TUBERCULOSIS


AGENT
Mycobacterium tuberculosis

DESCRIPTION
Among infectious diseases, tuberculosis is the leading killer of adults in the world today, and poses a serious challenge to international public health work. Its resurgence alongside the HIV virus has proved a deadly combination. Of the 14 million people globally who were HIV-positive in 1994, some 5.6 million were believed to be infected with TB as well.

TRANSMISSION
Only persons who are actually sick with TB can infect others; it is not spread by insects, blood supplies or water. Like the common cold, and unlike AIDS, the disease is spread through the air and by relatively casual contact. When infectious people cough, sneeze, talk or expectorate, the TB bacilli in their lungs are propelled into the air where they can remain suspended for hours and be inhaled by others.

Left untreated, a person with active TB will typically infect 10 to 15 other people in the span of a single year. However, only 5-10 % of people who are infected with TB actually become sick or infectious themselves.

SYMPTOMS
Fever, tiredness, weight loss, cough, coughing up blood, chest pain.

INCIDENCE AND DISTRIBUTION
Someone in the world is newly infected with TB literally with every tick of the clock -- one person per second.

Fully one third of the world's entire population is now infected with the TB bacillus.

In the next decade it is estimated that 300 million more people will become infected, that 90 million people will develop the disease, and 30 million people will die from it.

The disease is especially devastating in developing countries, where it accounts for more than a quarter of all preventable adult deaths.

Asian countries, with their large cities, extremely high rates of TB bacillus infection and growing spread of HIV virus, currently account for two-thirds of all TB cases.

New outbreaks are occurring in Eastern Europe, where TB deaths are now increasing again after almost 40 years of steady decline.

TREATMENT AND PREVENTION
Long course of anti-TB drugs. There is no cure for some multidrug-resistant strains of TB.

In the case of TB, treatment is also prevention. People who fail to complete treatment regimens or have been improperly treated may remain infectious to other people. These chronic cases often carry bacilli in their lungs that have become resistant to anti-TB drugs, meaning persons whom they infect will have the same drug-resistant strain. When the disease actually develops in such cases, it is much more difficult and expensive to treat than normal TB, and much more likely to be fatal.

For additional information visit the WHO TB site

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