Tuberculosis

What is TB?

Tuberculosis is a disease caused by a bacteria. It is spread by an infected person coughing, sneezing, laughing or even talking. One third of the world's population has been exposed to this bacteria and has "latent TB".(In most cases the body is able to fight the bacteria and often walls it off in the lungs where it remains dormant for many years. This is called "latent TB".) However, when the immune system is weak such as in old age or HIV infection, the TB bugs can escape, multiply and cause disease. This can be prevented by giving a course of INH which kills the dormant bacteria.

The lungs are most commonly the site of disease, but TB can affect many places, causing TB meningitis, spinal TB with paralysis, TB of the gut etc. Typical symptoms of TB in the lungs are a cough for many weeks(sometimes coughing up blood), chest pains, night sweats and weight loss.

In healthy people, TB is generally curable by giving a 6 month course of pills. Without treatment, the disease is slowly fatal. People with a weak immune system are not so able to fight the infection even with the help of pills and are far more likely to die, despite treatment.

Half a million people with HIV died of TB during 2008, according to figures released In December 2009 by the World Health Organization, and TB continues to be the major cause of death among people living with HIV globally.

5.7 million people were treated for TB in 2008, with a global success rate of 87%. WHO recommends a national target of at least 85%; 50 countries achieved cure rates at this level, including Tanzania and Kenya, both countries with high burdens of TB/HIV coinfection.

Treatment failure can result in the development of multi-drug resistant TB (MDR). Just under 30,000 cases of MDR TB were reported in 2008, but WHO estimates that no more than 11% of cases of MDR TB were actually detected and notified to national authorities last year.