Tuberculosis (TB) is a contagious bacterial infection that primarily affects the lungs, but it can also impact other parts of the body, such as the kidneys, spine, and brain. It is caused by the bacterium Mycobacterium tuberculosis and remains one of the world’s most persistent infectious diseases. Despite significant advancements in diagnosis and treatment, TB continues to be a major public health challenge, particularly in developing countries.
The Spread of Tuberculosis
TB is primarily transmitted through airborne particles when an infected person coughs, sneezes, or even talks. People who breathe in these microscopic droplets can become infected. However, not everyone who is exposed to the bacteria develops TB. In fact, many people who are infected with Mycobacterium tuberculosis do not show symptoms, a condition known as latent tuberculosis. Latent TB can become active if the immune system becomes weakened, for example, due to HIV infection or malnutrition.
Symptoms of Tuberculosis
When TB becomes active, it can cause a range of symptoms. The most common symptoms include:
- Persistent cough (lasting more than three weeks)
- Chest pain
- Coughing up blood or sputum
- Fatigue
- Unexplained weight loss
- Night sweats
- Fever and chills
If left untreated, TB can be fatal, but it is treatable with a combination of antibiotics over several months.
Diagnosis and Testing
Diagnosing TB involves several steps, including a thorough medical history and physical examination. The most common test is the tuberculin skin test (TST), where a small amount of TB protein is injected into the skin, and the area is checked for a reaction. A positive test indicates that a person has been exposed to the bacteria, but it does not confirm that they have active TB. Additional tests, such as chest X-rays and sputum analysis, are used to confirm whether the disease is active.
In some cases, a molecular test known as the GeneXpert can detect the presence of TB bacteria and determine if the strain is resistant to common TB drugs, such as rifampicin.
Risk Factors for Tuberculosis
Several factors increase the risk of contracting TB, including:
- HIV/AIDS: HIV weakens the immune system, making it more susceptible to TB.
- Close contact with an infected person: TB is more common in households or environments where people are in close proximity to one another.
- Living in or traveling to high-risk areas: TB is more prevalent in sub-Saharan Africa, India, and Southeast Asia.
- Weakened immune system: Conditions like diabetes, cancer, or organ transplantation, and use of immunosuppressive drugs, increase the risk.
Treatment of Tuberculosis
TB is treatable with antibiotics, but treatment requires a long course of multiple drugs. The standard treatment for TB lasts about six months and includes medications such as isoniazid, rifampicin, pyrazinamide, and ethambutol. It’s essential for patients to complete the entire course of antibiotics to prevent drug resistance. In cases of drug-resistant TB (MDR-TB or XDR-TB), treatment can be more complicated and may require second-line drugs and longer periods of therapy.
Prevention and Global Efforts
Preventing TB involves early diagnosis, proper treatment, and ensuring that those infected with latent TB receive preventive therapy to avoid developing active disease. In addition to these individual measures, there are global health initiatives aimed at reducing the spread of TB, such as the World Health Organization’s (WHO) End TB Strategy, which aims to reduce TB deaths by 90% by 2035.
Vaccination with the BCG vaccine (Bacille Calmette-Guerin) is commonly administered to infants in countries with a high burden of TB. Although the BCG vaccine does not provide complete protection against TB, it can reduce the risk of severe forms of the disease, such as TB meningitis.
Tuberculosis continues to be a global health problem, with millions of new cases and deaths reported annually. However, with early detection, proper treatment, and global efforts aimed at prevention and control, it is possible to reduce the burden of the disease. Raising awareness, improving access to healthcare, and enhancing TB diagnostics and treatments are all essential steps in moving closer to a world free of TB. If you suspect you have TB or have been exposed to the bacteria, seeking medical attention early can ensure timely treatment and prevent the spread of the disease to others.
