Alternate Names : TB, Phthisis
Tuberculosis is an infection caused by a bacteria called Mycobacterium. It can
affect any organ in the body but most commonly affects the lungs.
What is going on in the body?
TB is spread person to person when the bacteria is coughed into the air by one
person and is inhaled by another person. In most people, the immune system,
which is the body's defense against germs and other invaders, is able to
control the infection. In these cases, the infection may cause few or no
symptoms. Children younger than age 4, teenagers, elderly people, and those who
have problems with their immune systems may develop a more severe infection.
Severe infections can occur in every part of the body, including the brain.
Tuberculosis is a common cause of death in the rest of the world, though death
is rare in the US.
What are the causes and risks of the infection?
Exposure to a person with tuberculosis is the cause of the infection. Certain
populations in the US are at a high risk of getting and spreading the
infection. These "high-risk" populations include:
the poor and homeless
those who abuse alcohol or drugs
people with weakened immune systems, such as those with AIDS or cancer
people from less developed countries where tuberculosis is more