Tuberculosis is an infectious disease caused by the bacteria Mycobacterium tuberculosis.
It can affect people and some animals. In humans it primarily affects the lungs, but can also affect any other organ.
Causes. When someone who has pulmonary or laryngeal tuberculosis talks, coughs or sneezes, they expel the foreign bacteria and it can live in the environment for several hours. If a person breathes air containing the bacilli, he can become infected.
Just by breathing in the TB bacteria, it can enter the body and settle in the lungs.
Treatment. If left untreated, a person with pulmonary TB infects ten to fifteen people per year on average.
Normally, tuberculosis evolves slowly (over months or even years), although it can occur in an acute and severe form in people with low defences, for example, children, the elderly, people carrying the AIDS virus or those with cancer, diabetes, etc.
The disease slowly destroys the diseased organ and, in the case of the lungs, it can form what are known as a “caverns”. Pulmonary tuberculosis spreads through the air.
If a person breathes air containing the bacilli, he can become infected. However, having the infection does not mean having the disease. It may or may not develop. There is no danger of infection when touching the person, using clothing, books or other objects belonging to the person concerned, nor shaking hands, or drinking from the same glass or using the same utensils or the same dishes. It is also very unlikely that a contagion will outdoors.
People with tuberculosis often feel weak or sick, lose weight, have a fever and night sweats. People with a lung disease, may also cough and have chest pain, and may have blood in the cough.
The tuberculin test is a simple way to know if someone has had ever contact with the germ that causes tuberculosis, tubercle bacillus. It determines if the person has "immunological memory".
For more information visit:
Tuberculosis (TB)
http://www.who.int/topics/tuberculosis/en/
Tuberculosis (TB) Disease: Symptoms & Risk Factors
http://www.cdc.gov/Features/TBsymptoms/
Treatment
http://www.cdc.gov/tb/topic/treatment/default.htm
Tuberculosis
http://www.msf.org/diseases/tuberculosis
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