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MEDICAL LABORATORY STUDENTS

Mwamisi, Muthwii, Mwala, Mokua To the Reader

Virology is an important subject in Sciences. Medical Laboratory puts a technologist/technician in the fore front in diagnosis and proper interpretation of the correct diseases by a clinician. Research on viruses, therefore, has gained a lot of momentum in recent years due to the Medical importance they contribute to the field of medicine. A lot of this work goes through the medical laboratory Department where it is handled by the medical laboratory students, especially, on practical experience.

The purpose of this manual is, therefore, to provide to the student adequate up-to-date information in preparation for the work that the student will perform in any Medical Laboratory Department, whether research or routine work.

We hope this information will not only be useful to the medical laboratory Students or staff, but!also will be a reference material for others in Health or health related field.

Joseph M. Mwamisi, PhD Samson M. Muthwii PhD Denis M. Mwala M.Se. John M. Mokua M.Se.,

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2 TABLE OF CONTENTS

1. VIROLOGY 6 1.1 Definition of Virology 6 1.2 Definition of Viruses 6 1.3 Differences between Bacteria and Viruses 7 1.4 Morphology of Viruses 7 2. CLASSIFICATION OF VIRUSES 9 2.1 Classification 9 Epidemiological Analysis 9 Physical and Chemical Properties Analysis 9 DNA Viruses 9 RNA Viruses 9 Enteric Viruses 10 Respiratory Viruses ' 10 Arthropod-Borne Viruses () 10 2.2. DNA Viruses 10 Poxvirusae 10 Ridoviridae 10 2.3. RNA Viruses 10 Picornaviridae 11 3. CULTIVATION OF ANIMAL VIRUSES 11 Introduction: : 11 Laboratory Animals 11 Tissue Culture 12 Cell Culture : 12 Primary Cells 12 Diploid Cells 12 Stable Cell Line 13 Recognition of Viral Growth in Cell Culture 13 Assay of Animal Viruses 13 4. MULTIPLICATION OF ANIMAL VIRUSES 15 Introduction 15 Replication of Viral RNA 16 Synthesis of Capsid 17 Assembly and Release 17

5 PATHOGENICITY OF ANIMAL VIRUSES 17 Cytopathic Effect (CPE) 17 Change of Cell Membrane 17 Inclusion Body 18

3 Transformation 18 Interferon 18 Persistent Infection of Cultured Cells 18 Immunoglobulin 19 6 DEVELOPMENT OF IMMUNITY AND IMMUNOGLOBULIN ANTI BODY PRODUCTION 21 Process of Virus Infection in Man 21 Reaction of Virus Infection in Host.. 21 Natural Resistance 21 Immunological responses 22 Neutralization of Virus with Antibody 22 6.1 Viral Vaccine 23 7. CHEMOTHERAPY 24 8. THE MAIN TYPE OF INFECTIVE ILLNESS (DIFFERENT TYPES OF VIRUSES) 25 DNA Viruses , 25 8.1 Poxviruses 25 8.2. Herpes Viruses 25 8.3 Herpes Simplex 26 Type 1 26 8.4 Herpetic Whitlow 26 8.5 Variola Virus (Smallpox Virus) 27 a) Microscopy of fluid from pox, to detect virus particles 28 8.6 Varicella - Zoster Virus 28 8.7 Cytomegalovirus (Salivary Gland Virus) 29 8.8 RNA Viruses 33 Sub-types of 'A' 34 Clinical Sign 34 8.9 Virus Pneumonia 35 8.10 Paramyxoviruses ; 35 8.11 Measles Viruses 36 8.12 Mumps Virus 37 8.13 Para influenza Viruses 38 8.14 Respiratory Syncytial (RS) Virus 39 9 PICORNA VIRUSES 40 Polioviruses 40 10 ECHOVIRUSES 44 , 11. RHINOVIRUSES 45 12. REOVIRUSES: (RESPIRATORY ENTERIC ORPHAN VIRUSES) 46

4 Reoviruses 46 Cornaviruses 47 Rhabdoviruses 47 13. RABIES VIRUS 48 14. ARBOVIRUSES 50 15. FLA VIVIRUSES 51 16. UNCLASSIFIED VIRUSES 54 16.1 Rubella Virus (German Measles) 54 16.2 Hepatitis B ( Hepatitis Virus) 57 16.3. Non-A / Non-B Hepatitis 59 16.4. Virus Encephalitis 59 16.5. Yellow Fever 59 17. CULTURES AND OTHER METHODS 60 17.1 Cell Culture 62 17.2 Cloning: Colony Formation Method 64 18. LABORATORY DIAGNOSTIC TECHNIQUES: 70 19. SPECIMEN COLLECTION FOR VIRAL INFECTIONS INVESTIGATION76 19.1 Discoveries and Isolations of Viruses 87 1 20 SELECT TERMINOLOGIES 88 REFERENCES 100

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