Tuberculosis (TB) is an infectious disease that primarily affects the lungs, though it can impact other parts of the body. Historically, it has been known by various names such as consumption or the “White Plague,” and it has impacted humanity for millennia. It became particularly widespread during the 18th and 19th centuries, especially in urban areas, leading to significant mortality rates. Despite advancements, TB remains a global health concern, with millions falling ill each year.
Understanding Tuberculosis
Tuberculosis is caused by a specific type of bacteria called Mycobacterium tuberculosis. While these bacteria most frequently target the lungs, they can also spread to other areas of the body, including the gastrointestinal tract, bones, joints, nervous system, lymph nodes, and skin.
There are two main forms of TB: latent TB infection and active TB disease. In latent TB infection, the bacteria are present but remain inactive, causing no symptoms and preventing transmission to others.
A small percentage of individuals with latent TB, 5-15%, will eventually develop active TB disease. This occurs when the bacteria begin to multiply, leading to noticeable symptoms and the potential for the disease to spread. Factors such as a weakened immune system can increase the risk of latent TB progressing to active disease.
Mucus in Tuberculosis Symptoms and Transmission
A characteristic symptom of active lung TB is a persistent cough, which often produces sputum, a mixture of mucus and phlegm. This sputum can appear thick and discolored, sometimes containing streaks of blood. The cough can be mild for several months, which can delay diagnosis and lead to further transmission.
When an individual with active lung TB coughs, sneezes, or speaks, tiny droplets containing bacteria are propelled into the air. These airborne particles can then be inhaled by others, facilitating the spread of Mycobacterium tuberculosis. A person only needs to inhale a small number of these germs to become infected.
The respiratory tract’s mucus lining plays a role in the disease process, as it is where the bacteria can reside and multiply, eventually leading to the production of infected sputum. Without effective treatment, an individual with active TB can infect approximately 10 to 15 other people through close contact over a year.
Identifying Tuberculosis
Diagnosing tuberculosis involves several methods, with sputum samples playing a significant role. One common diagnostic approach is the microscopic examination of sputum for acid-fast bacilli (AFB) smear, which helps identify Mycobacterium tuberculosis. This is often followed by culture tests, where sputum samples are grown in a laboratory to confirm the bacteria and to test for drug susceptibility.
Other diagnostic tools are used to detect TB infection or active disease. Chest X-rays can reveal characteristic changes in the lungs that suggest TB. Tuberculin skin tests (TST) and blood tests, such as interferon-gamma release assays (IGRAs), are also employed to detect TB infection.
These tests are often used in combination. For instance, a positive skin or blood test might indicate an infection, but a chest X-ray and sputum analysis are needed to confirm active TB disease. Rapid molecular diagnostic tests are also recommended as initial tests for individuals showing signs and symptoms of TB.
Treating Tuberculosis
Tuberculosis is a curable disease, but effective treatment requires a sustained course of multiple antibiotics. The standard treatment regimen lasts for an extended period, typically six to nine months. This prolonged duration is necessary to eliminate the Mycobacterium tuberculosis bacteria completely from the body.
Completing the entire course of prescribed medication is important for successful treatment and to prevent the development of drug-resistant TB. Incomplete or inconsistent treatment can lead to the bacteria becoming resistant to antibiotics, making the disease much harder to treat and potentially leading to a recurrence. Public health efforts emphasize the importance of treatment adherence to curb the spread of drug-resistant strains and ensure better outcomes for individuals with TB.