MERS-Cov) AMONG DROMEDARY CAMELS in SELECTED AREAS of AFAR and OROMIA REGION, ETHIOPIA
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EPIDEMIOLOGICAL INVESTIGATION OF MIDDLE EAST RESPIRATORY SYNDROME CORONA VIRUS (MERS-CoV) AMONG DROMEDARY CAMELS IN SELECTED AREAS OF AFAR AND OROMIA REGION, ETHIOPIA MSc Thesis By: Getnet Fekadu Addis Ababa University, College of Veterinary Medicine and Agriculture, Department of Clinical Studies June, 2015 Bishoftu, Ethiopia EPIDEMIOLOGICAL INVESTIGATION OF MIDDLE EAST RESPIRATORY SYNDROME CORONA VIRUS (MERS-CoV) AMONG DROMEDARY CAMELS IN SELECTED AREAS OF AFAR AND OROMIA REGION, ETHIOPIA A Thesis Submitted to the College of Veterinary Medicine and Agriculture of Addis Ababa University in Partial Fulfillment of the Requirements for the Degree of Master of Science in Tropical Veterinary Epidemiology By: Getnet Fekadu June, 2015 Bishoftu, Ethiopia Addis Ababa University College of Veterinary Medicine and Agriculture Department of Clinical Studies As members of the examining board of the final MSc open defense, we certify that we have read and evaluated the thesis prepared by Getnet Fekadu Demissie entitled: Epidemiological Investigation of Middle East Respiratory Syndrome Corona Virus (MERS-CoV) Among Dromedary Camels in Selected Areas of Afar and Oromia Region, Ethiopia and recommend that it be accepted as fulfilling the thesis requirement for the degree of: Masters of Science in Tropical Veterinary Epidemiology. Dr. Tilaye Demissie (Assistant Professor) ___________ _________ Chairman Signature Date Dr. Bekelle Megersa (Associate Professor) ______________ ________ External Examiner Signature Date Dr. Reta Duguma (Associate Professor) _____________ ________ Internal Examiner Signature Date 1. Dr. Fufa Abunna (DVM, MSc, Associate Professor) _____________ ________ Major Advisor Signature Date 2. Dr. Gelagay Ayelet (DVM, MSc, PhD) ______________ ________ Co-Advisor Signature Date Dr. Fufa Abunna (DVM, MSc, Associate Professor) ______________ ________ Department Chairperson Signature Date SIGNED STATEMENT OF DECLARATION First, I affirm that this thesis is my original work and that all sources of material used for this thesis have been duly acknowledged. This thesis has been submitted in partial fulfillment of the requirements for an advanced MSc degree at Addis Ababa University, College of Veterinary Medicine and Agriculture and is deposited at the University/College library to be made available to borrowers under rules of the Library. I solemnly declare that this thesis is not submitted to any other institution anywhere for the award of any academic degree, diploma, or certificate. Name: Getnet Fekadu Signature: ______________ College of Veterinary Medicine and Agriculture, Bishoftu Date of Submission ____________________ ACKNOWLEDGEMENTS First, I would like to praise the Almighty God for all things happened in my life and the things going to happen. My dearest gratitude goes to my Academic advisors Dr. Fufa Abunna and Dr. Gelagay Ayelet for their valuable comments and correction of this paper. Special thanks go to CIRAD for financing of this MERS project and the University of Hong Kong for analysis of the Sera and swab samples collected for this study. I would like to thanks Debebe Shimekit, Mukemil Redi, Samson Tesfaye, Fekadu Demissie, Dawit Fekadu, Mehiret T/Michael, and Rediet Alemayehu for helping me from the beginning to the end of this study. I would like to extend my gratitude also to Dr. Shiferraw Jembere, Mesfin Tadesse, Getahun Demissie, Getachew Nedi, Hawa Mohammed, Abinet Legese, Wubet W/Medhin, Dr. Teferi Degefa, Tezazu Feleke and Bogale Gosaye. Finally I like to thank veterinarian in Afar (Dr. Said Yemer, Yemer, Mekonen, Ali, Hussein, Jemal and Tesfaye) and in Borena (Mekonen and Huqa). i TABLE OF CONTENTS Contents pages ACKNOWLEDGEMENTS ........................................................................................................... i TABLE OF CONTENTS .............................................................................................................. ii LIST OF TABLES ........................................................................................................................ iv LIST OF FIGURES ....................................................................................................................... v ABSTRACT ................................................................................................................................. viii 1. INTRODUCTION .................................................................................................................. 1 2. LITRATURE REVIEW ........................................................................................................ 4 2.1 Definition of MERS ................................................................................................................ 4 2.2 Etiology .................................................................................................................................. 4 2.2.1 Taxonomy and Phylogeny ............................................................................................... 5 2.2.2 Virus Structure and Tropism ........................................................................................... 7 2.3 Epidemiology of MERS-CoV ............................................................................................ 8 2.3.1 Host Range ...................................................................................................................... 8 2.3.2. Transmission ................................................................................................................ 10 2.3.3 Geographical Distribution of MERS-CoV .................................................................... 12 2.4. Pathogenesis of MERS-CoV ................................................................................................ 13 2.5 Clinical Findings of MERS .................................................................................................... 15 2.6. Diagnosis of MERS .............................................................................................................. 16 2.6.1. Serological testes for MERS-CoV ................................................................................ 16 2.7 Treatment of MERS-CoV ..................................................................................................... 18 2.8 Prevention and Control of MERS ...................................................................................... 19 2.9 Current Outbreak of MERS-CoV in South Korea ................................................................ 21 3. MATERIALS AND METHODS ........................................................................................ 22 ii 3.1 Study area and Animals ...................................................................................................... 22 3.2 Study Design and Sampling Technique ............................................................................... 26 3.3 Sample Size .................................................................................................................... 26 3.4 Sample collection, Transportation and storage ........................................................... 27 3.5 Laboratory Analysis ............................................................................................................. 27 3.5.1 Serology ........................................................................................................................ 28 3.5.2 Extraction of RNA and Polymerase Chain Reaction (PCR) ......................................... 29 3.6 Data Analysis ....................................................................................................................... 30 4. RESULTS ............................................................................................................................. 31 5. DISCUSSION ....................................................................................................................... 37 6. CONCLUSION AND RECOMMENDATIONS ............................................................... 39 7. REFERENCE ....................................................................................................................... 40 8. ANNEXES ............................................................................................................................ 44 9. CURRICULLUM VITAE ................................................................................................... 48 iii LIST OF TABLES Tables pages Table 1. Seroprevalence of MERS-CoV in the two age groups (Young and Adult Dromedary camels). .......................................................................................................... 31 Table 2.Seroprevalence of MERS-CoV in the two sex groups of dromedary camels ..... 32 Table 3.Seroprevalence of MERS-CoV in the herd size categories of Dromedary camels ........................................................................................................................................... 32 Table 4. Seroprevalence of MERS-CoV in the two regions (Afar and Oromia) Ethiopia33 Table 5.Seroprevalence of MERS-CoV in different zones of the study area among Dromedary camels ............................................................................................................ 33 Table 6.Seroprevalence of MERS-CoV among Dromedary camels in different districts of Afar and Oromia ............................................................................................................... 34 Table7.Risk factors responsible