1. Section 21.3 Common Infectious Diseases Slide 1 of 26 Objectives Identify some diseases caused by bacteria and by viruses. Describe behaviors that can help you get healthy and stay healthy. Section 21.3 Common Infectious Diseases

2. Section 21.3 Common Infectious Diseases Slide 2 of 26 Health Stats Note the difference between the leading causes of death in the United States in 1900 and in 2000. Were any of the leading causes of death in 2000 infectious diseases? Explain why you think this is the case.

3. Section 21.3 Common Infectious Diseases Slide 3 of 26 There are thousands of infectious diseases, and over 40 kinds commonly occur in the United States. Bacterial Diseases Four infectious diseases caused by bacteria are strep throat Lyme disease meningitis tuberculosis

4. Section 21.3 Common Infectious Diseases Slide 4 of 26 “Strep” is short for Streptococcus, the bacterium that causes the disease. Strep Throat Strep bacteria, which are usually found in the nose and throat, can be spread by contact with mucus from an infected person. Symptoms include sore throat swollen lymph nodes on the sides of the neck headache fever

5. Section 21.3 Common Infectious Diseases Slide 5 of 26 Humans can become infected with the bacteria that cause Lyme disease when they are bitten by an infected tick. Lyme Disease Symptoms of Lyme disease include The best way to protect yourself from Lyme disease is by avoiding tick bites. a red rash at the site of the tick bite fever chills body aches

6. Section 21.3 Common Infectious Diseases Slide 6 of 26 An infection of the fluid in the spinal cord and the fluid that surrounds the brain is called meningitis. Bacterial Meningitis Symptoms of meningitis include high fever, headache, vomiting, and a stiff neck. There are two types of meningitis—one is caused by bacteria, the other by a virus.

7. Section 21.3 Common Infectious Diseases Slide 7 of 26 A highly contagious bacterial infection of the lungs is tuberculosis (too bur kyuh LOH sis), or TB. Tuberculosis It is transmitted when droplets from an infected person’s cough or sneeze are inhaled. Symptoms, which include fatigue, weight loss, a mild fever, and a constant cough, may not show up for many years after the initial infection.

8. Section 21.3 Common Infectious Diseases Slide 8 of 26 An antibiotic (an tih by AHT ik) is a drug that inhibits or kills bacteria. Treating Bacterial Diseases Using antibiotics exactly as they are prescribed is very important to prevent bacteria from developing resistance to the medicine. Antibiotic resistance can result if you don’t finish your prescription and some of the bacterial pathogens in your body survive.

9. Section 21.3 Common Infectious Diseases Slide 9 of 26 Viral diseases include Viral Diseases the common cold influenza pneumonia hepatitis

10. Section 21.3 Common Infectious Diseases Slide 10 of 26 The common cold is really a group of symptoms that is caused by a number of different viruses. The Common Cold One or two days after exposure to a cold virus, people develop sneezing sore throats runny noses coughing chest congestion fever headaches muscle aches Colds spread when a person touches a contaminated object or inhales droplets from a sneeze or a cough.

11. Section 21.3 Common Infectious Diseases Slide 11 of 26 The flu, or influenza, is a common viral infection of the upper respiratory system. Influenza Influenza is spread by airborne droplets and contact with contaminated objects. High fever, sore throat, headache, and a cough are typical symptoms of the flu.

12. Section 21.3 Common Infectious Diseases Slide 12 of 26 The Stages of the Flu

13. Section 21.3 Common Infectious Diseases Slide 13 of 26 In people who are elderly, or who have heart disease or breathing problems, flu may develop into pneumonia (noo MOHN yuh), a serious infection of the lungs. Pneumonia Many people die each year from pneumonia, which can be caused by viruses, bacteria, or even fungi.

14. Section 21.3 Common Infectious Diseases Slide 14 of 26 A group of viruses that infect the liver can cause hepatitis (hep uh TY tis), or inflammation of the liver. Hepatitis Symptoms of hepatitis include fever nausea pain in the abdomen jaundice (JAWN dis), or yellowing of the skin. Hepatitis A is transmitted in human wastes and in contaminated water and food. Hepatitis B can be transmitted in blood, during sexual contact, or during tattooing or body piercing. Hepatitis C can be transmitted in blood, during sexual contact, or during tattooing or body piercing.

15. Section 21.3 Common Infectious Diseases Slide 15 of 26 In most cases, there is no particular medicine that can cure a viral infection. Treating Viral Diseases The best treatments for viral infections are rest, a well-balanced diet, and plenty of fluids. Many over-the-counter medicines can treat the symptoms of viral infections.

16. Section 21.3 Common Infectious Diseases Slide 16 of 26 Click above to go online. For: Updates on infectious diseases

17. Section 21.3 Common Infectious Diseases Slide 17 of 26 Evaluating Antibacterial Products Products claiming to rid your home of pathogens seem to be everywhere. Do you think these products stand up to their claims? Evaluate products claiming to have antibacterial action using this questionnaire.

18. Section 21.3 Common Infectious Diseases Slide 18 of 26 A “Yes” answer to one or more questions indicates that the product may not live up to its claims. Does the product claim to inhibit or destroy all pathogens? Does the product seem to be using scare tactics to get you to buy it? Does the product use nonscientific words, such as “germs” or “bugs”? Do the benefits sound too good to be true? Are the ingredients identical to those in non-antibacterial products?

19. Section 21.3 Common Infectious Diseases Slide 19 of 26 Evaluating Antibacterial Products Choose a product from a local store that claims to be antibacterial. Devise an experiment to test the effectiveness of the product.

20. Section 21.3 Common Infectious Diseases Slide 20 of 26 When you do get sick, you can help your body recover by going to bed and resting. Getting Healthy, Staying Healthy This treatment and well-balanced meals are all that you need to recover from most mild infections.

21. Section 21.3 Common Infectious Diseases Slide 21 of 26 If you are worried about your health for any reason, see a doctor and discuss your concerns with him or her. When to Seek Medical Care Seek professional medical care if you have an extremely sore throat, earache, vomiting, diarrhea, or a temperature of 101°F that lasts more than two days mucus from your nose or throat that is thick and yellowish green difficulty breathing, or severe pain anywhere a cut, scrape, or sore that does not seem to be healing as it should an illness that lasts longer than usual

22. Section 21.3 Common Infectious Diseases Slide 22 of 26 You can protect yourself from infectious diseases in three ways Preventing Infectious Diseases avoiding contact with pathogens making sure that your immunizations are current choosing healthful behaviors

23. Section 21.3 Common Infectious Diseases Slide 23 of 26 Here are some healthful behaviors you should practice to help you avoid disease. Preventing Infectious Diseases Wash your hands several times a day, especially before eating and after using the bathroom. Do not share items that can transfer pathogens, such as towels, eating utensils, cups, or hairbrushes. Cook and store foods properly. Meats should be cooked thoroughly. Hot foods should be kept hot, and cold foods should be kept cold. Avoid close contact with people who are ill.

24. Section 21.3 Common Infectious Diseases Slide 24 of 26 Here are some healthful behaviors you should practice to help you avoid disease. Preventing Infectious Diseases Stay home when you are not feeling well. Learn to manage stress in healthful ways, and get at least eight hours of sleep each night. Eat well-balanced meals, and do not skip meals. Exercise regularly, at least three or more times a week. Avoid unhealthful substances, such as tobacco, alcohol, and illegal drugs.

25. Section 21.3 Common Infectious Diseases Slide 25 of 26 Vocabulary antibioticA drug that inhibits or kills bacteria.

26. Section 21.3 Common Infectious Diseases Slide 26 of 26 QuickTake Quiz Click to start quiz.

27. Section 21.3 Common Infectious Diseases Slide 27 of 26 End of Section 21.3 Click on this slide to end this presentation.