Communicable/Infectious Diseases

1. Communicable/Infectious Diseases Unit 8 Page 484

2. Immune System P. 485 Lymphocytes- white blood cells that help the body fight pathogens Two Types: B Cells- produce antibodies T Cells- signal B-cells to produce antibodies

4. Immunity P.485 - the body’s resistance to disease-causing agents. Active- resistance to disease due to the presence of antibodies Passive- introducing antibodies into a persons blood stream Vaccine- weakened disease that is introduced into the body to give immunity (make antibodies)

5. Communicable/Infectious Diseases p. 487 • An illness caused by pathogens that can be spread from one living thing to another. Pathogens- microbes which can cause infectious diseases. Contagious- having the ability to be transmitted. Epidemiology- the study of the source & the spread of diseases.

6. What to know about types of pathogens P. 487 Bacteria- microscopic, single celled org. that cause disease. Fungi(yeast & mold)- simple org., can’t make own food (ex: Athlete’s foot, ringworm) Viruses Protozoa- single celled org., can produce toxins that cause disease. Helminith(worms)- not micro org., cause disease in human body by infecting intestines, muscles, rectum (ex: Round worms or Trichinosis)

7. Microbes- tiny organisms that can not be seen by the naked eye.

8. Bacteria • multiplies in moist, dark, warm, nutrient-rich body tissue. (can also live and multiply outside the body) • microscopic, single celled organisms that can cause disease. Tetanus, Tuberculosis(492) & Lyme disease, Strep Throat, Syphilis and Gonorrhea are all caused by bacteria.

9. Viruses Viruses are not cells! Viruses cause diseases by invading cells forcing them to reproduce viruses. Some remain in the body for life. Can live outside the body for a short time but must multiply inside. * Smallest disease causing pathogen Examples: rabies, polio, common cold, hepatitis, mumps, chicken pox, shingles and warts.

10. How Pathogens are SpreadP.488

11. Possible Causative Factors • Host- person who is ill, & is carrying the virus. • Environment- where the host lives. • Time- season of the year. • Agent- germ which caused the illness. Susceptible: having a high chance of getting disease. Relapse: recurrence of symptoms of disease after a period of improvement.

12. Defense Against InfectionP.485 First Line of Defense- Structural 1. Skin (unbroken) 2. Mucous Membranes in the mouth, nose and bronchial tubes. 3.Cilia 4. Digestive Juices (stomach acids) 5. Tears

13. Second Line of Defense- Cellular • White Blood Cells Phagocytes- eat up invaders • Lymph Nodes- gland like structures that serve as filters to screen out bacteria. Immunity- Last Line of Defense T-cells: lymphocytes recognize invaders and activate B-cells B-cells: responsible for producing antibodies that destroy invading germs. Inborn Immunity- temporary immunity that an infant has.(acquired from mothers antibodies)

14. Bacterial STD’sP.499 Chlamydia- PID- Pelvic Inflammatory Disease Syphilis- chancre appears, if it goes away doesn't mean STD is gone, its dormant. Spirochete- bacteria that causes syphilis Gonorrhea- Gonococcus- bacteria that causes gonorrhea * Bacterial STD’s are curable with antibiotic

15. Viral STD’sP.502 Herpes I- blisters or sores appear on or around the mouth Herpes II- causes blisters to appear in genital region. HPV- wart in genital area (can cause cervical cancer in females) Hepatitis (A,B,C,D,E)- viral infection of the liver Parasites Pubic Lice- Trichomoniasis-

16. HIV P. 504 Transmissible virus that attacks T-cells of the immune system and causes immune deficiency. • the virus that causes AIDS. Some people who become infected with HIV, become ill & die within six months. Others may remain in good health and show no signs for six to ten years. Opportunistic Infections- infections like pneumonia or cancer, that actually kill the person because immune system is so low due to HIV.

17. Ways of Transmission P. 506 List the 7 ways- -Contact with infected blood, semen, or vaginal secretions. -Injection of infected blood or blood products -Infected mother to baby (breast milk) High Risk Behaviors: Anal intercourse, injecting needles with multiple users, vaginal intercourse. Other Risky Behaviors: oral sex, receiving blood (not too probable in this day and age) ** Ways HIV is not transmitted

19. How HIV Takes Over the BodyP.505 The virus destroys the T cells& disables their function of signaling the B cells to produce antibodies. With the immune system so low, the T cells are not able to fight off other microorganisms & cancer cells. The HIV cells multiply.

20. Early Signs of HIV • Tiredness • Skin rashes • Night sweats • Loss of weight • Diarrhea • Sore throat & fever

21. Incubation Period Word given for the time period when you turn from HIV- to HIV+ It may take 6 weeks to 6 months before HIV antibodies will show up in the blood. Most people develop antibodies in 6-12 weeks. Treatment Drugs- slows down the germs ability to reproduce. P. 510 Cure- none

22. Tests P. 512 ELISA- blood test that identifies whether a person has HIV antibodies. If negative- retest in 6 months, if positive- another ELISA is done to confirm. Western Blot Test- this is also an antibody test done to confirm the results of the ELISA test.

23. AIDSAcquired Immune Deficiency Syndrome - the last and deadly stage of HIV is AIDS. When a person has 200 T cells or less they are considered to have AIDS. After symptoms marking the beginning of AIDS development, most people die within two years & the rest within five years.

24. Avoiding STD’s & HIV P. 508