Tuberculosis is spread through the air when a person who is ill with Active TB of the lungs coughs, sneezes, speaks or sings. The bacteria in these respiratory droplets can then be inhaled by others. It usually takes being in close proximity to a person with Active TB for prolonged periods of time in an enclosed environment to be at a higher risk for infection. In fact, TB is not as contagious as influenza.
TB is NOT spread by:
- shaking someone's hand
- sharing food or drink
- touching bed linens or toilet seats
- sharing toothbrushes
Does everyone exposed to TB become infected?
No, not everyone who is exposed to Active TB develops it. For many, their immune system is able to remove the bacteria and he/she does not develop the disease.
In other cases, the person develops an immune response that controls the bacteria by "walling it off" inside the body. This causes the bacteria to become dormant or asleep. The person does not develop Active TB or become ill at this time, but is said to have Latent TB infection (LTBI). During this stage the person is well and cannot spread the infection to others. If the person is treated at this stage, Active TB can usually be prevented.
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.
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 infection with TB. It usually is given to infants, although it may be given again at other times. BCG offers protection against TB in children, but typically does not offer ongoing protection into adulthood. BCG is not routinely used to prevent TB in the United States. Research shows that this vaccine does not cause a positive skin test.
What are the symptoms of TB?
Latent TB - The person with LTBI has no symptoms
Active TB - Symptoms of TB disease depend on where in the body the TB bacteria are growing.
TB disease in the lungs may cause symptoms such as:
Other symptoms of TB disease include:
- A bad cough that lasts 3 weeks or longer
- Coughing up blood or sputum (phlegm from deep inside the lungs)
- Weakness or fatigue
- Unexplained weight loss
- No appetite
- Fever and chills
- Night sweats
How is tuberculosis diagnosed?
Latent TB infection (LTBI) can be diagnosed with a skin test or with a blood test:
Skin testing - For many years the only TB test available was the TB skin test (TST) which is also called a purified protein derivative (PPD) test. It is performed by injecting a solution with a small amount of an inactivated portion of the TB bacteria just beneath the surface of the skin, usually on 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 skin reaction (a red or swollen bump). In a person who is newly infected, the skin test usually becomes positive within 4 to 10 weeks after exposure to a person with Active TB.
Blood tests - Blood tests, known as interferon gamma release assays (IGRAs), are now available in most areas. Blood tests simplify TB testing because they do not require the person to make a return trip to read the test reaction, and they are not affected by prior immunization with BCG vaccine. Currently there are two approved types that 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 is done to determine if person has signs of Active TB, either currently or in the past.
Sputum evaluation and culture - to grow the bacterium and determine its sensitivities to TB medications. The person will be referred to the TB Clinic for this evaluation.
Should I get tested for TB?
You should get tested for TB if:
- You've been contacted by a health authority (e.g. University Health Services, HealthPoint Occupational Health Program, or Austin/Travis County Health and Human Services Department) letting you know that you've possibly been exposed to somebody with TB; or
- You have spent prolonged periods of time in close proximity within a closed environment with a person known or suspected to have TB disease; or
- You have HIV infection or another condition that weakens your immune system and puts you at high risk for TB disease; or
- You are from (or spent an extended period in) a country where TB disease is very common (most countries in Latin America and the Caribbean, Africa, Asia, Eastern Europe, and Russia); or
- You live somewhere in the United States where TB disease is more common such as a homeless shelter, migrant farm camp, prison or jail, and some nursing homes; or
- You inject illegal drugs; or
- You have symptoms of TB disease.
What do I do if I think I have symptoms of TB?
If you think you have tuberculosis, you need to consult a physician.
Students, please call the University Health Services (UHS) 24-hour Nurse Advice Line at (512)475-6877 if you think you have TB symptoms and before you come in to UHS. The nurse will make arrangements regarding when and where you should check in to reduce the risk of your exposing other UHS patients in case you do have TB. Please don't schedule an appointment using the UHS online scheduling system.
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 clinic at (512)417-4647 for guidance. Workers' Compensation insurance may apply. You will be referred for testing and, if indicated, you may obtain treatment from the Austin/Travis County Health and Human Services Department TB clinic. Treatment for Active TB is provided free of charge through the Austin/Travis County TB Clinic.
How is TB treated?
There is good news for people with TB. It can almost always be treated and cured with medicine, but it requires up to 9 months of therapy, depending on the regimen used. If you have TB disease, you will need to take several different medicines. This is because there are many TB bacteria to be killed and taking several medicines will do a better job of killing all of the bacteria and preventing them from becoming resistant to medicines used to treat the disease.
How do I get tested for TB?
- If you have been contacted by UHS as a possible contact of a person with Active TB, please follow the instructions provided to you in the email.
- If you think you might have been exposed to a person with Active TB, but have not been contacted by either UHS or the ATCHHSD as a possible contact, you should first call the 24-hour Nurse Advice Line.
- If you are needing testing as part of an admissions requirement to The University of Texas at Austin - go to www.healthyhorns.utexas.edu and click "Incoming Students" for information regarding International Student Clinics at the beginning of each semester
- If you need TB testing for professional schools, volunteer work, travel, etc. you will usually get a TB skin test, which is also available at UHS. You can schedule an appointment in the Allergy/Immunization Clinic to have this done by calling (512)475-8301.
Faculty and staff
- If you have been in close contact with someone on campus with TB or suspected of having TB, the Austin/Travis County Health and Human Services Department TB Clinic or HealthPoint may be in contact with you to determine your testing needs.
- If you are concerned about having been exposed to TB in the work place, contact the HealthPoint Occupational Health Program (OHP) at (512)471-4647. OHP can make arrangements for TB screening using a blood test with St. David's Occupational Health at no cost to you.
- Employees needing TB testing related to their job assignment or research work will usually get a TB skin test, which is also available in OHP.
- If you are not a close contact but are still interested in TB screening, you may contact your personal physician for this service or schedule an appointment for testing with the Austin/Travis County TB Clinic by calling (512)972-5460.
What does UHS do if students possibly have been exposed to TB?
When UHS becomes aware of a case of Active TB (either diagnosed in our clinic or notified by the Austin/Travis County Health and Human Services Division (ATCHHSD), we work closely with the ATCHHSD TB clinic to identify campus individuals who are close contacts (see "How Do You Get TB?" above) of the person with TB. Those individuals are contacted by the UHS Medical Director if they are students, informed of their potential exposure, given information about TB, offered testing and, if necessary, treated.
Using an abundance of caution, UHS may also contact students by email if they were in class with the person with Active TB even if they have not been identified as a person at high risk for exposure. These communications let the student know of their possible exposure, provide information about the disease, and give information about how to be tested if they wish. Due to confidentiality laws, UHS cannot reveal the name or other identifying information about an individual who may be the source of tuberculosis or suspected tuberculosis.
For more information on tuberculosis, go to the U.S. CDC's Tuberculosis page at or go to their FAQs for TB.