Tuberculosis (TB) is a contagious infectious disease caused by the bacterium
Mycobacterium tuberculosis. It primarily affects the
lungs but can also impact other parts of the body. TB is one of the top ten causes of death globally, particularly in low- and middle-income countries.
TB is primarily transmitted through the
airborne route. When an infected person coughs, sneezes, or speaks, they release tiny droplets containing the bacteria into the air. Individuals nearby can inhale these droplets and become infected. The risk of transmission increases with prolonged and close contact with someone who has active TB.
The symptoms of TB can vary depending on the part of the body affected. Pulmonary TB, which affects the lungs, typically presents with a
persistent cough lasting more than three weeks, chest pain, and coughing up blood. Other common symptoms include
fever, night sweats, fatigue, and weight loss. Extrapulmonary TB, which affects organs other than the lungs, can cause a variety of symptoms depending on the affected organ.
TB is a major global health concern, with an estimated 10 million new cases and 1.5 million deaths annually. The
World Health Organization (WHO) has identified 30 high-burden countries that account for more than 85% of the world’s TB cases. The
incidence rate of TB is higher in regions with limited access to healthcare, high rates of
HIV infection, and poor socioeconomic conditions.
Drug-resistant TB is also a growing problem, complicating treatment and control efforts.
TB treatment typically involves a
combination of antibiotics taken for six to nine months. The most common first-line drugs are
isoniazid,
rifampin,
ethambutol, and
pyrazinamide. Treatment adherence is crucial to prevent the development of drug-resistant TB. Multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) require longer and more complex treatment regimens.
Prevention strategies include
vaccination with the
BCG vaccine, which provides some protection against severe forms of TB in children. Public health measures such as early detection, treatment of active cases, and
contact tracing are essential to reduce transmission. In high-risk settings,
infection control practices like adequate ventilation, respiratory protection, and isolation of infectious patients are critical.
TB control faces several challenges. The
diagnostic tools available are often inadequate in resource-limited settings, leading to missed or delayed diagnoses. Treatment adherence is another significant issue, as the long duration of therapy can lead to non-compliance. The rise of drug-resistant TB strains complicates treatment and increases healthcare costs. Additionally, TB stigma and lack of awareness hinder effective control measures.
Advancements in
diagnostic technologies,
treatment regimens, and vaccine development are crucial for the future of TB control. Efforts to improve health systems, integrate TB services with other healthcare services, and address the social determinants of health are essential. Global initiatives like the
WHO End TB Strategy aim to reduce TB incidence and mortality by 2035 through coordinated international efforts.
