola gigantica
strained obstruction
Shorter cephalic Zone with conical projection
Transparent with thin
Highly Branched (dendritic) intestine
double walls
Contain lecithin
granules (immature)
Egg operculated
mature electric bulb simple or unbranched intestine
shape bigger oral sucker than O. felineus Cholangitis, biliary
Clonorchis sinensis Posterior has small 2 highly branched denritic testes post cirrhosis, obstructive
knob vitellaria: mid 3rd of the intestine jaundice, malignant Praziquantel
tea pot lid - shape of yolk gland 10-25 x 2-3mm changes of the liver and
operculum; Eggs
pancreas
passed out via the
Opisthorcis felineus common bile duct into Lobate highly branched testes; vitellaria: mid
Opisthorcis viverrini the liver 3rd
Yellowish, Thick
Paragonimiasis, Cough,
shelled, operculated Body covered with spines Coffee Bean Shape,
Paragonimus westermani hemoptysis, Praziquantel
with thickened Found in Pairs or in threes in Fibrotic capsules
Misdiagnosed as PTB
abopercular egg
Operculated
Thick shelled Pancreatic fluke
Eurytrema pancreaticum Dark brown in color Stout worm with ruffled margins Pancreatitis Praziquantel
Embryonated when oral sucker is larger than the ventral sucker
laid
Diagnostic Test
Schistosoma japonicum Schistomiasis, Cercarial
Schistosoma mansoni (Next Table) Kato katz,
Dermatitis, Hepatosplenic
Immunodiagnostic
Disease (Granulomatous
Schistosoma haematobium Test
Reaction)

3. Major Differences Among Schistosoma spp.
Feature S. japonicum S. mansoni S. haematobium
Testes (male) 6-7 in a single file 8 -9 in a zigzag row 4 -5 in groups
Ovary (Female) In the middle of the body; contains 50 or more Anterior to the middle of the body; Behind the middle of the body; contains
eggs contains 1-3 eggs 20 – 30 eggs
Intestine short longest long
Egg Lateral knob Lateral spine Terminal spine
Intermediate Host Oncomelania Biomphalaria and Australorbis Bulimus (Physopsis)
Definitive Host Man and domestic animals Man Man