Tuberculosis

Biology: Cambridge International A Level, topic 10.1.2

Tuberculosis (TB)

Tuberculosis is an infectious disease of the lungs, caused by bacteria. Without treatment, it can become very serious and potentially fatal.

Human tuberculosis is caused by Mycobacterium tuberculosis. It infects pulmonary (lung) phagocytes.
Tuberculosis in cattle is caused by Mycobacterium bovis, but this can also affect humans.
TB tends to latently infect individuals, This means individuals are infected but don't show symptoms.
When an individual's immune system is weakened, the TB infection can activate.
The inflammatory response in the lungs can lead to symptoms such as coughing, breathing difficulties, and temperatures.

Tuberculosis can be treated using antibiotics.
Vaccinations, such as the BCG vaccine, are available for some strains of tuberculosis, but not all of these are routine childhood vaccinations in the UK.

Tuberculosis is spread when infected droplets from the lungs are coughed into the air and breathed in by others.
Transmission can be prevented by using tissues when coughing or sneezing and having good handwashing practice.
Tuberculosis occurs all over the world, but is particularly common in developing countries with dense populations.