Health Iowa Q&A

What is Tuberculosis?
Tuberculosis (TB) is a disease caused by bacteria called Mycobacterium tuberculosis. The bacteria usually attack the lungs, but TB can attack any part of the body such as the kidney, spine, and brain. If not treated properly, TB disease can be fatal. It was once the leading cause of death in the United States. You may have heard it referred to as “consumption” many years ago.

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

Not everyone who is infected with TB bacteria becomes sick. People who are not sick but have the bacteria in their body have what is called latent TB infection (LTBI).
People with LTBI do not usually feel sick, do not have symptoms, and cannot spread the disease to others. Some people with LTBI (about 10%) will go on to get TB disease.

People with TB disease can be treated if they seek medical help. Even better, most people with LTBI can take a medication so that they will not develop active TB disease.

Why get tested for TB?
In recent years, TB rates in the USA have been rising particularly in large cities. And anyone who has traveled internationally – especially to certain parts of the world – has potentially been exposed to the TB bacteria. One way of controlling TB is to identify and treat infection before it spreads. The TB screening test is the simplest and most accurate method of identifying persons infected with TB. In individuals, who show a positive TB screening test, a chest X ray is normally required to check for active TB disease.

How can I reduce my chance of getting active TB?
Starting in the 1940s, scientists discovered the first of several medicines now used to treat TB. As a result, TB slowly began to decline 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 resurgence of TB, the U.S. has seen a steady decline in the number of persons with TB since 1992. TB is still a problem; more than 14,000 cases were reported in the U.S. in 2005 (last year for which data is available).

Difference between Latent TB Infection (LTBI) and Active TB Disease

Latent TB Infection
• No symptoms
• Doesn’t feel sick
• Can’t spread the bacteria to others
• Usually has a positive skin test or QuantiFERON-TB® Gold test (Cost is $85*)
• Normal chest x-ray and negative sputum smear
• Needs treatment for latent TB infection to prevent active TB disease
Active TB Disease
Symptoms that may include:
o A bad cough that lasts 3 weeks or longer
o Pain in the chest
o Coughing up blood or sputum
o Weakness or fatigue
o Weight loss
o No appetite
o Chills
o Fever
o Night sweats
• Usually feels sick
• May spread the bacteria to others
• Usually has a positive skin test or QuantiFERON-TB® Gold test (Cost is $85*)
• May have abnormal chest x-ray, or positive sputum smear or culture
• Needs treatment for active TB disease

More information
Students who wish to schedule an appointment for a TB screening test or who have questions about TB can call 319- 335- 8394 to make an appointment with a Student Health Service nurse. Additional information about TB can be found at the Centers for Disease Control and Prevention website or the World Health Organization website.

Gayle Nelson, MS, RNC
Tuberculosis Surveillance Program Coordinator
Student Health Service

Written 10/20/04
Updated 3/12/08

*Price subject to change

Content source: Division of Tuberculosis Elimination National Center for HIV/AIDS, Viral Hepatitis, STD and TB Prevention. 11/16/07