1. Chapter 10 Airborne Bacterial Diseases

2. 10.1 Structure and Indigenous Microbiota of the Respiratory System Upper respiratory defenses limit microbe colonization of the lower respiratory tract. Microbial colonization is usually limited to the upper respiratory tract. Mucociliary clearance traps microbes and particulates larger than 2 µm in a layer of mucus. Figure 3 Respiratory System Anatomy

3. FIGURE 4: Staphylococcus in the Ciliated Epithelium © Juergen Berger/Photo Researchers, Inc. Ciliated epithelial cells move mucus to the pharynx where it is swallowed and sent to the stomach.

4. 10.2 Bacterial Diseases Affecting the Upper Respiratory Tract Pharyngitis is an inflammation of the throat. S. pyogenes causes streptococcal pharyngitis (strep throat). It enters the upper respiratory tract through respiratory droplets. Some patients with strep throat may develop scarlet fever, exhibiting a rash caused by erythrogenic exotoxins. Figure 05B: Scarlet Fever. © imagebroker/Alamy Images

5. Strep Throat 5

6. Strep throat and scarlet fever can be treated by antibiotics. Acute glomerulonephritus is a rare inflammatory response to M proteins. It may lead to renal damage. Figure 05A: Scarlet Fever. © Medical-on-Line/Alamy Images Scarlet Fever

7. Glomerulonephritis 7 Kidney

8. Glomerular Nephritis from Strep 8

9. Rheumatic Fever 9

10. Rheumatic Fever VideoVideo Rheumatic fever is an inflammatory disease that can develop as a complication of inadequately treated strep throat or scarlet fever. It can affect both the joints and heart. Video It causes permanent heart damage called rheumatic heart disease. 10

11. Rheumatoid Arthritis 11

12. Rheumatic Hear Disease 12

13. Heart Valve Stenosis 13 Video

14. Diphtheria is a life-threatening illness. Diphtheria is a local infection of the throat caused by Corynebacterium diphtheriae. C. diphtheriae bacilli remain in clumps after multiplying, forming a palisade layer. Diphtheria is acquired by respiratory droplet transmission. The bacteria produce an exotoxin that inhibits translation. This results in the accumulation of a pseudomembrane on the tonsils or pharynx.

15. Treatment requires antibiotics and antitoxins. Injection of diphtheria toxoid is used for vaccination. There are usually less than a dozen confirmed cases in the United States each year. The epiglottis is subject to infection, especially in children. Swelling of the epiglottis can block the trachea. FIGURE 10.6: Diphtheria pseudomembrane © Medical-on-Line/Alamy Images Diphtheria video video

16. Diphtheria 16

17. Uvula vs Epiglottus 17

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19. Signs of Strep Throat 19 link

20. Bacterial vs Viral Sore Throat 20

21. Normal vs Strep Throat 21

22. The nose is the most commonly infected part of the upper respiratory tract. Ear infections are common illnesses in early childhood. Figure 07: The Sinuses. Figure 08: Ear Anatomy

23. Acute bacterial meningitis is a rapidly developing inflammation. Bacterial meningitis begins when a localized infection invades the blood and then the meninges around the brain and spinal cord. Figure 09: Pathogenic Steps Leading to Meningitis

24. Neisseria meningitidis causes meningococcal meningitis. Neisseria meningitidis is the major cause of disease and mortality in infants. 90% of the cases occur in Africa’s meningitis belt. Figure 11: African meningitis belt.

25. Other causes of meningitis Streptococcus pneumoniae causes pneumococcal meningitis, about 30% of the cases of meningitis. Haemophilus influenzae Type b (Hib) is mostly prevented now in the US with the Hib vaccine.

26. 10.3 Bacterial Diseases of the Lower Respiratory Tract © NIBSC/Photo Researchers, Inc. FIGURE 10.12: Bordatella pertussis

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29. Tuberculosis Is One of the Greatest Challenges to Global Health. 2 million people die of TB every year, globally. Mycobacterium tuberculosis enters the respiratory tract in small aerosolized droplets. About 90% of people who carry latent tuberculosis will never develop an active infection. They may never even know they are infected. Clinical TB develops within 3 months and can be transmitted to others. VIDEOVIDEO Figure MM07: Mycobacterium tuberculosis

30. Sputum coughed from the lower respiratory tract may contain blood. Macrophages accumulate in the lung. They form a tubercle that harbors M. tuberculosis. If a tubercle breaks apart, bacteria spread throughout the body. FIGURE 14: The progress of tuberculosis

31. Miliary tuberculosis is the development of active tubercles throughout the body. The tuberculin reaction in the Mantoux test can be used for early detection of TB exposure. © James Cavallini/Photo Researchers, Inc. FIGURE 15a: Pulmonary tuberculosis FIGURE 16: Tuberculin Skin Test for Tuberculosis © Bart's Medical Library/Phototake/Alamy Images

32. Tuberculosis Damage to Lungs 32

33. Tuberculosis Symptoms 33

34. Multidrug-resistance Mycobacterium tuberculosis is affecting which antibiotics are used to treat TB. TB is a particularly big problem for AIDS patients. Attenuated M. bovis is used in BCG immunization. © Manfred Kage/Peter Arnold, Inc. FIGURE 15b: Pulmonary tuberculosis

35. Infectious bronchitis is an inflammation of the bronchi. Bronchitis produces excessive mucus and a narrowing of the bronchi. FIGURE 10.17: Bronchus inflammation Adapted from Merck, "Acute Bronchitis: Lung and Airway Disorders", Merck Manual Home Edition, December 09, 2008, http://www.merck.com/m mhe/sec04/ch041/ch041 a.html Bronchitis video video

36. “Typical” Pneumonia Can Be Caused by Several Bacteria. videovideo 80% of “typical” pneumonia cases are caused by Streptococcus pneumoniae. It is acquired through aerosolized droplets or contact. Pneumococcal pneumonia can involve: an entire lung lobe (lobar pneumonia). both lungs (double pneumonia). or patches in the respiratory passageways (bronchopneumonia). Figure 18: Streptococcus pneumoniae. Courtesy of Dr. Mike Miller/CDC

37. Haemophilus influenzae can cause: “typical” pneumonia. otitis media sinusitis. Staphylococcus aureus is a common hospital-acquired form of pneumonia. It may result in necrotizing pneumonia. Klebsiella pneumoniae can be a primary or secondary infection in people with impaired pulmonary function. Figure MM08: Klebsiella pneumoniae

38. Legionella pneumophila causes Legionnaires’ disease. VideoVideo It lives where water collects and becomes airborne in the wind (or ventilation system). Disease develops within a week of inhalation of contaminated droplets. Necrotizing pneumonia may develop. L. pneumophila also causes Pontiac fever, an influenza-like infection. FIGURE 20a: Legionella pneumophila © Collection CNRI/Phototake/Alamy Images

39. Noble Prizes in Microbiology 39