Tuberculosis is an infection caused by the koch bacillus Mycoplasma tuberculosis which attacks the lungs but may involve any other body part, especially bones and brain in case of inadequate containment by the immune system. Various tuberculosis causes exist, among them: weak immune system, poverty, vicious life, no strict hygiene, alcoholism. In 2008, there was an estimated 9.4 million incident cases of tuberculosis and the prevalence of the disease is estimated to be 200 per 100 000 population in the world. In Europe, the number of tuberculosis cases was 322 310 in 2008 and the annual cost is estimated to 2.1 billion euros per year.
Tuberculosis bacteria are transmitted through air from one person to another via small droplets of saliva produced when speaking, coughing, sneezing.
When the inhaled tuberculosis bacteria enter the lungs, they can multiply and cause a local lung infection (pneumonia). In most patients, within weeks from infection, the immune system limits propagation of tuberculosis infection resulting in asymptomatic that may remain in the body for many years. About 5 % of infected persons will develop the disease.