Component 1: Introduction to Health Care and Public Health in the U.S.

1. Component 1: Introduction to Health Care and Public Health in the U.S. 1.8: Public Health Part II 1.8a: Public Health and Communicable Disease

2. Communicable Disease (CD) • Communicable (also “infectious” or “transmittable”) diseases are those that are a result of organisms such as bacteria, protozoans, fungi, and viruses entering the body • Control of infectious diseases has been mainly due to • clean water and better sanitation – examples are the drastic reduction of typhoid and cholera, scourges of the early 20th century • antimicrobial therapy – examples are control of infections such as tuberculosis and sexually transmitted diseases (STDs) Health IT Workforce Curriculum Version1.0/Fall 2010

3. Public Health Triumphs • Although there continue to be new communicable diseases (see emerging infections, later in this unit), and there is no shortage of existing diseases that are a continued struggle for control (such as tuberculosis, STDs, drug resistant infections, others), two of the brightest triumphs of public health are encouraging - • Polio • Smallpox Health IT Workforce Curriculum Version1.0/Fall 2010

4. Smallpox • Contagious and often fatal, smallpox is caused by a virus that has been around for thousands of years • 1796 Edward Jenner discovered that milkmaids who had caught cowpox did not catch smallpox • 1800: Technique of smallpox vaccination introduced into the US • 1949 - Last case of smallpox in the United States • 1966 - International Smallpox Eradication program established • 1977 - last naturally occurring case in the world, Somalia • 1977 - Worldwide eradication of smallpox following global vaccination program Health IT Workforce Curriculum Version1.0/Fall 2010

5. Smallpox – Current State • Routine vaccination against smallpox among the general public was stopped after eradication • Other than laboratory stockpiles, the variola virus has been eliminated from the world • A valid terrorism concern? • CDC has detailed plan to protect Americans against smallpox as a biological weapon: includes the creation and use of special teams of health care and public health workers to immediately control spread of the disease • Vaccination within 3 days of exposure will completely prevent or significantly modify smallpox for most • US has stockpiled vaccine – it is a live vaccine to a related virus, vaccination involves repeated pricking of skin with a two-pronged needle Health IT Workforce Curriculum Version1.0/Fall 2010

6. Polio • History - evidence of polio in an Egyptian stone engraving over 3,000 years old • Virus that mainly affects children <5 years of age. Spread by contact or by ingestion of fecal contamination in food or water • Highly infectious, the virus invades the nervous system. While up to 95% of people may not even have symptoms, those that do can have severe effects including paralysis • 1955: Salk polio vaccine licensed. Rapid eradication in industrialized countries • Current: Polio has been effectively eliminated in industrialized countries, but still a risk in other countries • World Health Organization (WHO) continues its efforts at global eradication of polio Health IT Workforce Curriculum Version1.0/Fall 2010

7. Public Health Communicable Disease Activities • State and Local Health Department activities include - • Monitor (surveil) incidence of CDs • Investigate outbreaks • Intervene/treat populations • Report data to CDC • CDC activities include: • Gathering national data on infectious diseases • Managing national prevention and surveillance programs • Distributing funding and other resources • Collaborating with state and local public health in outbreak response Health IT Workforce Curriculum Version1.0/Fall 2010

8. Food Poisoning – A Very Simplified Case Study Following is an extremely simplified fictional outbreak investigation. Although the reality is much more complex than this quick example, it does illustrate some of the steps that public health takes in its unending efforts to safeguard the population. • Public Health receives laboratory reports for an enteric disease-causing organism such as Salmonella or Shigella • Public Health Epidemiologists or “disease detectives” investigate the reports • Samples are sent to the Public Health Laboratory to be closely identified • Fieldwork determines that a significant number of ill patients ate at a company picnic • Questionnaires and statistical analyses identify the culprit as contamination in a dairy product served at the picnic • Further investigation reveals a sanitation issue at the dairy has led to contamination in their product • A product recall is issued • The dairy fixes the sanitation problem, and further tests show the product is now free of contamination • Public health reviews and evaluates the study and how to help prevent further such incidences • Data reported to CDC become part of the national data set Health IT Workforce Curriculum Version1.0/Fall 2010

9. Infectious Disease Topics • Animal-Related Diseases  • Bioterrorism Agents/Diseases • Childhood Diseases • Drug Resistant Infections • Emerging Infectious Diseases • Food-Related Diseases • Healthcare-Related Infections and Issues • HIV/AIDS • Insects and Arthropod-Related Diseases • Sexually Transmitted Diseases • Water-Related Diseases Health IT Workforce Curriculum Version1.0/Fall 2010

10. Sampling of Communicable Diseases • Animal-related – example Rabies • A fatal viral infection, caused when the virus is introduced into breaks in skin (such as by an animal bite) • Some Public Health Responses: monitoring, managing treatment, education for responsible pet ownership • Food-related – example E. coli O157:H7 • Bacterial infection usually traced to food contaminated with cow feces. Can lead to very severe health outcomes, including death • Some Public Health Responses: monitoring, interventions, outbreak investigation, education on prevention • Sexually transmitted diseases – example Gonorrhea • Bacterial infection transmitted by sexual contact or during birth. Can lead to permanent health problems. • Some Public Health Responses: monitoring, interventions, outbreak investigation, education on prevention and treatment Health IT Workforce Curriculum Version1.0/Fall 2010

11. Sampling of Communicable Diseases (cont) • Water-related – example Cryptosporidiosis • Microscopic parasite, ingested by drinking water contaminated with animal or human feces • Some Public Health Responses: monitoring, outbreak investigation, education on water treatment • Healthcare-related - example Methicillin-resistant Staphylococcus Aureus (MRSA) • Bacteria resistant to certain antibiotics, in healthcare settings may be introduced by visitors or by health care providers • Some Public Health Responses: monitoring, outbreak investigation, education on prevention for both patients and health care providers • Childhood diseases – example Chickenpox • Viral infection causing fever and itchy rash, highly contagious, spread by coughing, sneezing, contact • Some Public Health Responses: monitoring of disease and vaccinations, outbreak investigation, education on prevention through vaccination Health IT Workforce Curriculum Version1.0/Fall 2010

12. Sampling of Communicable Diseases (cont) • HIV / AIDS – The human immunodeficiency virus (HIV), which can lead to acquired immune deficiency syndrome (AIDS) • Viral infection transmitted by sexual or other body fluid contact • Some Public Health Responses: monitoring of disease and treatments, outbreak investigation, education on prevention and testing • Emerging Infectious Diseases – example Dengue infection • Viral infection, transmitted by mosquito. Endemic to Puerto Rico and many popular tourist destinations in Latin America and Asia. No vaccine or specific medication • Some Public Health Responses: monitoring of disease, outbreak investigation, education on avoidance and mosquito control Health IT Workforce Curriculum Version1.0/Fall 2010