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OS Obisesan Orcid.Org 0000-0003-2165-3636 Molecular Prevalence of HSV1/2 from HIV-1 Positive and HIV-1 Negative sera collected from North-West and KwaZulu-Natal Provinces OS Obisesan Orcid.org 0000-0003-2165-3636 Dissertation submitted in fulfilment of the requirements for the degree Master of Science in Biology (Medical Virology) at the North West University Supervisor: Prof. NP Sithebe Co-Supervisor: Dr. L Makhado Examination: November 2018 Student number: 27521680 Table of Contents Table of Contents ..................................................................................................................................... i LIST OF FIGURES ...................................................................................................................................... v LIST OF TABLES ...................................................................................................................................... vii DECLARATION ........................................................................................................................................ ix ACKNOWLEDGEMENTS .......................................................................................................................... xi ABSTRACT .............................................................................................................................................. xii LIST OF ABBREVIATIONS .......................................................................................................................xiv DEFINITIONS OF TERMS ........................................................................................................................xvi CHAPTER 1 .............................................................................................................................................. 1 1.0 INTRODUCTION AND LITERATURE REVIEW ...................................................................................... 1 1.1 Introduction ...................................................................................................................................... 1 1.1.1 Research Aim and Objectives..................................................................................................... 2 1.1.1.1 Research Aim ...................................................................................................................... 2 1.1.1.2 Research Objectives ............................................................................................................ 2 1.1.2 Problem Statement .................................................................................................................... 3 1.1.3 Significance of the Research Study ............................................................................................ 3 1.2 Literature Review of Herpes Simplex Viruses (HSV) ......................................................................... 4 1.2.1 Introduction ............................................................................................................................... 4 1.2.2 Virology of Herpes Simplex Viruses ........................................................................................... 4 1.2.2.1 Classification of HSV ............................................................................................................ 4 1.2.2.2 Morphology and Genomic Organisation of Herpes Simplex Virus ..................................... 5 1.2.2.3 Genomic organisation of Herpes simplex virus .................................................................. 7 1.3 Life Cycle and Pathogenesis of Herpes Simplex Virus ....................................................................... 8 1.3.1 Life cycle of Herpes Simplex Virus ............................................................................................. 8 1.3.1.1 Viral entry ............................................................................................................................ 8 1.3.1.2 Gene expression .................................................................................................................. 9 1.3.1.3 Replication .......................................................................................................................... 9 1.3.1.4 Latency and Immune Evasion ........................................................................................... 10 1.3.2 HSV Pathogenesis..................................................................................................................... 11 1.3.2.1 Immune Response to HSV ................................................................................................. 12 1.4 Epidemiology of Herpes Simplex Virus ........................................................................................... 14 1.5 Transmission of Herpes Simplex Virus ............................................................................................ 18 1.6 Virus Infection and Diseases ........................................................................................................... 19 i 1.6.1 Herpes Simplex Virus Infection ................................................................................................ 19 1.6.1.1 Lytic Infection .................................................................................................................... 19 1.6.1.2 Lysogenic Infection ........................................................................................................... 19 1.6.2 HSV Diseases ............................................................................................................................ 20 1.6.2.1 Herpes Keratitis ................................................................................................................. 20 1.6.2.2 Neonatal Herpes ............................................................................................................... 20 1.6.2.3 Infection of the Central Nervous System (CNS) ................................................................ 21 1.6.3 Laboratory Diagnosis of Herpes Simplex Virus ........................................................................ 21 1.6.3.1 Indirect Serological tests ................................................................................................... 23 1.6.4 Signs and Symptoms ................................................................................................................ 25 1.7 Factors Associated with HSV Infection ........................................................................................... 25 1.8 Human Immunodeficiency Virus (HIV) ............................................................................................ 26 1.8.1 Introduction ............................................................................................................................. 26 1.8.2 Epidemiology of HIV ................................................................................................................. 26 1.8.3 HIV Transmission ...................................................................................................................... 28 1.8.4 HIV Pathogenesis ..................................................................................................................... 29 1.8.5 Structure and Replication of HIV ............................................................................................. 29 1.8.6 HIV Replication Cycle ............................................................................................................... 31 1.9 HSV/ HIV Coinfection .................................................................................................................. 3332 1.9.1 Epidemiological Relationship of HSV and HIV ...................................................................... 3433 1.10 Treatment of HSV ...................................................................................................................... 3433 CHAPTER 2 ............................................................................................................................................ 36 2.0 MATERIALS AND METHODS ............................................................................................................ 36 2.1 Research Design .............................................................................................................................. 36 2.2 Ethical Clearance ............................................................................................................................. 36 2.3 Sample Collection ........................................................................................................................... 36 2.4 Methods .......................................................................................................................................... 36 2.4.1 Screening for HSV Using Enzyme Immunoassay Kits (ELISA) ................................................... 36 2.4.2 Screening for HIV Using ELISA .................................................................................................. 37 2.5 Analysis using Molecular Techniques ............................................................................................. 37 2.5.1 DNA extraction using QIAamp® MinElute® Virus Spin kit: ....................................................... 37 2.5.2 RNA extraction using QIAamp® Viral RNA Mini kit (50): .......................................................... 38 2.6 Control materials ...........................................................................................................................
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