Tuberculosis (TB) is a serious infectious bacterial disease, which most commonly affects the lungs. It is mainly transmitted from person to person via droplet nuclei (aerosols) from the lungs of people with active pulmonary disease.
Because there is currently no completely effective vaccine, control of the disease relies heavily on detecting infectious cases and treating them for at least six months with a combination of antibiotics. The aim of treatment is to cure the patient and achieve non-infectiousness, hence interrupting transmission of the disease, while avoiding the emergence of drug resistance.
In the European Union, TB case notification rates are among the lowest in the world. However, the epidemiological pattern varies considerably from country to country, with some countries showing steady progress towards eliminating the disease, while others still face unacceptably high case notification rates. In all countries, control efforts have to deal with the challenges of multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB, co-infection of TB and human immunodeficiency virus (HIV) infection, and the concentration of cases in vulnerable groups.
The most important causative agent of tuberculosis is Mycobacterium tuberculosis. M. tuberculosis, together with M. bovis, M. africanum and M. microti, form the ‘M. tuberculosis complex’, which is a group within the genus Mycobacterium. This genus also includes many different nontuberculous mycobacteria of which M. leprae and M. avium are best known.