“TB” is the abbreviation for an infection called Tuberculosis. Tuberculosis is a bacterial infection caused by Mycobacterium tuberculosis. Not everyone with TB gets sick. The bacteria can lay dormant and not cause symptoms. This is called Latent TB Infection (LTBI). Treatment at the latent stage decreases the chance of ever developing the disease.
If not treated at the latent stage, it can progress to TB disease. This infection usually attacks the lungs, but it can affect other parts of the body, such as the lymph nodes, spine, brain and kidneys. If not treated, active TB infection can be fatal.
TB is spread through the air. When someone with active TB disease in the lungs or throat speaks or coughs, the bacteria gets into the air and can linger there for several hours afterwards. Someone breathing this air can become infected with TB. People with active TB disease are most likely to spread the infection to people they spend time with every day. It spreads through close, day-to-day, regular contact. Someone is unlikely to get infected after brief exposure.
TB is NOT spread by:
- Surface contact
- Touch (shaking hands)
- Sharing toothbrush, foods or drink
- Sharing clothing, bedding
- Toilet seats
- Close contacts of someone who is known to have active TB disease.
- People from countries that have high rates of TB
- People who work or live in high risk facilities such as hospitals, prisons, nursing homes, homeless shelters.
- People who are homeless, HIV infected or inject drugs into their veins.
After getting exposed to the TB bacteria, a couple of scenarios can happen. Some people may develop active TB soon (within weeks). In others, the bacteria lays dormant. This is the latent phase of infection. There’s a 5-10% chance of developing an active infection without treatment. The highest chance for developing the infection is within the first 1-2 years after getting the bacteria. This chance decreases if you take treatment for Latent Tuberculosis Infection.
The symptoms depend on where in the body the bacteria is growing. If the bacteria infects the lungs, it can cause:
- A bad cough lasting more than 3 weeks
- Cough that brings up blood and/or phlegm
- Fever and chills
- Weight loss
- Night sweats
Seek medical evaluation and immediately contact your primary care provider for guidance. You may contact your local health department
The risk for developing active infection is much higher if someone’s immune system is weak. People at the extremes of age (either very young or very old) often have weak immune systems. Medical conditions that cause a weakened immune system include:
- Drug/substance use
- Organ transplant
- Chronic steroid treatment for conditions such as organ transplant
- Kidney disease
- Certain cancers
- Treatments for autoimmune diseases such as Crohn’s, Lupus, Rheumatoid Arthritis.
See your primary care provider for tuberculosis testing.
You can have a skin test or a blood test. If either is positive, it only tells you if you have the bacteria in your body, but doesn’t tell you if you have latent or active TB.
Further testing with a chest XRAY or a sputum sample may be needed to make the determination.
You most likely have Latent Tuberculosis Infection (LTBI.) A person with LTBI cannot spread TB to others and is not contagious. Only people with active TB disease can spread TB to other people. If you have LTBI you should consider treatment for this to prevent developing active TB disease.
The vaccine against TB is called Bacille Calmette-Guerin (BCG.) It does not always protect against TB. It is not widely used in the U.S. but it is used in many other countries where TB is more common.
Yes. People who have received the BCG vaccine can receive a TB skin test.