What is Tuberculosis?
Tuberculosis (TB) is a potentially serious infectious disease caused by the bacterium Mycobacterium tuberculosis. It primarily affects the lungs, but it can also impact other parts of the body such as the kidneys, spine, and brain. TB spreads through the air when an infected person coughs or sneezes, releasing bacteria into the air which others may inhale.
How is TB Transmitted?
TB is an airborne disease. It is not spread by sharing utensils or casual contact. When a person with active pulmonary TB coughs, sneezes, or speaks,
droplets containing the bacteria are expelled into the air. Close and prolonged exposure is typically required for transmission to occur, which is why household contacts and healthcare workers are at higher risk.
What are the Symptoms of TB?
The symptoms of active pulmonary TB include a persistent cough that lasts more than three weeks, chest pain, and coughing up blood or sputum. Other symptoms include weight loss, fatigue, fever, night sweats, and loss of appetite. If TB affects other organs, symptoms may vary accordingly, which can make diagnosis more challenging.
How is TB Diagnosed?
TB diagnosis typically involves a combination of medical history, physical examination, and diagnostic tests. The
Mantoux tuberculin skin test and blood tests like the interferon-gamma release assays (IGRAs) are used to detect TB infection. Chest X-rays and sputum tests are crucial for diagnosing active TB disease. Culturing the bacteria from sputum samples remains the gold standard despite being time-consuming.
What is the Treatment for TB?
TB is treatable with a regimen of antibiotics over a period of 6 to 9 months, depending on the individual's response to therapy and the presence of drug-resistant strains. The most common drugs used are
isoniazid, rifampicin, ethambutol, and pyrazinamide. Adherence to the full course of treatment is critical to prevent the development of
drug-resistant TB.
What is Drug-Resistant TB?
Drug-resistant TB occurs when TB bacteria develop resistance to the most effective drugs. This can happen due to incomplete or improper use of antibiotics. Multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) are more difficult and expensive to treat. These forms of TB require second-line drugs, which are less effective and have more side effects.
How Can TB be Prevented?
TB prevention strategies include early detection and treatment of active cases, vaccination with the
BCG vaccine, and proper ventilation in crowded settings. Preventive therapy for latent TB infection in high-risk individuals and the use of personal protective equipment (PPE) in healthcare settings also play significant roles.
What is the Global Impact of TB?
TB is one of the top 10 causes of death worldwide and the leading cause from a single infectious agent, ranking above HIV/AIDS. It disproportionately affects low- and middle-income countries, and the
World Health Organization (WHO) has a goal to end the global TB epidemic by 2030. Efforts include improved diagnostics, treatment, and vaccination strategies.
What are the Challenges in TB Control?
TB control faces numerous challenges, including the rise of drug-resistant strains, the co-infection with
HIV, and inadequate healthcare infrastructure in high-burden areas. Stigma and discrimination against affected individuals also hinder efforts to control the disease. Continuous research and investment are needed to develop new diagnostics, drugs, and vaccines.
