TB is NOT spread by:
No. For many, their immune system is able to remove the bacteria, and they do not develop the disease. In other cases, the person’s immune response ”walls off” the bacteria inside the body, causing the bacteria to become dormant. The person does not develop Active TB during this time, and is said to have Latent TB infection (LTBI). The person is well and cannot spread the infection. If treated at this stage, Active TB can usually be prevented.
Active TB develops when the body can no longer keep the bacteria dormant. The bacteria become "active" and cause the person to become ill. This is called TB disease and may occur if LBTI is not fully treated, if a resistant strain of TB has developed, if the individual's immune system becomes weakened (e.g. cancer, HIV, malnutrition, diabetes, aging with subsequent weakening of the immune system, or long-term steroid use. Sometimes it occurs for unknown reasons.
Active TB develops when the body is no longer able to keep the bacteria dormant. In other words the bacteria become "active" and cause the person to become ill. This is called TB disease. It occurs for a variety of reasons such as: if LBTI is not fully treated, or if a resistant strain of TB has developed or if the individual's immune system becomes weakened (like with cancer, HIV, malnutrition, diabetes, or long-term use of steroids). It can also occur with aging and weakening of the immune system, or it may also occur for other, unknown reasons.
Active TB - Symptoms of TB disease depend on where in the body the TB bacteria are growing.
TB disease in the lungs (pulmonary TB) may cause:
Other symptoms of TB disease include:
Skin testing - This test, called a purified protein derivative (PPD) test, involves injecting a solution with a small amount of an inactivated portion of TB bacteria just beneath the surface of the skin, usually on the inside of the forearm. The person returns in 48-72 hours to have the reaction on the arm “read”. Most individuals previously infected with TB develop a red or swollen bump at the injection site. It usually takes 4 to 10 weeks after exposure to a person with Active TB for a PPD to become positive.
Blood tests - This test is known as an interferon gamma release assay (IGRA). Blood tests simplify TB testing, because they do not require a return trip to read the test reaction, and they are not affected by prior immunization with BCG vaccine. Two approved types provide similar results: Quantiferon Test (QFT) and the T-Spot. UHS uses the QFT.
Active TB is diagnosed by further testing of those with a positive test, and/or those with symptoms:
Chest x-ray to determine if a person has signs of past or Active TB.
Sputum evaluation and culture - to grow the bacterium to determine its sensitivities to TB medications. The person is referred to the TB Clinic for this evaluation.
People who think they have tuberculosis should consult a physician.
Students, should call the University Health Services (UHS) Nurse Advice Line at (512) 475-6877 before coming in to UHS if they think they have TB symptoms. The nurse will make arrangements with the student to reduce the risk of exposing others in case they do have TB. Students concerned that they might have TB should not use MyUHS to schedule an appointment.
Faculty and staff who think they may have tuberculosis from an exposure at work should refrain from coming to work and contact the HealthPoint Occupational Health Program (LWC) at (512) 417-4647 for guidance. Workers' Compensation insurance may apply. They can provide referrals for testing and, if indicated, the faculty/staff member may obtain free treatment from the Austin Public Health TB clinic.
Faculty and staff
When UHS becomes aware of a case of Active TB (either diagnosed in UHS or notified by Austin Public Health) we work closely with the Austin Public Health TB clinic to identify campus individuals who are close contacts (see "How is TB transmitted?" above) of the person with TB. Those individuals are contacted by the UHS Chief Medical Officer, informed of their potential exposure, given information about TB, offered testing, and, if necessary, treated.
Using an abundance of caution, UHS may also email students if they were in a class with a person with Active TB, even if they have not been identified as being at high risk for exposure. Emails inform the student of their possible exposure and provide information about TB, and how to get tested if they wish.
Confidentiality laws prohibit UHS from revealing any identifying information about an individual who has or is suspected of having TB.
For more information, go to the U.S. CDC's Tuberculosis page at or go to their FAQs for TB
Does everyone exposed to TB become infected?
Is there a vaccine to prevent a person from getting TB?
A TB vaccine called Bacillus Calmette-Guerin (BCG) is given in many countries to prevent TB. Usually given to infants, it may be re-administered at other times. BCG offers protection against TB in children but typically does not offer protection into adulthood. It is not routinely used to prevent TB in the United States.
What are the symptoms of TB?
Latent TB - The person with LTBI has no symptoms
How is tuberculosis diagnosed?
Latent TB infection (LTBI) can be diagnosed with a skin test or with a blood test:
Who should get tested for TB?
You should get tested for TB if:
What does one do if they think they have symptoms of TB?
How is TB treated?
TB can almost always be treated and cured. It may require up to 9 months of therapy, depending on the medical regimen used. Those with TB disease need to take several different drugs, because multiple medications do a better job of killing all of the bacteria and preventing them from becoming resistant to medicines used to treat TB.
How does one get tested for TB?
Students
What does UHS do if students possibly have been exposed to TB?
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