© 2007 McGraw-Hill Higher Education. All rights reserved. Chapter Twenty Infectious Diseases: Prevention and Management

© 2007 McGraw-Hill Higher Education. All rights reserved. What is an Infection? A disease or condition caused by a micro- organism Micro-organisms are the tiniest living organisms on earth that eat, reproduce, and die An infection is considered an illness or disease if it interferes with your usual lifestyle or shortens your life

© 2007 McGraw-Hill Higher Education. All rights reserved.

Types of Pathogens [Figure 20.2] Viruses Bacteria Prions Fungi Helminths Protozoa Ectoparasites

© 2007 McGraw-Hill Higher Education. All rights reserved.

Immunization Once a person has survived infection by a pathogen, they often acquire immunity to future infections by the same pathogen B and T cells become memory cells when exposed to the agent, which allows recognition and quick action to destroy the invader before the illness begins A vaccine is a preparation of weakened or killed micro-organisms which serve two functions: Protect by stimulating an immune response Protect society by decreasing the incidents of disease

© 2007 McGraw-Hill Higher Education. All rights reserved. Controllable Risk Factors for Infection Eating a balanced diet Proper exercising Proper sleep Managing stress properly Receiving vaccinations, when available

© 2007 McGraw-Hill Higher Education. All rights reserved. Uncontrollable Risk Factors for Infection Age Structural body differences Undergoing surgical procedures Having Chronic illnesses Genetic predispositions Socio-cultural issues Poverty Demographics Healthcare access

© 2007 McGraw-Hill Higher Education. All rights reserved. Disruption of Immunity Occasionally, the immune system can malfunction due to the following: Autoimmune Diseases –Mistaken identity in the body that allows the immune system to create an immune response, causing damage to body cells and tissues Allergies –Body identifies a harmless foreign substance as an antigen and creates an immune response Stress –Long term stress can suppress the immune system, causing illness

© 2007 McGraw-Hill Higher Education. All rights reserved. What are Technology-related Changes that Affect Disease Transmission? Blood Products –Blood banks in the US and Canada screen for known infections, however when new infections arise this can affect people needing blood products nationwide Food Production and Distribution –Food is shipped nationwide in mass quantities which could pose a risk of spreading infections through contaminated food products or handling

© 2007 McGraw-Hill Higher Education. All rights reserved. What are Behavior-related Changes that Affect Disease Transmission? Travel and Disease SARS Outbreak (2003) Sexual Behavior and Disease Sexually Transmitted Diseases Illicit Drug Use Use of contaminated needles and syringes Tattoos and Body Piercing Equipment re-use risk factor for spreading contamination

© 2007 McGraw-Hill Higher Education. All rights reserved. Reemerging and New Diseases Tuberculosis Small Pox Pneumonia Whooping cough Polio Ebola and Marborg Hemorrhagic Fevers West Nile Virus Hantavirus

© 2007 McGraw-Hill Higher Education. All rights reserved. Major STDs HIV Chlamydia Gonorrhea Pelvic Inflammatory Disease Human Papillomavirus Genital Herpes Hepatitis Syphilis

© 2007 McGraw-Hill Higher Education. All rights reserved. HIV/AIDS Cause – HIV, virus that attacks the helper T cells (CD4) and macrophages of the immune system –HIV-1 is the predominant strain in the United States and Canada –HIV-2 is a different strain, primarily found in Africa Method of Transmission: –direct contact involving the exchange of bodily fluids (blood, semen, vaginal secretions) –sharing of hypodermic needles –through infected blood products –perinatal transmission (mother to fetus)

© 2007 McGraw-Hill Higher Education. All rights reserved. HIV/AIDS Symptoms Most infected people are asymptomatic or can remain symptom-free for years, even though antibodies have been formed within weeks of infection Eventually the following symptoms may appear: –tiredness –fever –loss of appetite/weight –diarrhea –night sweats –swollen glands (neck, armpit, groin)

© 2007 McGraw-Hill Higher Education. All rights reserved. HIV Testing Enzyme Immune Assay (EIA) Antibodies detection method Enzyme Linked Immunosorbent Assay (ELISA) Antibodies detection method Western BLOT test Confirmation test eliminating false positives Home Access Express HIV-1 (home test kit) Finger prick method

© 2007 McGraw-Hill Higher Education. All rights reserved. Management for HIV/AIDS No cure at this time Antiretroviral agents Drug Cocktails New Treatment Possibilities Microbicide (kills micro-organisms)

© 2007 McGraw-Hill Higher Education. All rights reserved. Other Major STDs Chlamydia Gonorrhea Pelvic Inflammatory Disease Human Papillomarvirus Genital Herpes Hepatitis (A, B, C) Syphilis

© 2007 McGraw-Hill Higher Education. All rights reserved. Other STDs Trichomoniasis Bacterial Vaginosis Candidiasis Urinary Tract Infection Pubic Lice and Scabies

© 2007 McGraw-Hill Higher Education. All rights reserved. Prevention and Treatment of Infectious Diseases Support your immune system by eating a balanced diet, exercising, sleep, managing stress and not smoking Vaccinate yourself and children Be proactive when you have been exposed to an infectious disease Minimize your use of antibiotics Practice the ABC’s of safer sex Learn about common infectious diseases if you are about to travel to a particular high risk area Participate in efforts to reduce the likelihood of infectious diseases in your community

© 2007 McGraw-Hill Higher Education. All rights reserved. Chapter Twenty Infectious Diseases: Prevention and Management