TB Transmission and Types: Active TB and Latent TB

Description

Tuberculosis (TB) is a communicable chronic granulomatous disease caused by Mycobacterium tuberculosis. It is an infectious disease that primarily results in mortality worldwide. Although it typically affects the lungs, any organ can be infected. Notably, TB is the leading cause of death in patients with human immunodeficiency virus (HIV) and immunodeficiency syndrome (AIDS). Active TB occurs when the initial immune response is insufficient, leading to bacterial multiplication and clinically active disease. This mainly affects individuals at higher risk, such as those who are immunosuppressed or have diabetes mellitus (DM) (Rijkers, 2019).

When people with TB cough, spit, speak, or sneeze, the infection can spread through the air, particularly in those with active TB in their lungs. However, those with latent TB do not transmit the disease. Active TB is more prevalent among individuals with HIV/AIDS and smokers. The causative agent of TB is Mycobacterium tuberculosis, a small, aerobic, non-motile bacillus. Its high lipid content accounts for many of its unusual clinical characteristics. Unlike other bacteria that replicate rapidly, Mycobacterium tuberculosis has a very slow replication rate of every sixteen to twenty hours (Rijkers, 2019).

The general manifestations associated with TB include fever, chills, night sweats, loss of appetite, weight loss, and fatigue. Nail clubbing can also occur when TB becomes active and affects the lungs, which happens in about ninety percent of cases. Additional signs and symptoms may involve chest pain and a prolonged cough with sputum production. However, approximately twenty-five percent of individuals with TB may not exhibit any signs or symptoms. Occasionally, individuals with TB may cough up small amounts of blood, and in some cases, the infection may lead to complications such as pulmonary artery involvement or a Rasmussen’s aneurysm, resulting in severe bleeding. TB can progress into a chronic illness, causing extensive scarring in the upper lobes of the lungs (Leitch, 2014).