An Indian doctor examines a sex worker who is suffering from TB at a clinic in Calcutta.
FILE PHOTO by Jayanta Shaw
Tuberculosis (TB) is the most common infection in the world, and its on the rise. Two billion people, or one out of every three people on earth, are infected with TB, and it kills 2 million people a year. It is the leading cause of death among HIV-positive people, and the World Health Organisation (WHO) projects that 36 million people could die of the disease over the next 20 years.
WHAT IS TUBERCULOSIS?
TB is an airborne disease that causes coughing, fever, sweating and loss of appetite and weight. TB can attack any part of the body, but it usually attacks the lungs.
WHAT ARE THE SYMPTOMS?
Symptoms depend on where the TB bacteria grow. TB in the lungs may cause a persistent bad cough, pain in the chest or blood or sputum to be coughed up. Other symptoms are weakness, weight loss, chills, fever and night-time sweating.
HOW IS IT SPREAD?
TB is spread through the air from one person to another. Bacteria enter the air when a person with TB of the lungs or throat coughs or sneezes. People nearby may breathe in these bacteria and become infected.
When a person breathes in the bacteria, they can settle in the lungs and grow. The bacteria can move through the blood to other parts of the body, such as the kidney, spine and brain.
TB can be infectious in the lungs or throat. But it is usually not infectious in other parts of the body, such as the kidney or spine.
HOW IS IT TREATED?
The basic treatment regimen takes at least six months to complete and requires as many as four different drugs, which are often unavailable in developing countries.
In 2004 the WHO said three million of the estimated 8.8 million new TB sufferers worldwide received treatment, one million more than in 2002.
WHY IS TB INCREASING?
Population growth, worldwide travel and multi-drug resistant TB have all contributed to an increase in TB. Strains that are resistant to a single anti-TB drug and to a combination of major anti-TB drugs have been found in every country surveyed by WHO. Drug-resistant TB is caused by inconsistent or partial treatment, which threatens TB control efforts.
WHERE IS IT MOST PREVALENT?
According to the WHO, most TB cases occur in South-East Asia, accounting for 33% of the worldwide total. Africa has the next highest number of cases, followed by the western Pacific region.
Individual countries that are particularly hard hit include: India, China, Russia, South Africa and Brazil.
WHAT IS THE CONNECTION TO HIV/AIDS?
HIV/AIDS weakens the immune system, so an HIV-positive person and infected with TB is more likely to succumb to TB than someone infected with TB who is HIV-negative. TB causes eleven percent of AIDS deaths worldwide.
