Tuberculosis

TB AND HIV INFECTION

WHO estimates 11.4 million people worldwide are infected with both M. tuberculosis and HIV (human immunodeficiency virus, which causes AIDS [acquired immunodeficiency disease]). The primary cause of death in those infected with body microbes is from TB, not AIDS. In the United States, health experts estimate about two out of ten people who have TB are also infected with HIV.

In developed countries, such as the United States, many people think tuberculosis (TB) is a disease of the past. TB, however, is still a leading killer of young adults worldwide. Some 2 billion people-one-third of the world's population-are thought to be infected with TB bacteria, Mycobacterium tuberculosis.

TB is a chronic bacterial infection. It is spread through the air and usually infects the lungs, although other organs and parts of the body can be involved as well. Most people who are infected with M. tuberculosis harbor the bacterium without symptoms (have latent TB), but some will develop active TB disease. According to World Health Organization (WHO) estimates, each year, 8 million people worldwide develop active TB and nearly 2 million die.

History of TB
Tuberculosis — a disease also known as consumption, wasting disease, and the white plague — has affected humans for centuries. Until the mid-1800s, people thought that tuberculosis, or TB, was hereditary. They did not realize that it could be spread from person to person through the air. Also, until the 1940s and 1950s, there was no cure for TB. For many people, a diagnosis of TB was a slow death sentence.

What is latent TB infection?

In most people who breathe in TB bacteria and become infected, the body is able to fight the bacteria to stop them from growing. The bacteria become inactive, but they remain alive in the body and can become active later. This is called latent TB infection.

People with latent TB infection

• have no symptoms

• don't feel sick

• can't spread TB to others

Why is TB a problem today?

Starting in the 1940s, scientists discovered the first of several medicines now used to treat TB. As a result, TB slowly began to decrease in the United States. But in the 1970s and early 1980s, the country let its guard down and TB control efforts were neglected. As a result, between 1985 and 1992, the number of TB cases increased. However, with increased funding and attention to the TB problem, we have had a steady decline in the number of persons with TB since 1992. But TB is still a problem; more than 14,000 cases were reported in 2003 in the United States.

What is TB?

Tuberculosis (TB) is a disease caused by bacteria called Mycobacterium tuberculosis. The bacteria usually attack the lungs. But, TB bacteria can attack any part of the body such as the kidney, spine, and brain. If not treated properly, TB disease can be fatal. TB disease was once the leading cause of death in the United States.

TB is spread through the air from one person to another. The bacteria are put into the air when a person with active TB disease of the lungs or throat coughs or sneezes. People nearby may breathe in these bacteria and become infected.