Sanitary Parasitology
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:+2(0&(+( ,QWHJUDWHG*XLGH7R 6DQLWDU\3DUDVLWRORJ\ :RUOG+HDOWK2UJDQL]DWLRQ 5HJLRQDO2I¿FHIRUWKH(DVWHUQ0HGLWHUUDQHDQ 5HJLRQDO&HQWUHIRU(QYLURQPHQWDO+HDOWK$FWLYLWLHV $PPDQ±-RUGDQ WHO-EM/CEH/121/E INTEGRATED GUIDE TO SANITARY PARASITOLOGY World Health Organization Regional Office for the Eastern Mediterranean Regional Centre for Environmental Health Activities Amman – Jordan 2004 WHO Library Cataloguing in Publication Data WHO Regional Centre for Environmental Health Activities Integrated Guide to Sanitary Parasitology / WHO Regional Centre for Environmental Health Activities. p. 119 1. Sanitary parasitology – guidelines 2. Environmental health 3. Parasitic helminth 4. Water microbiology I. Title (ISBN 92-9021-386-8) [NLM Classification WA 671] © World Health Organization 2004 All rights reserved. The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the World Health Organization concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted lines on maps represent approximate border lines for which there may not yet be full agreement. The mention of specific companies or of certain manufacturers’ products does not imply that they are endorsed or recommended by the World Health Organization in preference to others of a similar nature that are not mentioned. Errors and omissions excepted, the names of proprietary products are distinguished by initial capital letters. The World Health Organization does not warrant that the information contained in this publication is complete and correct and shall not be liable for any damages incurred as a result of its use. Publications of the World Health Organization can be obtained from Distribution and Sales, World Health Organization, Regional Office for the Eastern Mediterranean, PO Box 7608, Nasr City, Cairo 11371, Egypt (tel: +202 670 2535, fax: +202 670 2492; email: [email protected]). Requests for permission to reproduce WHO EMRO publications, in part or in whole, or to translate them – whether for sale or for noncommercial distribution – should be addressed to the Regional Adviser, Health and Biomedical Information, at the above address (fax: +202 276 5400; email [email protected]). ii ACKNOWLEDGEMENTS This document is prepared and printed as part of the project entitled; "Improvement of Wastewater Management in some Arab Countries ", that is financed by the "Arab Fund for Economic and Social Development" (AFESD) in Kuwait. The World Health Organization wishes to express its appreciation to all those whose efforts made possible the production of this scientific document. Author: Dr Muna Y. Hindiyeh, Head of Environmental Science Department, Jordan University of Science and Technology. Scientific review and co-author of parts 9 and 10: Dr Saqer Al-Salem, Regional Centre for Environmental Health Activities (CEHA). Review and production: Eng. Mazen Malkawi, Regional Centre for Environmental Health Activities. Eng. Ahmed Kofahi, Jordan Environment Society. Mrs. Reham Al-Yaman, Regional Centre for Environmental Health Activities. Microscopic photography plates: Dr Ahmad Shugen, The Islamic Hospital, Jordan. Peer reviewers: Mr. Ihab Al Rajabi, Royal Scientific Society, Amman, Jordan. Dr Sami Abdel-Hafez, Dean of Research and Graduate Studies, Yarmouk University, Jordan. Prof Abubakr Ibrahim Ahmed, Professor of Parasitology and Director, School of Medical and Technological Sciences, University of Alneelain, Sudan. Dr Abdelhamid Gharbi, Chef de Service, Laboratoire Regional de Sante Publique,Direction Regional de Nabeul, Nabeul, Tunisia. Dr Lorenzo Savioli, Coordinator of Parasitic Diseases and Vector Control Unit,World Health Organization, Geneva. iii CONTENTS Acknowledgments iii Abbreviations Used in the Text vi Chapter 1 Sanitary Parasitology 1.1 Introduction 1 1.2 Worms Classification of Medical Importance and its Relation to Sanitation 2 1.3 Identification and Characteristics of Helminth Eggs 7 1.4 Life Cycles 20 Chapter 2 Factors Influencing the Fate of Helminth Eggs 25 2.1 Physical Factors Affecting Helminth Egg Survival 25 2.2 Chemical Factor Effecting Helminth Egg Survival 34 2.3 Biological Factors Affecting Helminth Eggs Survival 36 Chapter 3 Occurrence and Removal of Helminth Eggs from Raw Wastewater 37 and Sludge 3.1 Occurrence and Survival of Helminth Eggs in Raw Wastewater 37 3.2 Elimination of Helminths by Wastewater Treatment Plants 38 3.3 Occurrence and Survival of Helminth Eggs in Sludge 44 Chapter 4 Helminth Eggs as Indicator in Wastewater and Sludge 49 Chapter 5 Microbiological Quality Guidelines for Wastewater and Sludge 51 Application in Agriculture 5.1 Guidelines for Treated Wastewater Reuse in Crop Irrigation 51 5.2 Guidelines for Treated Wastewater Reuse in Fishpond Fertilization 53 5.3 Regulatiions and Guidelines for Sludge Utilization in Agriculture 53 Chapter 6 Laboratory Skills 55 6.1 Microscope Calibration 55 6.2 Use of Centrifuge 56 Chapter 7 Methods for Detection and Enumeration of Helminth Eggs in 57 Wastewater and Sludge 7.1 Introduction 57 7.2 Quantitative Determination of Helminth Eggs in Wastewater 60 iv Chapter 8 Determination of Helminth Eggs Viability 65 8.1 Introduction 65 8.2 Basic Vital Stains as a Presumptive Method for Determining Ascaris Eggs 68 Viability 8.3 Use of N-Butanol for Determination of Ascaris Eggs Viability 69 8.4 Method for the Enumeration and Viability Determination of Helminth Eggs in 69 Sewage Sludge 8.5 Analytical Methods for Viable Helminth Ova in Sludge 70 Chapter 9 Monitoring and Surveillance of the Reclaimed Wastewater and 75 Sludge for Agriculture Use 9.1 Introduction 75 9.2 Pollutants and Guidelines 75 9.3 Monitoring and Surveillance Guidelines 77 9.4 Monitoring Programs 81 9.5 Surveillance and Reporting Requirements 81 9.6 Analytical Methods 87 9.7 Other Considerations in Establishing Monitoring Requirements 87 9.8 Municipal Sludge Monitoring 88 9.9 Reporting and Record Keeping Requirements 89 Chapter 10 Health Aspects for Use of Reclaimed Wastewater in Agriculture and 91 Aquaculture 10.1 Introduction 91 10.2 Health Aspects 91 10.3 Epidemiological Evidence 93 10.4 Guidelines for Reuse of Wastewater in Agriculture and Aquaculture 93 10.5 Measures to Reduce the Health Hazards of Wastewater Reuse 100 10.6 Integration of the Various Measures for Health Protection 101 10.7 Special Health Issues 104 Glossary 105 Appendix I: Basic Epidemiological Features of Excreted Pathogens by 109 Environmental Category Appendix II: Preparation of Working Solutions of Vital Stains 111 Appendix III: Van Veer Grap Sampler 111 Appendix IV: Recommended Guidance for treated Wastewater Use in 112 agriculture References 113 v ABBREVIATIONS USED IN THE TEXT BOD Biological Oxygen Demand cap capita CFU Colony Forming Unit COD Chemical Oxygen Demand º C Degree Celsius d day DO Dissolved Oxygen EPA Environmental Protection Agency g gram h hour ha hectare HRT Hydraulic Retention Time kg kilogram l liter log logarithm m meter max. maximum mg milligram min minute min. minimum mm millimeter MPN Most Probable Number mV millivolte n Number PFRP Processes that Further Reduce Pathogens PSRP Processes that Significantly Reduce Pathogens RH Relative Humidity s second spp. species t time TRS Technical Report Series TSS Total Suspended Solids TVS Total Volatile Solids USEPA United States Environmental Protection Agency WHO World Health Organization WSP Waste Stabilization Pond yr or y year vi Chapter SANITARY 1 PARASITOLOGY 1.1 Introduction Over the past 40 years, there has been a considerable revival of interest in the use of wastewater for crop irrigation in arid and semi-arid regions as a result of the scarcity of alternative water supplies and the need to increase local food production. Water resources planners have come to recognize the value of this practice, in terms of both water conservation and nutrient recycling and as a method of preventing the pollution of surface and ground water. The public has not objected such practice so long as the necessary health safeguards have been included. In some countries, such as Jordan, Peru and Saudi Arabia, it is government policy to reuse all effluents from sewage-treatment plants, mainly for crop irrigation. The "Health Guidelines for the Use of Wastewater in Agriculture and Aquaculture (TRS, 778) published by WHO (1989), provides guidelines values for health protection. Intestinal nematodes were introduced based on the available epidemiological information supporting the conclusion that helminths present the highest risks of wastewater related disease transmission due to long latency periods with soil stage required for transmission, long persistence in the environment, low infective dose, without practical host immunity. Preparing a document on the subject of sanitary parasitology and the contamination associated with the use of wastewater and sludge in agriculture will serve as a basis for sanitary engineers, microbiologists, and parasitologists on the subject. Based on the most recent technical and scientific information available, identification of helminth eggs is a skill that can be learned quite quickly providing the technician has access to a good microscope with an eyepiece graticule for making measurements and a source of good drawings or photographs. Comprehensive guide on sanitary parasitology does not exist. This guide will bring this information into one volume for easy reference. This guide is intended as