Tuberculosis (TB) is caused by a bacterium called Mycobacterium tuberculosis.  The bacteria usually attack the lungs, but can attack any part of the body.

TB is spread through the air from one person to another. TB bacteria are passed through the air when a person with TB disease coughs, speaks, laughs, sings or sneezes. Anyone near a person with TB disease can breathe the bacteria into their lungs and become infected.

Not everyone who gets infected with TB bacteria becomes sick.
There are two TB-related conditions:

Latent TB Infection (LTBI)

• Occurs when a person has been infected with TB bacteria but the bacteria are kept under control by the body's immune system and the bacteria do not multiply.
• The person does not develop any symptoms of TB and cannot pass the TB bacteria on to other people.
• If the person's immune system becomes weakened at any point in their life, the number of TB bacteria in the body could increase and cause TB Disease.

TB Disease

• Occurs when a person has been infected with TB bacteria and the person's immune system cannot control the TB bacteria and the bacteria begin multiplying.
• People with TB Disease require further testing to determine if they are considered to be infectious (can spread the bacteria to other people).
• Typical symptoms include cough, coughing up blood, chest pain, weakness, fatigue, weight loss, lack of appetite, chills, fever and sweating at night.
• If not treated properly, TB disease can cause severe illness and even death.

Two different tests are currently available to test for TB.  Either test can be used for most people at risk, however one test or the other may be preferred in certain situations.

TB Skin Test (PPD)

• The TB Skin Test is a small injection under the skin and requires two visits to a medical clinic which are 2-3 days apart.
• This test is available free at the Union County Division of Public Health for individuals who are suspected of having TB infection and for high risk individuals who need to be screened for TB infection.
• A fee may be charged for low risk individuals without any known exposure who require screening for school or work purposes.

IGRA Blood Test (Quantiferon)

• The IGRA Blood Test is a laboratory test and requires one visit to a medical clinic to draw a sample of blood.
• The test is available at the Union County Division of Public Health.
• A fee will be charged for this test.
• Medicaid and some private insurance companies may cover the cost of this test.

Results

A positive TB Skin Test or a IGRA Blood Test only determines that a person has been infected with TB bacteria.  Neither one can determine if the person has Latent TB Infection (LTBI) or active TB Disease.

If either test is positive for the presence of TB bacteria, additional tests such as a chest x-ray or sputum samples will be needed to determine which type of infection is present.

TB Testing completed at the Union County Division of Public Health cannot be used for immigration purposes.

Individuals needing TB testing for immigration purposes need to contact the US Civil Surgeon.

For more information, visit Designated Civil Surgeons and Immigration Find A Doctor.

Want more information on how many people in North Carolina are infected with TB each year? Visit North Carolina TB Statistics.