Communicable Diseases

1. Communicable Diseases

2. Communicable Diseases Definition • Caused by direct or indirect spread of pathogens from one person to another.

3. Pathogens Definition • -Tiny living creatures that cause disease.

4. Types of pathogens • Bacteria • Virus • Fungi • Protozoan

5. Bacteria • (100 million will fit in a grain of sand.) • Most common of all pathogens. • Most DO NOT cause disease. • Reproduces through cell division. • Ex. Strep throat , lyme disease

6. Strep Throat

7. Bacteria Video http://webcast.mediaondemand.com/library_video/20000901/27_bacteria_300.asx

8. Virus • All viruses are considered Parasites • Smallest and simplest of microorganisms. • Can only live on living cells- tricks human cells to reproduce more viruses. • Reproduce until “cell burst” • Examples- chicken pox, cold, flu, measles, rabies, HIV/AIDS

9. Virus cont. • Highly specific in types of cells they invade. • Polio- nervous system • Common cold –respiratory system • Small pox, chicken pox, shingles- Skin cells. • Antibiotic drugs do not have an affect on viruses.

10. Cell Burst http://www.whfreeman.com/kuby/content/anm/kb03an01.htm • Video • http://www.libraryvideo.com/streaming.asp?mscssid=GQ2BQAMMHCT78JEXX6WWGAQ4EC2M3584&sku=N6639

11. How a virus reproduces • Cell Burst

12. Protozoan • Most are harmless. • One celled organism • Grows in water • Multiples quickly in moist places • Ex. Malaria

13. Fungi • Live off non-living things. • Molds, yeast, and mushrooms • Live in warm moist places. • Ex. Locker room or mats • ex. Ring worm / athletes foot

14. Fungi Athlete’s Foot Ring Worm

15. A. Immune system- Body’s Primary Defenses Against Diseases(nonspecific resistance = will react the same EVERY time a pathogen enters the body) • Skin • Mucus Membrane • Cilia • Chemical barriers – tears and saliva • Reflexes- Blinking, coughing, and sneezing.

16. Body’s Defense Against Communicable Disease • Skin • Most important – keeps out harmful germs • Produces sweat that kills some types of pathogens.

17. Body’s Defense Against Communicable Disease • Mucus Membrane • Cells that line nose, mouth and throat. • Produce mucus to trap germs

18. Body’s Defense Against Communicable Disease • Cilia • Wavelike hairs that sweep out germs

19. Body’s Secondary Defenses • Specific Resistance-more detailed then the primary defense. Kills and keeps record of pathogens. • Fever • White Blood Cells

20. Body’s Defense Against Communicable Disease • Fever • Norm temp. 98.6 • When microorganisms multiply body temp increases. • Temp. increase slows multiplying

21. Body’s Defense Against Communicable Disease • White blood cells • Special cells that fight infection • Kill pathogens by surrounding and swallowing • 1. Lymphocytes = WBC’s (4 types)

22. Lymphocytes • 4 types • Killer T - attack • Are sent to destroy or attack antigens • Helper T – control the strength and quality of immune response • B Cells –produce antibodies • Macrophage- pac man like- take bite of pathogen and sends back info. to T-cells

23. How white blood cells work • Virus enters body system- indirect or directcontact • Macrophage- Bite virus and send antigen to T- cells • Helper T cells – act as messenger calling B cells • B Cells – create antibody to help kill pathogens and remove pathogens (interlocking parts) • Virus can no longer invade body’s cells • Kept on file – body has immunity • Killer T Cells – destroy virus

24. White Blood Cells • Macrophage – • Pac-Man like garbage collectors. • Take bites of invaders

25. Antigens and Antibodies • Antigens- chemical code of pathogens. Contains critical info. about the pathogen • Antibodies 1. Are created by B-Cells 2. Antibodies latch to pathogen. Fits together like a lock and key. This prevents the virus from entering cells

26. Active Immunity • 2 types • Natural – body gets disease & recovers • Recall immune response from previous illness • Vaccination • Dead or weakened strain of virus injected into you body. • Body then destroys virus and creates antibodies against it.

27. Ways Disease Enter Body • Break in skin • Genitals • Mouth • Eyes • Nose

28. How diseases are spread • Direct contact –touching infected area of person • Indirect contact-sneezing, coughing, sharing personal items • Contact with animals and insects - bites • Other contact- eating contaminated foods

29. Prevention for communicable diseases • Wash hand often!!! • Cover mouth when sneezing or coughing. • Proper care of food • Eat healthy and exercise • Shower daily • Avoid tobacco and drugs

31. White blood cells defend against germsThe immune system is made up of many different kinds of white blood cells. White blood cells work together to protect us against disease-causing germs.

32. Macrophages identify germsWhen a germ invades our bodies, macrophages gobble up the germ and display its surface shape, or antigen, for other immune cells to see.

33. Helper T cells direct the defenseHelper T cells spot the foreign antigen on the macrophage and begin to multiply. They alert other white blood cells and direct the body's defense.

34. B cells make antibodiesB cells start to make chemicals called antibodies. Antibodies lock onto foreign antigens making it easier for other immune cells to destroy them.

35. Killer T cells destroy germsAlerted by helper T cells, killer T cells multiply and destroy the invading germs. Working together, our white blood cells can usually destroy invading germs.

36. Problems with Immune System • Immunodeficiency- • System not present or working properly • Some may be caused by medicines ( Chemotherapy) • May be caused by infections (HIV, AIDS)

37. Problems with Immune System • Autoimmune disorders • Immune system mistakenly attacks body’s healthy organs. • Allergic Disorders • System overreacts to exposure to antigens in environment.

38. Common communicable diseases • Common cold –see handout • Hepatitis-see handout • Mononucleosis-see handout

39. REVIEW GAME • RULES- • 1. two teams • 2. three strikes and your out • 3. Must get the question COMPLETELY right in order to earn the points • 4. Two student compete to answer a non-related health question. The winning student asks his team if the want to play or pass…… • 5. Object is the accumulate the most points

40. What are communicable disease? • Diseases that are passed from person to person and caused by a pathogen.

41. Name the pathogen that causes the following diseases? • HIV • Lyme disease • Ringworm

42. How does the following defense work to help protects us from getting sick • Skin- • Mucus member- • Cilia- • Reflexes-

43. Answer to previous ? • Keeps out most pathogens, and produced sweat to kill some pathogens • Produces mucus to trap pathogens • Wave-like hairs that sweep out germs • Blinking, coughing, sneezing

44. Name the four types of pathogens that cause people to become ill? • Bacteria • Virus • Fungi • protozoa

45. Give three examples of how diseases are passed through indirect contact? • Sneezing • Coughing • Sharing personal item, i.e. lip gloss, drinking glass • Person to object • Animal to person, i.e. – deer tick

46. List three characteristics of a virus? • Smallest and simplest of all pathogens • Can only live and reproduce in a living cell • They will only attack specific parts of the body • Will eventually destroy the cell they invade • Tricks human cell to clone the virus

47. Name three ways pathogens can enter the body? • Mouth • Eyes • Nose • Break in the skin • Genitals • ears

48. Name four types of white blood cells? • Lymphocytes • A. Killer T-Cells • B. Helper T-Cells • C. B- Cells • D. Macrophage (pac-man)

49. Name fours ways to prevent communicable disease from spreading? • Wash hands often • Cover mouth when sneezing or coughing • Proper food care- cook food thoroughly • Eat healthy and exercise • Shower daily