Question

1. What are the normal microbiota of the upper and lower respiratory tract?

2. What defenses does the respiratory tract posses to prevent infection?

3. What are properties of mucus that is so effective?

4. How does whopping cough develop?

5. What are the three stages of pertussis? Include symptoms and signs.

6. What populations are at risk for pertussis?

7. What are the complications of pertussis?

8. How does TB develop?

9. What clinical microbiological tests are performed to confirm TB?

10. What is BCG?

11. How does the skin TB test determine TB status?

12. What are the terms MDR- and XDR- TB?

13. How does flu mutate?

14. Why must the vaccine be given every year?

15. What are the symptoms and signs of flu?

16. How is flu confirmed in a patient?

17. What are the possible treatments for an individual infected with flu?

18. What is the pathophysiology of pneumonia?

19. What is the most common cause of community-acquire pneumonia?

20. What are some of the at-risk populations for penumonia infection?

21. What microbes are responsible for pneumonia?

Answer 1

1. Normal Microbiota of the Respiratory System

The nasal passages and sinuses are primarily colonized by members of the Firmicutes, Actinobacteria, and Proteobacteria. The most common bacteria identified include Staphylococcus epidermidis, viridans group streptococci (VGS), Corynebacterium spp.

2. Physical and mechanical barriers

• Hair lining the nose filters and traps some pathogens.
• Mucus coats much of the upper respiratry tract, trapping potential invaders.
• The angle resulting from the junction of the posterior nose to the pharynx causes large particles to impinge on the back of the throat.

3. Mucins give mucus its slippery feel and are very effective at binding together to form gels, which enables mucus to create a strong barrier against microbes and irritants. Mucus performs a number of important functions to keep the body safe from infection.

4. Whooping cough is caused by a type of bacteria called Bordetella pertussis. When an infected person coughs or sneezes, tiny germ-laden droplets are sprayed into the air and breathed into the lungs of anyone who happens to be nearby.

5. Signs & Symptoms

There are three recognized stages of the disease: catarrhal, paroxysmal, and convalescent. The incubation period for Pertussis is 7 to 10 days. During the first or catarrhal stage of the disease, the symptoms are mild and may go unnoticed or be confused with the common cold or influenza.

6. Unprotected young infants are at highest risk of severe pertussis, but older children, adolescents and adults may also contract the disease.

7. Complications

• Pneumonia.
• Hypoxic encephalopathy.
• Otitis media.
• Tuberculosis activation.
• Epistaxis, hemoptysis.
• Hernia.
• Reinduction of paroxysmal coughing with upper respiratory infections.
• Seizures.

8. Tuberculosis is caused by bacteria that spread from person to person through microscopic droplets released into the air. This can happen when someone with the untreated, active form of tuberculosis coughs, speaks, sneezes, spits, laughs or sings. Although tuberculosis is contagious, it's not easy to catch.

9. The Mantoux tuberculin skin test (TST) or the TB blood test can be used to test for M. tuberculosis infection. Additional tests are required to confirm TB disease. The Mantoux tuberculin skin test is performed by injecting a small amount of fluid called tuberculin into the skin in the lower part of the arm.

10. BCG stands for Bacille Calmette Guerin. BCG is a weakened (attenuated) version of a bacteria called Mycobacterium bovis which is closely related to Mycobacterium tuberculosis, the agent responsible for tuberculosis. BCG is also used as an adjuvant to stimulate the immune response and in cancer chemotherapy.

11. Using a small needle, a health care provider injects a liquid (called tuberculin) into the skin of the lower part of the arm. When injected, a small, pale bump will appear.

12. XDR-TB involves resistance to the two most powerful anti-TB drugs, isoniazid and rifampicin, also known as multidrug-resistance (MDR-TB), in addition to resistance to any of the fluoroquinolones (such as levofloxacin or moxifloxacin) and to at least one of the three injectable second-line drugs (amikacin, capreomycin)

13. Antigenic drift

Influenza viruses constantly change through a process called antigenic drift. This is the random accumulation of mutations in the haemagglutinin (HA), and to a lesser extent neuraminidase (NA) genes, recognized by the immune system. It is most pronounced in influenza A viruses.

14. Because flu viruses evolve so quickly, last year's vaccine may not protect you from this year's viruses. New flu vaccines are released every year to keep up with rapidly adapting flu viruses.

15. Symptoms include fever, chills, muscle aches, cough, congestion, runny nose, headaches and fatigue.

16. Your doctor will conduct a physical exam, look for signs and symptoms of influenza, and possibly order a test that detects influenza viruses. During times when influenza is widespread, you may not need to be tested for influenza. Your doctor may diagnose you based on your signs and symptoms.

17. Usually, you'll need nothing more than bed rest and plenty of fluids to treat the flu. But if you have severe infection or are at higher risk for complications, your doctor may prescribe an antiviral medication, such as oseltamivir (Tamiflu), zanamivir (Relenza), peramivir (Rapivab) or baloxavir (Xofluza).

18. Most pneumonia occurs when a breakdown in your body's natural defenses allows germs to invade and multiply within your lungs. To destroy the attacking organisms, white blood cells rapidly accumulate. Along with bacteria and fungi, they fill the air sacs within your lungs (alveoli)

19. Community-acquired pneumonia is defined as pneumonia that is acquired outside the hospital. The most commonly identified pathogens are Streptococcus pneumoniae, Haemophilus influenzae, atypical bacteria (ie, Chlamydia pneumoniae, Mycoplasma pneumoniae, Legionella species), and viruses.

20. Although anyone can get pneumonia, it is more common in certain groups. Children younger than age 2 and people older than age 65 are most likely to develop it. Certain factors can also increase your risk of pneumonia, such as: Having a weakened immune system.

21. methicillin-sensitive Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, and anaerobes.