Question

Briefly describe the causes, prevention and control of tuberculosis.

Hint:

Adhering strictly to the full course of TB medication is critical. Stopping treatment early when symptoms improve allows the most resilient bacteria to survive, mutate, and cause highly dangerous Multi-Drug Resistant Tuberculosis (MDR-TB).

Answer 1

Step 1: Causative Agent and Pathogenesis:
Tuberculosis (TB) is a chronic, infectious bacterial disease caused by the rod-shaped, acid-fast bacillus Mycobacterium tuberculosis.

• It primarily infects the lungs (pulmonary TB) but can spread through the blood or lymphatic system to any organ, such as the lymph nodes, bones, joints, kidneys, or brain (extra-pulmonary TB).
• Transmission occurs through airborne droplets expelled into the air when a person with active pulmonary TB coughs, sneezes, spits, or speaks.

Step 2: Preventive Strategies:
Preventing the spread and activation of tuberculosis relies on several public health measures:

• Active Immunization: Administering the Bacillus Calmette-Guérin (BCG) vaccine at birth. This vaccine provides strong protection against severe, life-threatening childhood forms of the disease, such as tuberculous meningitis and miliary TB.
• Environmental and Infection Control: Enhancing ventilation and natural sunlight in homes, hospitals, and crowded settings to dilute and destroy airborne bacilli. Encouraging respiratory hygiene, such as covering the mouth and nose when coughing.
• Nutritional Preventive Measures: Maintaining a balanced diet rich in protein, energy, and micronutrients (especially Vitamin A, Vitamin D, and Zinc) to support strong cell-mediated immunity. This helps prevent latent TB infections from reactivating into active, infectious disease.

Step 3: Control Measures:
Controlling tuberculosis at the population level is coordinated through structured public health protocols:

• The DOTS Strategy (Directly Observed Treatment, Short-course): This WHO-recommended system is the cornerstone of TB control. It focuses on:
  • Case detection through reliable sputum smear microscopy.
  • Standardized, multi-drug regimens using first-line anti-TB medications (Isoniazid, Rifampicin, Pyrazinamide, and Ethambutol) for a minimum of 6 months.
  • Direct observation of treatment by a healthcare worker or trained volunteer to ensure patient compliance.
• Contact Tracing and Prophylaxis: Screening close contacts of active TB patients to identify early infections and providing preventive drug therapy (chemoprophylaxis with Isoniazid) to high-risk individuals.