Tuberculosis (TB) is a contagious bacterial infection caused by Mycobacterium tuberculosis. It primarily affects the lungs but can spread to other organs, including the brain, spine, and kidneys. Despite advancements in medicine, TB remains one of the top infectious disease killers worldwide, affecting millions of people each year.
Causes and Transmission
TB spreads through the air when an infected person coughs, sneezes, or speaks. The bacteria can remain suspended in the air for hours, making transmission easy in crowded or poorly ventilated spaces. However, not everyone exposed to M. tuberculosis becomes sick. Some individuals develop latent TB, meaning they carry the bacteria without symptoms or the ability to transmit it. If the immune system weakens, latent TB can become active, leading to illness.
Symptoms and Diagnosis
Active TB disease presents with persistent cough (sometimes with blood), chest pain, fever, night sweats, fatigue, and unintended weight loss. If untreated, it can be fatal. Diagnosis involves multiple tests, including chest X-rays, sputum analysis, and skin or blood tests to detect TB bacteria. Rapid molecular tests have improved early detection, allowing for quicker treatment initiation.
Risk Factors
Several factors increase the risk of developing TB. People with weakened immune systems, such as those with HIV/AIDS, diabetes, or malnutrition, are more vulnerable. Smoking, substance abuse, and living in overcrowded conditions also heighten the risk. TB is prevalent in regions with poor healthcare infrastructure, making early detection and treatment challenging.
Treatment and Drug Resistance
TB is treatable with a standard regimen of antibiotics taken for six months. The most common medications include isoniazid, rifampicin, ethambutol, and pyrazinamide. However, improper use or incomplete treatment can lead to multidrug-resistant TB (MDR-TB), which does not respond to first-line drugs. Extensively drug-resistant TB (XDR-TB) is even more difficult to treat, requiring longer and more complex treatment regimens with second-line antibiotics.
Prevention Strategies
Preventing TB involves a combination of vaccination, early detection, and public health measures. The Bacillus Calmette-Guérin (BCG) vaccine provides some protection, especially in children, but is not fully effective in preventing pulmonary TB in adults. Efforts to reduce transmission include screening high-risk populations, improving ventilation in shared spaces, and promoting adherence to treatment.
Global Impact and Challenges
Despite efforts to control TB, it remains a major health concern, particularly in low- and middle-income countries. Poverty, limited access to healthcare, and lack of awareness contribute to ongoing transmission. Efforts by global health organizations focus on developing better diagnostic tools, new vaccines, and shorter treatment regimens to improve outcomes.
TB elimination requires a multi-faceted approach, including research, healthcare system strengthening, and social support for affected individuals. As drug resistance continues to emerge, innovative treatments and stronger global cooperation are essential to overcoming this ancient but persistent disease.
