Human Diseases A Systemic Approach CHAPTER Infectious Diseases Human Diseases A Systemic Approach Seventh Edition Mark Zelman Elaine Tompary Jill Raymond Paul Holdaway and Mary Lou Mulvihill Copyright 2010 by Pearson Education Inc Upper Saddle River New Jersey 07458 All rights reserved Chapter 3 Objectives Define Infectious Disease ID and terminology related to the study of ID Discuss transmission control of transmission treatment of ID Describe and compare the characteristics of various categories of infectious agents prions viruses bacteria protozoa fungi and helminths Define and discuss nosocomial infections Discuss antibiotic resistance and appropriate use of antibiotics Discuss re emerging Infectious Disease Human Diseases A Systemic Approach Seventh Edition Mark Zelman Elaine Tompary Jill Raymond Paul Holdaway and Mary Lou Mulvihill Copyright 2010 by Pearson Education Inc Upper Saddle River New Jersey 07458 All rights reserved Terminology Epidemiology is the study of the transmission occurrence distribution and control of disease Incidence without knowing how many are occurring at one time you don t know if things are getting better or worse the number of new cases of a disease in a population in a specified period of time Prevalence know difference between incidence and prevalence for exam the number of existing cases of a disease in a population at a specific point in time Human Diseases A Systemic Approach Seventh Edition Mark Zelman Elaine Tompary Jill Raymond Paul Holdaway and Mary Lou Mulvihill Copyright 2010 by Pearson Education Inc Upper Saddle River New Jersey 07458 All rights reserved 7HUPLQRORJ FRQW G Endemic A disease is ZKHQ it always occurs at low levels in a population Epidemic A disease is an LI it occurs in unusually large numbers over a specific area Pandemic A LV ZKHQ an epidemic has spread to include larger geographic areas Human Diseases A Systemic Approach Seventh Edition Mark Zelman Elaine Tompary Jill Raymond Paul Holdaway and Mary Lou Mulvihill Copyright 2010 by Pearson Education Inc Upper Saddle River New Jersey 07458 All rights reserved 7HUPLQRORJ FRQW G Types of Infectious Disease Communicable transmitted from human to human either directly or indirectly Noncommunicable not transmitted directly from humans Human Diseases A Systemic Approach Seventh Edition Mark Zelman Elaine Tompary Jill Raymond Paul Holdaway and Mary Lou Mulvihill Copyright 2010 by Pearson Education Inc Upper Saddle River New Jersey 07458 All rights reserved 7HUPLQRORJ FRQW G Reservoir LV the source of an infectious agent Examples include humans animals insects soil and water Horizontal transmission happens when an ID is transmitted directly from an infected person to a susceptible person Vertical WUDQVPLVVLRQ occurs from one generation to the next Fomites are inanimate objects that are contaminated by direct contact with the reservoir Human Diseases A Systemic Approach Seventh Edition Mark Zelman Elaine Tompary Jill Raymond Paul Holdaway and Mary Lou Mulvihill Copyright 2010 by Pearson Education Inc Upper Saddle River New Jersey 07458 All rights reserved Methods of Transmission Communicable Disease CD Direct transmission Direct physical contact e g sex Droplet spread e g coughing sneezing Indirect transmission through an intermediary mechanism Contaminated food or water Vectors ex mosquito can carry infected blood from one person to other Fomites ex door handle Human Diseases A Systemic Approach Seventh Edition Mark Zelman Elaine Tompary Jill Raymond Paul Holdaway and Mary Lou Mulvihill Copyright 2010 by Pearson Education Inc Upper Saddle River New Jersey 07458 All rights reserved Methods of Control CD break transmission Must to eradicate or control CD 1 Immunization 2 identify isolate treat 3 Controlling indirect transmission Human Diseases A Systemic Approach Seventh Edition Mark Zelman Elaine Tompary Jill Raymond Paul Holdaway and Mary Lou Mulvihill Copyright 2010 by Pearson Education Inc Upper Saddle River New Jersey 07458 All rights reserved 0HWKRGV RI RQWURO FRQW G Controlling indirect transmission contaminated food or water chlorination of water supplies sewage Effective facilities standards and laws for handling manufacturing and distributing commercially prepared foods control and or eradication of vectors Human Diseases A Systemic Approach Seventh Edition Mark Zelman Elaine Tompary Jill Raymond Paul Holdaway and Mary Lou Mulvihill Copyright 2010 by Pearson Education Inc Upper Saddle River New Jersey 07458 All rights reserved Examples of Methods of Control A Unimpeded direct or indirect transmission of a communicable disease from person to person B Immunization protects a susceptible person by conferring resistance to infection C Isolation and prompt treatment of the infected person prevent the spread of disease to susceptible persons D Control of indirect transmission blocks spread of infectious agent Human Diseases A Systemic Approach Seventh Edition Mark Zelman Elaine Tompary Jill Raymond Paul Holdaway and Mary Lou Mulvihill Copyright 2010 by Pearson Education Inc Upper Saddle River New Jersey 07458 All rights reserved Categories of Infectious Agents Prions Viruses Bacteria Protozoa Fungi Helminths Human Diseases A Systemic Approach Seventh Edition Mark Zelman Elaine Tompary Jill Raymond Paul Holdaway and Mary Lou Mulvihill Copyright 2010 by Pearson Education Inc Upper Saddle River New Jersey 07458 All rights reserved Prions An infectious agent composed only of protein Induces abnormal folding of normal cellular proteins in the brain rapidly Usually progress and are untreatable fatal currently and Prions are responsible for Creutzfeldt Jakob Disease this is the worst one Kuru Disease Human Diseases A Systemic Approach Seventh Edition Mark Zelman Elaine Tompary Jill Raymond Paul Holdaway and Mary Lou Mulvihill Copyright 2010 by Pearson Education Inc Upper Saddle River New Jersey 07458 All rights reserved Viruses Core genetic material RNA or DNA capsid enclosed in a Does not independently grow metabolize or reproduce Carries out life processes by entering redirecting cells and energy materials and organelles metabolism activities Human Diseases A Systemic Approach Seventh Edition Mark Zelman Elaine Tompary Jill Raymond Paul Holdaway and Mary Lou Mulvihill Copyright 2010 by Pearson Education Inc Upper Saddle River New Jersey 07458 All rights reserved Bacteria One celled organisms nucleus Small no or membranous organelles prokaryote Able to adapt and survive in a