About Tuberculosis (TB), MAHECAS UK
Malawi Health Care Support UK
Home Menu What's New? Contact Us Search Links
About Us At Work Events Newsletters About Malawi
UK Registered Charity Number 1057994

Tuberculosis (TB)

Tuberculosis (TB)
TB Bacteria TB Bacteria Tuberculosis, (TB), is caused by several types of bacteria, collectively called the tubercule bacillus. It can spread via the respiratory route, i.e. directly from one person to another via the air. It can also spread via the gastrointestinal route, i.e. from infected fluid discharges.

As such it is common in poor but densely populated regions. (For this reason, some travellers to Malawi are advised not to travel on public transport and to avoid crowded places.) The most common human form of tuberculosis affects the lungs, although there is a form affecting bones and joints.

When infected the bacteria cause the development of tubercules. These are small legions, consisting of a centre of dead cells and tissues and many tubercle bacilli. This centre is surrounded by scavenger cells, (or phagocytic cells). Although microscopic in size, these tubercules are often found in large groups.

In children infection of the lungs often occurs without symptom. A scar is visible on the lungs using X-ray, and life-long immunity remains. In some cases the infection spreads to the bloodstream, which is fatal if untreated.

Where symptoms do develop, they usually include

  • lack of energy, weight loss, persistent cough.
    This is usually the case in young adults, although tuberculosis can strike at any age. These symptoms then get worse over time and are joined by chest pains, fever and sweating. The forming lesions in the lung may spread enough to erode nearby blood vessels. This leads to the patient coughing up blood. As the usable amount of lung tissue decreases toxaemia and exhaustion increase. This eventually causes death through a failure of the ventilation system. Where the infection reaches the bloodstream it can easily spread and affect any of the body's organs.

    The BCG vaccine has been developed to prevent tuberculosis. A weakened form of the bacilli is injected into the skin. This causes a reaction, followed by immunity.

    There are many drugs available to treat tuberculosis. However, strains of the bacterium can become resistant to the drugs. To avoid this dug-combinations are often used. Where unsuccessful, multi-drug resistant forms of the bacterium may develop. Such forms are nearly always fatal, being near impossible to cure.