Chapter 17 Infectious Diseases
Lesson 1 What is an infectious disease?
Infectious disease Is any disease that is caused by an agent that can be passed from one living thing to another.
Disease causing organisms Bacterium-strep throat, TB and sinus infection. Virus-cold, influenza Fungus-athlete s foot, ringworm Protozoan-amebic dysentery, malaria Parasite-tapeworm
How infection is spread Sharing food and drink Contact with an infected person Handling objects handled by others
Epidemic Is a wide spread infection from a single source to many people. Example: Cholera-1832 in England
Bacteria Single celled organism that are found almost everywhere. Examples: Tetanus, ulcers, tuberculosis
Antibiotic Drug that slows the growth of the bacteria Discovered by Alexander Fleming-penicillin
Three types of antibiotics Penicillin, Ampicillin erythromycin
Virus Small particle that consists of an outer shell and genetic material. All they can do is to enter a host cell. Example: Herpes HIV/AIDs
Lesson 2 Defenses against infectious diseases
Physical Defense systems Skin Saliva Nasal hairs mucus Tears Mouth Stomach Immune system
Immune system 1-Macrophage engulf the cell that have been infected by the viruses. 2-Macrophage call the T cells and T cells call B cell. 3-B cells produce antibodies which destroy germs. 4-Antibodies attach to other viruses outside of the cells. This signals the cell to destroy the viruses.
immunity When the body builds up antibodies that remember how to fight the germ.
Strong immune system Healthier the body the stronger the immune system.
Lesson 3 Common bacterial infections
Streptococcus Caused by a bacterium
Tuberculosis Cause by a bacterium that is very slow moving organism from a family of bacteria called mycobacterium Kills about 3 million people a year.
Sinus infections Sinusitis when sinuses fill up with mucus and become infected with bacteria.
Lesson 4 Common Viral infections
Common cold The average person has two colds every year.
Influenza The flu is from two different viruses. Influenza A or influenza B.
Vaccine Builds up immunity against different types of diseases.
Mononucleosis A virus called the epstein-barr virus or EBV. This is passed through infected saliva. Also called the kissing disease.
Lesson 5 Sexually transmitted diseases
STD s There are over 75 different kinds of STD s
Sexual abstinence Is the best way not to catch one of these diseases.
Common STD s 1-Chlamydia Some people show no symptoms 2-Human papillomavirus Some people show no symptoms and some have warts 3-Genitital herpes outbreaks are with sores and painful blisters 4-Gonorrhea No symptoms / or abdominal pain 5-Syphilis Sore/fever/swollen lymph nodes 6-Trichomonisasis itching/discharge/painful urination
Problems with STD s Chlamydia- sterility and live infection HPV-cervical cancer in women Genital herpes-deformities in unborn babies Gonorrhea-testicular disease, liver disease, sterility Syphilis-kidney heart and damage, mental illness Trichomoniasis-increase risk of HIV
HIV/AIDS Lesson 6
Aids Acquired immune deficiency syndrome
AIDS Destroys the immune system
HIV Human immunodeficiency virus
Incubation period Time in which you get the disease until symptoms appear.
Combination therapy A combination of several drugs for treatment of the AIDs virus
Opportunistic infections Diseases that happen because of weak immune systems.
Ways to get HIV Sexual contact Sharing needles Blood transfusions-very rare Mother to child
HIV Over 40 million are infected by the virus and 22 million have already died from it.
Lesson 7 Preventing the spread of infectious disease
Protecting yourself from infections Wash your hands and bathe regularly with soap and warm water Avoid contact with people who have a contagious infection. Don t eat someone else's food or drink from someone cup or glass.
Protecting others If you have the flu or a cold wash your hand often. Sneeze into your elbow Stay home from school or work
Getting shots Get your vaccines so that you are immune to many diseases such as: Hepatitis, measles, mumps, rubella, polio, diphtheria, tetanus, pertussis and chickenpox
Chapter 17 Infectious Diseases