TREMATODE INFECTIONS AND DISEASES OF MAN AND ANIMALS TREMATODE INFECTIONS AND DISEASES OF MAN AND ANIMALS

By

V. Kumar Institute of Tropical Medicine, Antwerp, Belgium

SPRINGER-SCIENCE+BUSINESS MEDIA, B.V. A C.I.P. Catalogue record for this book is available from the Library of Congress.

ISBN 978-90-481-5152-3 ISBN 978-94-017-3594-0 (eBook) DOI 10.1007/978-94-017-3594-0

Printed on acid-free paper

Cover photomicrograph: Cross section of pulmonary lesions due to Paragonimus westermani in man.

All Rights Reserved © 1999 Springer Science+Business Media Dordrecht Originally published by Kluwer Academic Publishers in 1999 No part of the material protected by this copyright notice may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording or by any information storage and retrieval system, without written permission from the copyright owner. To Suman and our Smita, Ashish and Kavita CONTENTS

Page Preface ...... 13 Acknowledgements ...... 17

Chapter 1 Introduction ...... 19 1.1 The digenetic trematodes ...... 19 1.2 Morphological forms of the adult digenetic trematodes ...... 19 1.3 Predilection sites in the definitive hosts ...... 21 1.4 Tegument;- the host-parasite interface ...... 22 1.5 Propagation patterns of the digenetic trematodes ...... 24 1.6 Morphological forms of the cercariae of digenetic trematodes ...... 27 1.7 Principles of control measures against trematode infections ...... 30 1. 7.1 Chemotherapeutic measures ...... ". . . 32 1.7.2 Mollusc control measures ...... 34 1.7.3 Infection evasive measures ...... 37 1.8 Chemotherapeutic agents against trematode infections ...... 39 1.8.1 Drugs against schistosomiasis ...... 40 1.8.2 Drugs against fascioliasis ...... 44 1.8.3 Drugs against dicrocoeliasis ...... 45 1.8.4 Praziquantel;- a wide-spectrum drug against zoonotic trematode infections ...... 46 1.9 Further reading ...... 4 7

Chapter 2 Schistosomiasis ...... 50 2.1 Causative parasites ...... 50 2.2 Morphological features ...... 51 2.3 Schistosomiasis in the African, Middle Eastern, South European, South American and Caribbean countries ...... 58 2.3.1 S. mansoni schistosomiasis ...... 58 2.3.2 S. haematobium schistosomiasis ...... 63 2.3.3 S. intercalatum schistosomiasis ...... 69 2.3.4 S. bovis schistosomiasis ...... 70 2.3.5 S. mattheei schistosomiasis ...... 72 2.3.6 S. curassoni schistosomiasis ...... '...... 74 2.3.7 S. margrebowiei schistosomiasis ...... 78 2.3.8 S. /eiperi schistosomiasis ...... 79 2.3.9 S. rodhaini schistosomiasis ...... 79 2.4 Schistosomiasis in the Asian countries ...... 80 2.4.1 S. japonicum schistosomiasis ...... 80 8

2.4.2 S. mekongi schistosomiasis ...... 84 2.4.3 S. indicum schistosomiasis ...... 85 2.4.4 S. spindale schistosomiasis ...... 86 2.4.5 S. nasale schistosomiasis ...... 88 2.4.6 S. incognitum schistosomiasis ...... 89 2.4.7 0. turkestanicum schistosomiasis ...... 90 2.4.8 0. dattai schistosomiasis ...... 92 2.4.9 0. harinasutai schistosomiasis ...... 93 2.5 Features of life cycle ...... 93 2.6 Pathogenesis and immunopathology ...... 98 2. 7 Immunity ...... 103 2.8 Vaccination studies ...... 106 2.9 Diagnosis ...... 1 08 2.1 0 Chemotherapy ...... 116 2.11 Schistosomiasis as a human health problem ...... 119 2.12 Cercaria! dermatitis ...... 122 2.13 Further reading ...... 124

Chapter 3 Paragonimiasis ...... 132 3.1 Causative parasites ...... 132 3.2 Paragonimiasis in the Asian countries ...... 133 3.2.1 P. westermani paragonimiasis ...... 133 3.2.1.1 Features of life cycle ...... 138 3.2.1.2 Mode of infection ...... 140 3.2.1.3 Pathogenesis ...... 141 3.2.1.4 Pathology and pathogenicity ...... 142 3.2.2 P. miyazakii paragonimiasis ...... 146 3.2.3 P. skrjabini paragonimiasis ...... 148 3.2.4 P. heterotremus paragonimiasis ...... 148 3.2.5 P. phi/ippinensis paragonimiasis ...... 149 3.3 Paragonimiasis in the Americas ...... 150 3.3.1 P. mexicanus paragonimiasis ...... 150 3.3.2 P. kellicotti paragonimiasis ...... 152 3.4 Paragonimiasis in the African countries ...... 155 3.4.1 P. uterobilateralis paragonimiasis ...... 155 3.4.2 P. africanus paragonimiasis ...... 155 3.5 Natural definitive hosts of Paragonimus spp...... 158 3.6 Diagnosis ...... 159 3.7 Chemotherapy...... 162 3.8 Further reading ...... 163

Chapter 4 Fascioliasis and fasciolopsiasis ...... 168 4.1 Causative parasites ...... 168 4.2 Fascioliasis ...... 169 4.2.1 F. hepatica fascioliasis ...... 169 4.2.2 F. gigantica fascioliasis ...... 171 4.2.3 Features of life cycle ...... 174 9

4.2.4 Pathogenesis and pathology ...... 177 4.2.5 Pathophysiology and pathogenicity of fascioliasis in ruminants . . 183 4.2.6 Immunity ...... 186 4.2.7 Human fascioliasis ...... 189 4.2.8 Economic impact of fascioliasis in ruminants ...... 193 4.2.9 Diagnosis ...... 196 4.2.1 0 Chemotherapy ...... 200 4.3 Fasciolopsiasis 203 4.3.1 F. buski fasciolopsiasis ...... 203 4.3.2 Features of life cycle ...... 205 4.3.3 Pathogenicity ...... 207 4.3.4 Diagnosis and chemotherapy ...... 207 4.4 Further reading ...... 208

Chapter 5 Dicrocoeliasis and eurytremiasis ...... 215 5.1 Causative parasites ...... 215 5.2 Dicrocoeliasis ...... 216 5.2.1 D. dendriticum dicrocoeliasis ...... 216 5.2.1.1 Features of life cycle ...... 219 5.2.2 D. hospes dicrocoeliasis ...... 221 5.2.2.1 Features of life cycle ...... 223 5.2.3 Pathogenesis and pathology ...... 223 5.2.4 Pathogenicity ...... 226 5.2.5 Diagnosis ...... 227 5.2.6 Chemotherapy ...... 227 5.2.7 Dicrocoeliasis in man ...... 228 5.3 Eurytremiasis ...... 229 5.3.1 E. pancreaticum eurytremiasis ...... 229 5.3.2 E. coelomaticum eurytremiasis ...... 230 5.3.3 Features of life cycle ...... 232 5.3.4 Pathogenicity and pathology ...... 233 5.3.5 Diagnosis and chemotherapy ...... 235 5.3.6 Eurytremiasis in man ...... 236 5.4 Further reading ...... 236

Chapter 6 Clonorchiasis and opisthorchiasis ...... 241 6.1 Causative parasites ...... 241 6.2 Clonorchiasis ...... 242 6.2.1 C. sinensis clonorchiasis ...... 242 6.2.1.1 Features of life cycle ...... 246 6.2.1.2 Mode and sources of infection ...... 248 6.2.1.3 Pathogenesis and pathology ...... 249 6.2.1.4 Pathogenicity ...... 252 6.2.1.5 Diagnosis ...... 254 6.2.1.6 Chemotherapy ...... 257 6.3 Opisthorchiasis ...... 258 6.3.1 0. felineus opisthorchiasis ...... 258 10

6.3.2 0. viverrini opisthorchiasis ...... 261 6.~.3 Pathology and pathogenicity ...... 264 6.3.4 Diagnosis and chemotherapy ...... 267 6.4 Opisthorchiids as indigenously occurring infections of man and animals in the Americas ...... 268 6.5 Further reading ...... 270

Chapter 7 Paramphistomiasis ...... 275 7.1 Causative parasites ...... 275 7.2 Family : Paramphistomidae ...... 276 7.2.1 Paramphistomum cervi ...... 277 7.2.2 Explanatum explanatum ...... 279 7.2.3 Cotylophoron cotylophorum ...... 281 7.2.4 Ca/icophoron calicophorum ...... 282 7.2.5 Orthocoe/ium scoliocoe/ium ...... 284 7.2.6 Pseudodiscus collinsi ...... 286 7.2.7 Gastrodiscoides hominis ...... 288 7.2.8 Gastrodiscus aegyptiacus ...... 289 7.2.9 Homalogaster pa/oniae ...... 291 7 .2.1 0 0/veria indica ...... 293 7.3 Family : Gastrothylacidae ...... 295 7 .3.1 Gastrothylax crumenifer ...... 296 7.3.2 Carmyerius spatiosus ...... 297 7.3.3 Fischoederius cobbo/di ...... 298 7.4 Features of life cycle ...... 300 7.5 Development in the definitive hosts ...... 303 7.6 Acute paramphistomiasis in ruminants ...... 304 7 .6.1 Pathogenesis ...... 305 7.6.2 Pathology ...... 307 7.6.3 Clinical effects ...... 310 7.7 Infections by mature paramphistomes ...... 312 7.8 Diagnosis ...... 313 7.9 Chemotherapy...... 314 7.10 Further reading ...... 317

Chapter 8 Echinostomiasis, heterophyiasis, metagonimiasis and other intestinal trematode infections ...... 322 8.1 Echinostomiasis ...... 323 8.1.1 E. ilocanum echinostomiasis ...... 324 8.1.2 E. malayanum echinostomiasis ...... 325 8.1.3 Other echinostome infections ...... 328 8.1.4 Pathogenicity ...... 331 8.1.5 Diagnosis and chemotherapy ...... 332 8.2 Heterophyiasis and metagonimiasis ...... 333 8.2.1 H. heterophyes heterophyiasis ...... 334 8.2.1.1 Pathogenicity ...... 335 11

8.2.2 M. yokogawai metagonimiasis ...... 337 8.2.2.1 Pathogenicity ...... 339 8.2.3 Diagnosis and chemotherapy ...... 342 8.3 Other minute intestinal flukes infecting man ...... 343 8.3.1 Lecithodendriid infections ...... 343 8.3.2 Plagiorchiid infections ...... 344 8.3.3 Microphallid infection ...... 344 8.3.4 Diagnosis and chemotherapy ...... 345 8.4 Nanophyetid infections ...... 345 8.5 Gymnophallid infection ...... 347 8.6 Diplostomid infections ...... 347 8.7 Intestinal flukes of the ruminant hosts ...... 349 8.8 Further reading ...... 350

Subject index ...... 354 PREFACE

The form of presentation of this book deviates somewhat in that the statements are not supported by citation of authorities as sources of information. However, succeeding each chapter, a list of references is supplied as materials for further in depth consultation. For the sake of brevity and to cope with the enormity of published materials, this list generally includes reviews or more recently published articles rather than the original work; my apologies to the primary authors of the classical studies.

This book is essentially a compilation of an up-to-date account on trematode infections and diseases of man and their domesticated animals. The author has in the process endeavoured to make a synthesis of the available knowledge on various aspects in this field of study. The introductory chapter is devoted mainly to the modern concepts of disease control strategies at community level as well as an up-date on the developments in antitrematodal drugs. For convenience, seven major disease groups, namely, schistosomiasis, paragonimiasis, fascioliasis and fasciolopsiasis, dicrocoeliasis and eurytremiasis, clonorchiasis and opisthorchiasis, paramphistomiasis, and diseases due to intestinal trematode infections are dealt with under separate chapters. Even this day, these diseases rank as a major cause of morbidity and mortality, both in man and their livestock. The causative agents of the diseases are illustrated as in toto mounted specimens and the current global perspectives on their distribution and prevalence are supplied. Pathology of the organs associated with these diseases are illustrated through photomicrographs and described and the pathogenicity and morbid effects of the diseases are discussed in the light of current developments. Newer technologies available for the diagnosis of these diseases are discussed and modern treatment and control methods outlined. 14

This treatise is intended as a text-book and, to some extent, as a reference material for the research workers, post-graduate students and those medical practitioners, veterinarians and other professionals concerned with the control of trematode diseases of man and animals. Barring a few exceptions, a majority of the trematode infections are also zoonoses; some are major and the others potential. Therefore, simultaneous treatment of the related medical and veterinary disease and zoonotic aspects is mutually complementary and appears rewarding. Also, the medical and veterinary methods of controlling these zoonotic infections can't be compartmentalized but instead constitute components of an integrated approach. Most of these zoonoses are food-borne and others water-borne.

The trematode infections and diseases are "one of humanity's most widespread and hidden scourges", as has been recently cautioned by Dr. Ken Matt, an expert on human trematodiasis with the World Health Organization. The association between a malignancy of human bile duct, cholangiocarcinoma, and opisthorchiasis due to Opisthorchis viverrini on the one hand and between an urinary bladder cancer, squamous cell carcinoma, and schistosomiasis due to Schistosoma haematobium on the other, has been documented for quite some time. These infections are generally believed to be the promoters, rather than initiators, of the malignancies. The International Agency for Research on Cancer have included these two disease producing agents as the biological carcinogenic risk agents to man. Human schistosomiasis in the African continent, due to S. haematobium or S. mansoni, shows an extremely focal and erratic pattern of distribution and newer foci of infections are being discovered. However, the factors which predicate the focal distribution of these two schistosomes are not fully understood. The radiographic images and clinical effects of pulmonary paragonimiasis in humans have been bemuddled with those of pulmonary tuberculosis in certain Asian and Latin American countries and newer areas of occurrence of paragonimiasis have been recorded in the recent years. With the fall of iron curtain and free outflow of scientific information from the former Union of Soviet Socialist Republics, the real magnitude of human opisthorchiasis due to 0. felineus in western Siberia has also come to the limelight; some 1.6 million persons are estimated affected with this disease in this region alone. Fascioliasis is a disease primarily affecting the ruminant stock. However, recently this disease in humans has emerged 15

as a menace of considerable concern and newer data have become available from a few Latin American countries. Current estimates suggest that, on a global basis, in excess of 2.3 million persons are infected with fascioliasis; mainly by eating contaminated watercress.

A rapid expansion of world tourism and migration of people from the developing countries to distant continents have altered the epidemiological pattern of the associated trematode-induced diseases to the extent that these maladies have become a concern for all the clinicians and pathologists. Also, an influx in international trade of food-items, particularly of the crustaceans, fishes, etc., which may be contaminated with the infective stages of the trematodes, from the disease endemic countries to distant continents may constitute a potential health hazard for the population living in the "sanitised" world. Although the medical and veterinary curricula generally include teaching of these trematode infections, the strategies for controlling these infections are not fully emphasised.

The trematode infections and diseases of man and animals are rampant in many developing third world countries and in some regions are a menace of considerable magnitude. The problem is compounded with the fact that the financial constraints in these countries limit the accessibility to much of the published information on the related disease topics. In this era of rapid technological transition, the developing countries are perhaps groping for an appropriate place in a scenario where the world has become more interdependent but, at the same time, the gap between the technology developers and its users has widened, more so now than ever before.

The commonly accepted acronyms, CT scan (computerized tomographic scan), DNA (deoxyribonucleic acid), Epg (Faecal egg density expressed as eggs per gram), ES antigens (excretory-secretory antigens), lg (immunoglobulin), IL (interleukin}, kDa (kilo-Dalton), rRNA (ribosomal ribonucleic acid}, SDS-PAGE (sodium dodecyl sulphate• polyacrylamide gel electrophoresis), etc. are used as such throughout the text. The following symbols are used for labelling the figures of worm specimens stained with carmine; a : acetabulum, ao : adhesive organ, c : caecum, cr : cirrus, cs : cirrus sac, 16 gc : gynaecophoric canal, gp : genital pore, od : oviduct, oe : oesophagus, oo : ootype, os : oral sucker, ov : ovary, p : pharynx, sr : seminal receptacle, sv : seminal vesicle, t : testes, u : uterus, vd : vitelline duct, vg : vitelline glands, vs : ventral sucker.

The terminology followed to designate diseases caused by trematode infections is adapted from a World Health Organization publication, International Statistical Classification of Diseases and Related Health Problems, 1994, volume 3, 1Oth edition; and this without prejudice to other terminology system.

Vinai Kumar ACKNOWLEDGEMENTS

The author is grateful to numerous colleagues and friends for their generous help and support in various ways and for the supply of materials used as illustrations in the text. I am particularly indebted to Prof. Bruno Gryseels, Prof. Stanny Geerts, Prof. emeritus Paul Gigase, Prof. Jef Brandt, Prof. Fans Van Gompel, Prof. emeritus Jos Mortelmans, Mr.Gilbert Roelants, Mr. Jos Van Hees and Mrs. Rolande Mies, Institute of Tropical Medicine, Antwerp, Belgium; Prof. Andre M. Deelder, University of Leiden, The Netherlands; Prof. Eric Van Marek, Faculty of Medicine, University of Antwerp, Belgium; Dr. Niels 0. Christensen, Danish Bilharziasis Laboratory, Charlottenlund, Denmark; Dr. Claus Meier-Brook, Institute of Tropical Medicine, Tubingen, Germany; Dr. Louis Maes, Mr. Oscar Vanparijs, Mr. Jan Fransen, Mr. Guy Jacobs, Mr. Lambert Leijssen and Mr. Hans Henderickx, Janssen Pharmaceutica, Beerse, Belgium; Dr. Jitender P. Dubey, Zoonotic Diseases Laboratory, U.S.D.A., Beltsville, U.S.A.; Prof. Han-Jong Rim, College of Medicine, Korea University, Seoul; Prof. Jong-Yil Chai, College of Medicine, Seoul National University, Seoul; Dr. Banchob Sripa, Faculty of Medicine, Khan Kaen University, Thailand; Dr. V.R. Southgate, The Natural History Museum, London and Prof. Kurt Pfister, Labor Pfister, Bern, Switzerland. Many materials used as illustrations originate from author's own collection. To numerous authors and publishers, I feel deeply obliged for their permission to use their published materials as illustrations which are of course acknowledged at the appropriate places in the text.

Publication of this book has been sponsored by the Director, Institute of Tropical Medicine, Antwerp, Belgium and received financial support of the National Bank of Belgium and the Janssen Pharmaceutica, Beerse, Belgium. The author would like to express his sincere appreciation for the courtesies.