MODULE 8 INFECTIOUS DISEASE PART 1

Question 1

Which 3 infectious disease are responsible for approximately half of all deaths worldwide?

Answer 1

Lower Respiratory Infections (Infectious): This category includes pneumonia, bronchitis, and other infections affecting the lower respiratory tract, often caused by bacteria or viruses.

Diarrheal Diseases (Infectious): Primarily caused by bacterial, viral, or parasitic infections, diarrheal diseases are a significant global health concern, especially in developing regions.

HIV/AIDS (Infectious): Human Immunodeficiency Virus (HIV) and Acquired Immunodeficiency Syndrome (AIDS) continue to be major contributors to global mortality, particularly in sub-Saharan Africa and other regions heavily affected by the epidemic.

Question 2

Explain why antibiotics are ineffective against viral diseases

Answer 2

Antibiotics target bacteria, not viruses. Viruses lack the cellular structures and processes that antibiotics typically interfere with. Antibiotics are designed to disrupt bacterial cell walls or metabolic pathways, which viruses do not possess.

Question 3

Define the following stages of an infectious disease
- Latent period
- Incubation period
- Communicability period
- Disease period

Answer 3

Latent Period: Time between exposure to the infectious agent and the first appearance of symptoms or signs.

Incubation Period: Time between exposure to the infectious agent and the onset of symptoms.

Communicability Period: Time during which an infected individual can transmit the infectious agent to others.

Disease Period: Time when the individual experiences clinical manifestations of the disease.

Question 4

Which common infectious disease has been responsible for several devastating pandemics?

Answer 4

Influenza

Question 5

Describe the clinical presentation of influenza and how it may become life threatening in vulnerable populations.

Answer 5

Fever
Cough
Sore throat
Muscle aches
Fatigue

In vulnerable populations, such as the elderly, very young, or immunocompromised individuals, influenza can lead to severe complications like pneumonia, respiratory failure, and death.

Question 6

How does HIV virus cause AIDS and what are the risk factors?

Answer 6

HIV attacks the immune system, particularly CD4 cells (T cells), weakening the body’s ability to fight off infections and diseases. When the immune system is severely damaged, and CD4 count drops below a certain level, HIV infection progresses to AIDS.

Risk Factors: Unprotected sex, sharing needles, receiving contaminated blood products, and from mother to child during childbirth or breastfeeding.

Question 7

Differentiate between hepatitis A, B & C and their clinical course.

Answer 7

Hepatitis A: Typically a short-term infection, transmitted through contaminated food or water.

Hepatitis B: Can be acute or chronic, transmitted through contact with infected blood or body fluids.

Hepatitis C: Often becomes chronic, transmitted through contact with infected blood.

Question 8

Describe the difference between primary and secondary infection with tuberculosis

Answer 8

Primary Infection: Initial infection with Mycobacterium tuberculosis. The immune system may control the infection, but bacteria can remain dormant.

Secondary Infection (Reactivation): Occurs when dormant bacteria become active, leading to the development of clinical symptoms.

Question 9

What percentage of the world population have tuberculosis?

Answer 9

Approximately 1/4 of the world’s population is estimated to have latent tuberculosis infection.