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Tuberculosis is a contagious disease (it is carried in the droplets of mucus and saliva released into the air `droplet infection') caused by the
bacterium Mycobacterium tuberculosis. There are 2 phases of the disease primary infection and active tuberculosis.
Primary Infection with TB:
Can last for several months and may have no symptoms.
The bacterium causes an inflammatory response from the host's immune system and macrophages engulf it. However, the bacterium can
survive inside macrophages the bacteria are taken up by Phagocytosis, but once inside they resist the killing mechanisms used by these cells
(they have thick waxy cell walls which make them difficult to break down).
TB can also suppress T cells which reduces antibody production and attack by killer T cells.
This occurs if the patient's immune system cannot contain the disease when it first arrives in the lungs. With active TB in the lungs the bacteria
multiply rapidly and destroy the lung tissue, creating holes and cavities. The lung damage will eventually kill the sufferer if they are not treated
with an appropriate antibiotic.
Shortness of breath
Loss of appetite and weight loss
Fever and extreme fatigue.
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A person infected with TB will also experience fever and night sweats. Fever causing substances that are released as part of the
inflammatory response affect the hypothalamus and alter the set point for the core body temperature to a higher temperature.
The raised temperature enhances immune function and Phagocytosis. In addition, bacteria and viruses may produce more slowly at the higher