Ifeanyi Jonas Ezema
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University of Nigeria Research Publications EMEJULU, Chinyelu Angela Author PG/M.Sc/90/9564 Epidemiology of Urinary Schistosomiasis in Title Agulu Lake Area of Anambra State, Nigeria Biological Sciences Faculty Zoology Department July, 1992 Date Signature EPIDEMIOLOGY OF URINARY SCH ISTOSOMIASIS IN AGULU LAKE AREA UF ANAMBRA STATE, NIGERIA EMEJULU, CHINYELU ANGELA PG/M.Sc./90/9564 A DISSERTATION SUBMITTED TO'THE UNIVERSITY OF NIGERIA NSUKKA, IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE AWARD OF MASTERS OF SCIENCE (M.Sc.) DEGREE IN ZOOLOGY (PARASITOLOGY) * SUPERVISOR: DR. F.C. OWOR JULY 1992 iii DEDICATION This thesis is dedicated with love to my little nephew Chidiebele Emejulu. ACKNOWLEDGEMENT MY greatest thanks and gratitude are directed to my upervisor, Dr. F.C. Okafor for his interest, encoiurage- ment, advice, constructive criticisms, providing neces- sary materials and for painstakingly reading through the entire manuscript and making useful suggestions. My immense gratitude also goes to Dr. J.C. Ezigbo and my brother-inlaw, Dr. C.E. Iloegbu for their encouragement and for making available to me laboratory materials and equipment used for the work. I am also grateful to my daddy's drivers, Isaac and Ikechukwu who helped in making things easier for me during collection of the snail and urine samples used for the work. I am equally indebted to Rev. Prof. E.U. Iheagwam and Dr. Ezenwaji both of Zoology Department, University of Nigeria, Nsukka for their various advice and interest in the progress of the work which spurred me to greater activity. I thank all the academic and non-academic staff of the Department of Zoology, University of Nigeria, Nsukka, for their various forms of assistance each rendered to me. Finally, I am highly indebted to my parents who without their financial and moral support, this work would not have been possible. EMEJULU, C.A. TABLE OF CONTENTS Page Title Page . i Certification . ii Dedication . -. iii Acknowledgement . iv Table of Contents . vi List of Figures . viii List of Plates . ix List of Tables . X Abstract . xii CHAPTER ONE: INTRODUCTION AND LITERATURE REVIEW . 1 Introduction .. 1 Distribution . 1 The Disease Schistosomiasis, thc Parasite and Life Cycle 2 Epidemiology and Socio-cul- tural ~s~ects . 5 Objectives of Study . 11 CHAPTER TWO: MATERIALS AND METHODS .. 13 2.1 The Study Area . 13 2.2 Human Ecology . 13 2.3 Study Techniques .. 25 2.3.1 Epidemiology . 25 i School . .. 25 ii) Community .. 26 iii) Collection of snails and Analysis . 28 vii 2.3.2 KAP .. .. .. CHAPTER THREE : RESULTS . .. .. 3.1 Epidemiology . i School . ii) Commmity . 3.2 Related Concurrent Studies i Visible Haematuria .. ii) Snail Study . .. iii) Distance and Domestic Water Supply . .. KAP . Characteristics of the Respondents . .. Knowledge of the Disease .. Local ~erminologiesfor Urinary Schistosomiasis . ii) Theory of Causation and Transmission . iii) 3.3.3 Attitude . 3.3.4 Practices .. .. CHAPTER FOUR: DISCUSSION .. CHAPTER FIVE: CONCLUSION . .. REFERENCES . APPENDICES .. viii LIST OF FIGURES Pigurc 1: The Lifc Cycle of -S. hzcmatohi.1.1rn-- and -S. rrmnsoni .. 4 Fiqurc 2: M7p of Anambra Statc showing the Local Govcrnmcnt Arcas . .. 14 Pigurc 3: Map of Awka Local Governmcnt Arca showing s tudics coirmuni tics . 15 Pigure 4: Map of Njikoka Local Governmcnt Area showing studiec! conmxnitics 1G Figure 5: Plap of Annocha Local Govcrnrncnt Area showing stud.icd cornr;lunities 17 Pigure 6: Agulu Lakc Rcgion showing vill-2gcs in NL~imd Ayulu with case of Urinary Schistoso~niasis . 18 Figure 7: Prevalences of S. --hacmatobium by Scx, Age and ~cEoolAIfliation .. 36 Figurc 8: Prevalenccs of --S. -----hq3cmatobium .-- by Sex, Age and Community Affiliation 41 Figure 9: Age Preval.cncc and Tntcnsity (egg output)- of Inf cc tion wiL!l -S . hnema tobium in the Enilemic ~ommunitics . 43 Figure 10: Occupationzl Variation among Schools infected with Urinary Schistosomiasis in the Endemic Communities . .. 46 Pigure 11: Prevalence Rate and Domestic Water Supply Distance . .. 54 LIST OF PLATES Plate 1: Ezunwani Stream at Awba-Ofcmili (Awka L,GA) showing human activities Plate 2: Aliulo Stream at Nawgu (Njikoka LGA) showing hulnan activities . Part of Ulasi Strcarn i.n Nri (Anaochn LGA) . Plate 4: Part of Agul-u Lake showing Vegetation .. Arm 1 of Agulu Lake (Agulu siclc) showing human activities . Plate 6: Arm 2 of Agulu Lake (Agulu sidc) Plate 7: Arm 5 of Agulu Lakc (Nri sidc) Platc 0: Shell of Blllinus (Physopsis) globosus . Plate 9: Shcll of Dulinus truncatus var pp rohlfsi. P . Furcocercous Cercaria of -S. haanntobium .. LIST OF TABLES Page Tablc Distrihution of Urinary Schistosomiasis in thc LGAs and Prevalcncc Ratc in Affcctcd Schools TCLlJlc Prevalence Rate of Infection by Scx in thc Affected Schools in Anaocha LGA . Tdble Prcvalcnce of Infcction and Gcomc- tric mcan of the cgg outpui (from those infcctcd in thc varjous Schools) by Agc .. Tablc Distribution of Urinary Scliistoso- miasis in thc LGAs and Pzcvalencc Ratc in thc Various Cornmnitics Table Prevalence Rate of Infection by Sex in t.hc Endcniic Corrmuni tics Table Prevalence of S. hacmatohium and Ccomctric mean-of the cg7 0u!tPut Table Geometric mean of egq Output per 10 ml urine from those Inicctcd by Sex, Age and Community . Table Prevalence of S. haematobiurn in Occupational ~rou~sin endemic Tablc Visible haematuria and Intensity of egg Output . Table Visible haematuria as a Diagnostic Test .. .. .. Table No. of Snails Collected, No. Infec- ted and Infection Rates in 1991 and 1992 . .. .. .. .. Tab1 e Prevalence Rate and Natural Domestic Water Distance .. Page Table 13: Community and Sex Specific Characteristics of Respondents .. 55 Table 14: Age and Sex Specific Characteris- tics of Respondents . .. 56 Table 15: Definition of -S. haematobiurn by Cornmuni ty . .. 57 Table 16: Responses on Symptoms of Urinary Schistosomiasis .. .. .. 58 xii ABSTRACT The presence of -S. haematobium infection was investigated in school children and in 16 communities in Anambra State, Nigeria. The disease was prevalent in 4 schools and found endemic in 3 communities. Out of the 200 pupils examined in the 4 schools, 104 (52.0%;o I were infected. Out of the 128 males involved in the school study, 76 (59.4%) were infected while out of the 72 females examined, 28 (38.9%) were infected. Interestignly however., the infection rates difference between males and females was not statistically significant at 5% level. In the community study, Nri and Agulu had similar prevalence rates (37.2% and 29.4%). Adazi-Nnukwu had a very low prevalence rate (6.0%). The overall geometric mean egg output in the cornrnunity study was 22.4/10m1 Urine. The number and levels of visible haematuria were measured in relation to' the presence and intensity of -S.haematobium - egg output in the urine of individuals in the endemic communities. It was found that 61 individuals passed reddish (bloody) urine while 164 individuals passed brown urine (tending towards red). Visible haematuria as a diagnostic test for the presence of the infection was statistically highly sensitive (97%) but showed low specificity (20.6%). There were variations in the xiii intensity of egg output within the same shade of haematuria of different individuals. There was also a lot of overlap in egg output between the different shades. However there was a noticeable increase in egg output as the colour of urine deepened into frank red. Malacological surveys show that snail distribution is focal especially at human water contnct sites at arms of the lake and a stream (Ulasi) in Nri. A study to examine the effect of distance of rural water supply on prevalence showed that households tend to use water from nearest sources. The prevalence rate showed a significant decrease (P=0.05) with increasing household distance to natural water source (c.g. 71.4% at < 250m and 22.2% prevalence at> 2,000m). The knowledge, Attitudes and Practices (KAP) of people in relation to the disease in the endcmic communities was carried out. Of the 200 respondcnts, 67 (22.3%) were previously infected while 233 (77.7%) were never infected. All the respondents associated the disease with passing of blood in urine. Oya obalz (disease with blood), Mgbu obala (pain with blood), Mamiri obala (urine with blood) are various terminologies for the disease in these communities. The presence of the disease was linked with the Nigerian-Biafran civil war of 1967-1970. Although majority 98.3% of the xiv respondents did not believe it is a killing disease, 73.7% believed that it is a serious disease. A good number 129 (438) prefer&oing to hospital for treatment. CHAPTER ONE INTRODUCTION AND LITERATURE REV1 EW INTRODUCTION Schistosomiasis is widespread with a relatively low mortality rate but accompanied by a high mobidity rate - causing severe debilitating illness in millions of people. The disease afflicts over 271 million people in the world, 168 million of them in Africa (Peters, 1978). Estimated mortality rate is less than 200,000 per year and the number of people considered a risk is 500 - 600 million while number of countries affected is 76 (WHO 1990). It is often associated with water development projects, such as dams and irrigation schemes, where the snail intermediate hosts of the parasite breed in water where people swim, wash and fish. The disease is essentially one of rural communities, where there exists ignorance, poverty, poor personal and community hygiene and poor sewage disposal systems. DISTRIBUTION Each of the established species of Schistosoma infecting man has a specific geographic distribution. Both S. mansoni and -S. haematobium are wide-spread in Africa. S. haematobium alone occurs in Tunisia, Algeria, Niger, Morocco, Guinea-Bissau, Mauritania, Congo Republic (Brazzaville), Somalia and the Island of Mauritus. Only -S. mansoni occurs in the endemic areas of the New World, Brazil has the largest number of cases (Wilson, 19'75; WHO, 1980) estimated at 8 million cases.