Tuberculosis (TB) is an infectious disease. The mycobacterium tuberculosis causes it. This virus is a close relative of leprosy.
Contrary to leprosy and Buruli ulcer, tuberculosis is a deadly disease: once it has broken out, it leads to death in over half of the afflicted persons.
Tuberculosis afflicts mostly the lungs. The infection spreads from person to person. If the virus is expelled with sputum, people in the surroundings can be infected through sneezing and coughing or even merely through speaking.
Beside the lungs, every other organ can be affected by the tuberculosis bacteria, like e.g. kidneys, lymph nodes, bones and joints.There is a danger of infection even in these forms of tuberculosis.
Similarly as in leprosy, a percentage of the infected people can survive well with the disease. There is no outbreak, instead a so-called latent tuberculosis develops.This form of the disease can linger for the entire lifetime, the afflicted person is externally healthy, but carries the germs around in encapsulated form. More than one-third of the world population is infected with tuberculosis in this manner.
Tuberculosis can be found all over the world – in Mumbai in India or Douala in Cameroon just like in Zurich or Bern in Switzerland. However, the disease spreads particularly among persons, whose immune forces are weakened. In poor countries, weakened immune forces are often the result of poverty and the poor living conditions caused by poverty. Undernourishment, lacking hygiene, confined living spaces, lacking health services and HIV/AIDS. Most of the tuberculosis patients, therefore, live in the poor countries of this world. The affected regions are Africa, Southeast Asia, particularly India, the West-Pacific Region and specially China.
The time between infection and outbreak of tuberculosis can last years, same as in the case of leprosy. If the defence system of the infected persons is poor, then the disease appears mostly after one to two months with chronic cough, loss of weight and increasing weakness.
Tuberculosis patients are soon too weak to carry out any work. If they are the providers of a family, the loss of manpower leads to poverty. In this way, the vicious circle is completed: tuberculosis causes poverty and this poverty causes fresh outbreak of the disease.
The treatment of tuberculosis lasts as a rule six to eight months.
If effective drugs are consumed long enough, a cure can be achieved almost in all patients. If the treatment is broken-off too early or left incomplete, there is a threat of grave relapses and death. A further danger of incomplete treatment is the development of tuberculosis germs, which no longer respond to the usual drugs (drug-resistant tuberculosis).
In the year 2007, approx. 5.5 million tuberculosis patients worldwide were registered. At the same time, the number of new afflictions was estimated at about nine million. Only about 60% of persons affected by tuberculosis, find their way to a proper treatment. 85% of these were successfully treated in 2006.
The number of death cases caused by tuberculosis is estimated at 1.8 million people in 2008. Thus tuberculosis rivals malaria in the first place on the list of the deadliest infectious disease on earth.
Most of the tuberculosis patients live in India and China. Almost 2 million new cases are registered there every year, which is a more than a third of all tuberculosis afflictions in the world.
Tuberculosis is, however, predominantly a problem of the countries of Africa, south of the Sahara. There, tuberculosis frequency is the highest worldwide. This is aggravated through the spread of HIV. Up to 800 afflictions per 100,000 persons occur there (in comparison: in Switzerland, about 7 persons per 100,000 are afflicted by it).