Airborne Diseases

Question 1

What bacterium causes tuberculosis?

Answer 1

Mycobacterium tuberculosis (other species: M. bovis, M. africanum).

Question 2

Describe the chain of infection for TB.

Answer 2

1. Reservoir: Infected humans (active pulmonary TB).
2. Transmission: Inhalation of airborne droplets from coughing/sneezing.
3. Portal of Entry: Respiratory tract.
4. Susceptible Host: Immunocompromised, malnourished, or HIV-positive individuals.

Question 3

List four symptoms of pulmonary tuberculosis.

Answer 3

Persistent cough (>2 weeks), coughing blood, night sweats, weight loss.

Question 4

How is TB treated?

Answer 4

• Antibiotics: Isoniazid, rifampicin, ethambutol, pyrazinamide (6–9 months).
• Complete treatment: Prevents drug resistance.

Question 5

Name three TB prevention strategies.

Answer 5

• BCG vaccine (for children in high-risk areas).
• Infection control: Ventilation, masks, isolation.
• Contact tracing and latent TB treatment.

Question 6

What virus types cause seasonal influenza?

Answer 6

Influenza A, B, and C (A and B cause most human cases).

Question 7

Explain the chain of infection for influenza.

Answer 7

1. Reservoir: Infected humans.
2. Transmission: Airborne droplets or contaminated surfaces.
3. Portal of Entry: Respiratory tract/mucous membranes.
4. Susceptible Host: Elderly, young children, immunocompromised.

Question 8

What are three hallmark symptoms of influenza?

Answer 8

Sudden high fever, body aches, dry cough.

Question 9

What antiviral is used for severe influenza?

Answer 9

Oseltamivir (Tamiflu), most effective if taken within 48 hours of symptom onset.

Question 10

How can influenza outbreaks be prevented?

Answer 10

• Annual vaccination.
• Hand hygiene and respiratory etiquette (cover coughs).
• Environmental disinfection.

Question 11

What virus causes SARS?

Answer 11

SARS coronavirus (SARS-CoV-1 strain, family Coronaviridae).

Question 12

Outline the chain of infection for SARS.

Answer 12

1. Reservoir: Infected humans.
2. Transmission: Airborne droplets or contaminated surfaces.
3. Portal of Entry: Eyes, nose, mouth (via mucous membranes).
4. Susceptible Host: General population; higher risk for immunocompromised.

Question 13

What symptoms distinguish SARS from other respiratory illnesses?

Answer 13

High fever (>38°C), dry cough, shortness of breath, diarrhea.

Question 14

What measures prevent SARS transmission?

Answer 14

• Infection control: Isolation, PPE in healthcare settings.
• Travel restrictions during outbreaks.
• Surveillance and rapid contact tracing.

Question 15

What links TB, influenza, and SARS?

Answer 15

Transmission via airborne droplets, reliance on respiratory hygiene for prevention.

Question 16

Why are these diseases challenging to control?

Answer 16

High transmissibility, need for prolonged treatment (TB), antigenic shifts (influenza), and potential for global spread (SARS).

Question 17

Name one vaccine-preventable airborne disease in this category.

Answer 17

TB (BCG vaccine) and influenza (annual vaccine).