Warm-Up

1. Warm-Up • Write about the last time you had a cold. Include the list of symptoms you experienced. Explain how you think you caught the cold and what you did to treat in.

2. Communicable Disease Prevention Lesson 31

3. Objectives • Examine the effects of health behaviors on skin • Examine the relationship between health behaviors and the ways that communicable diseases are spread • Develop and analyze strategies related to the prevention of communicable and non-communicable diseases • Identify available health related services in the community that provide vaccines and information related to disease prevention • Identify the causes, transmission, symptoms and treatment of several communicable diseases • Discuss how public health policies and government regulations influence health promotion and disease prevention

4. Communicable Diseases • Disease that is spread from one living thing to another or through the environment • Causes: • Pathogen: organism that causes disease • Viruses • Bacteria • Fungi • Protozoans • Rickettsias • Infection: condition that occurs when pathogens enter the body, multiply and damage body cell

5. Viruses • Pieces of genetic material surrounded by a protein coat • Need living cells to reproduce • Invade all known forms of life • After the virus penetrates a it takes control of the cell to manufacture more viruses • Antibiotics do not work against viruses

6. Bacteria • Single celled microorganisms • Live almost everywhere on earth • Most are harmless • Multiply through cell division in the body • Some produce a toxin • Substance that kills cells or interferes with their functions • Can be treated with antibiotics

7. Other Types of Pathogens • Fungi • Plantlike organisms • Molds • Yeasts • Some can cause diseases of the skin, mucous membranes or the lungs • Protozoans • Single-celled organisms that are larger and more complex than bacteria • Rickettsias • Pathogens that resemble bacteria • Multiply by invading the cells of another life form • Often enter humans through the bites of insects, such as fleas or lice

8. Figure 24.1 Pg 623 Diseases by Type of Pathogen

9. How Communicable Diseases are Transmitted • Direct Contact: spread by contact with an infected person, animal, or something in the environment • Touching • Biting • Kissing • Sexual contact • Sneezing • Coughing • Indirect Contact: spread indirectly, without being close to an infected person • Contaminated objects: objects that have infectious discharges or secretions, such as a table that someone ahs sneezed on • Vectors: organism, usually an arthropod, such as a tick, that carries and transmits pathogens to humans or other animals • common vectors include flies, mosquitoes and ticks • Water and Food • Airborne Transmission • Pathogens from a sneeze or cough may float in the air for a long time over long distances • Chicken pox, tuberculosis, influenza and anthrax can be spread this way

10. Preventing Communicable Diseases • Physical and chemical barriers make up your body’s first line of defense • Figure 24.1 Pg 628

11. Skin • Epidermis: outer, thinner layer of skin that is composed of living and dead cells • Dermis: thicker layer of skin beneath the epidermis made up of connective tissue and containing blood vessels and nerves • The skin is the first line of defense against many pathogens, however it can be compromised by various actions • Exposure to sun • Body piercing • tattooing

12. Protecting Your Skin • Always wear sunscreen on exposed areas • Use a SPF that is 15 or higher • Use a sunscreen that protects against both UVA and UVB rays • Apply 15 to 30 minutes before going outside • Use even on cloudy days and when participating in winter sports

13. Body Piercing and Tattooing • Result in the physical barrier of the skin being broken • Possibility of bacteria or viruses entering the body increases • Transfer of blood borne pathogens through the use of non-sterile needles • Hepatitis B • Hepatitis C • HIV • If considering getting a piercing or a tattoo consider long term consequences. Make sure you go to a reputable and clean place to decrease chances of disease or infection • Remember, your skin protects you, so harming your skin can harm your entire body…

14. The Immune System • Network of cells, tissues, organs and chemicals that fights off pathogens • 2 major defense strategies • Inflammatory response: reaction to tissue damage caused by injury or infection (general response) • Specific defenses: work against particular pathogens

15. Inflammatory Response • In response to invasion by microorganisms and to tissue damage • Blood vessels near the site expand, allowing more blood flow to the area • Fluid and cells from the bloodstream leak into the area • Collection of fluid and white blood cells causes swelling and pain because of pressure on nerve endings • Phagocyte: white blood cell that attacks invading pathogens • Phagocytes engulf pathogens and then destroy them with chemicals • Pus may collect at the site • Collection of dead white blood cells and damaged tissues • Specific defenses are activated in an effort to prevent this same infection from occurring again

16. Specific Defenses • React to invasion as a result of the body’s ability to recognize certain pathogens and destroy them • Antigen: substance that is capable of triggering an immune response • During the immune response certain types of white blood cells react to these antigens

17. Lymphocytes • Specialized white blood cell that coordinates and performs many of the functions of specific immunity • T Cells • Helper T Cells • Trigger the production of B cells and killer T cells • Killer T Cells • Attack and destroy infected body cells • Don’t attack the pathogen, only the infected cells • Suppressor T Cells • Coordinate the activities of other T cells • “turn off” helper T cells when infection has been cleared • B Cells • Produce antibodies • Proteins that act against specific antigens • Attach to foreign antigens to mark them for destruction • Destroy invading pathogens • Block viruses from entering body cells

18. Memory Lymphocytes • Some T cells and B cells that have been activated by antigens become memory cells • Recognize a former invader • Attack viruses immediately, protecting you from becoming ill • Active Immunity • Immunity your body develops to protect you from diseases • Naturally acquired when your body is exposed to antigens from invading pathogens • Artificially acquired immunity develops in response to a vaccine • Some immunities last a lifetime, but others need to be repeated to maintain immunity • Passive Immunity • Receiving antibodies from another person or animal • Short lived immunity, lasting only weeks to months • Natural passive immunity occurs when antibodies pass from mother to child during pregnancy or while nursing • Artificial passive immunity results fro the injection of antibodies produce by an animal or a human who is immune to the disease

19. Lymphatic System: Figure 24.4 pg 632

20. Care of the Immune System • Eat healthy, making sure to consume nutrient rich foods • Get plenty of rest • Fatigue reduces the effectiveness of the immune system • Get about an hour of physical activity every day • Avoid sharing personal items • Towels, toothbrushes, make up • Avoid tobacco, alcohol and other drugs • Avoid sexual contact • Some STDs, such as HIVE actually destroy the immune system • Keep immunizations up to date

21. Vaccines to Aid the Body’s Defenses • Live-Virus Vaccines • Made from pathogens grown under special laboratory condition to make them lose most of their disease causing properties • The weakened virus can still stimulate the production of antibodies • Vaccines for measles, mumps, rubella and chick pox are produced in this way • Killer-Virus Vaccines • Use inactivated pathogens • Even though they are dead, the organism still stimulate as immune response, producing antibodies • Vaccines for the flu, polio, hepatitis A, rabies, cholera and the plague are produced in this way • Toxoids • Inactivated toxins from pathogens • Used to stimulate the production of antibodies • Many pathogens aren’t harmful themselves, but the toxins they produce are • Tetanus and diptheria immunizations work in this way • New and second generation vaccines • Being developed by scientist using new technologies • Vaccine for hepatitis B is made from genetically altered yeast cells

22. Common Communicable Diseases • Respiratory Infections • Can occur anywhere from the nose to the alveoli of the lungs • Most caused by viruses or bacteria • Common respiratory infections include: • Common cold • Influenza • Pneumonia • Strep throat • tuberculosis

23. The Common Cold • Viral infection • Causes inflammation of the mucous membranes that line the nose and throat • Symptoms: • Runny nose • Sneezing • Sore throat • No cure • Treatments may help to relieve symptoms, and most cold will clear up in a week or so

24. Influenza • The flu • Viral infection of the respiratory tract • Most often spread through airborne transmission • Symptoms: • High fever • Fatigue • Headache • Muscle aches • Cough • Antiviral drugs for treatment are available, but need to be given as soon as the illness arises • Flu vaccination is available in a shot or nasal mist • The Flu can lead to pneumona

25. Pneumonia • An infection of the lungs in which the air sacs fill with pus and other liquid • One of the top 10 causes of death in the US along with the flu • Viral pneumonia is relatively short-lived and produces symptoms similar to those of the flu • Bacterial pneumonia can be treated with antibiotics • Bacteria that cause pneumonia are often present in healthy throats, but when the body defenses are weakened they may get into the lungs and multiply

26. Strep Throat • Bacterial infection spread by direct contact • Symptoms • Sore throat • Fever • Enlarged lymph nodes • Untreated strep throat can lead to serious complications, including inflammation of the kidneys and rheumatic fever, which can cause permanent heart damage • Treated with anitbiotics

27. Tuberculosis • “TB” • Bacterial disease that usually attacks the lungs • Spread through the air when a person with the disease coughs or sneezes • Most people who are infected carry the bacteria in their lungs but never develop the disease • Some strains have developed resistance to antibiotics

28. Hepatitis • A • Another one of the top 10 communicable diseases report in the US • Most commonly spread through contact with feces of an infected person • Symptoms • Fever • Nausea • Vomiting • Fatigue • Abdominal pain • Jaundice: yellowing of the skin and eyes • B • More serious than hepatitis A • Found in bodily fluids of an infected person • Often transmitted through sexual contact • Most people never experience symptoms, however, serious symptoms can occur • Severe liver damage including liver failure and cirrhosis (scarring) of the liver • May be responsible for up to 80% of all cases of liver cancer worldwide • C • Most common chronic blood-borne infection in the US • Transmitted by direct contact with infected blood • Can lead to chronic liver disease, liver cancer and liver failure • Leading reason for liver transplants in the US • No cure

29. Other Common Communicable Diseases: Figure 24.5 pg 640

30. Emerging Infections • Communicable disease whose incidence in humans has increased within the past two decades or threatens to increase in the near future • Factors contributing to the development of emerging infections include: • Transport across borders • Infected people and animals carry pathogens from regions to region • Population movement • Resistance to antibiotics • Changes in food technology • Agents of bioterrorism • Because of the ease and frequency of travel, a contagious bioterrorist agent can spread rapidly from country to country

31. Strategies for Preventing Communicable Disease • Wash Hands • Handle Food Properly • Eat a balanced diet • Avoid sharing utensils • Avoid unnecessary contact with people who are ill • Take care of yourself when you are ill • Get vaccinated against particular disease as recommenced by your physician • Abstain from sexual activity • Learn to manage stress