Fact sheet about Tuberculosis

What is Tuberculosis?

TB is an infection or disease caused by a germ that you breathe into your lungs. There are two forms of TB: TB infection and TB disease.

What is TB infection?

TB infection is the form of TB where you have a small number of TB germs remaining alive in your body, but they are not harming you. Your body’s defenses (your immune system) are keeping them from causing problems. You feel fine, you are not sick and you cannot give TB germs to anyone. If you have TB infection and your immune system becomes weak from another disease or from medicines you may take, your TB infection can develop into TB disease. TB infection is sometimes called “latent” or “sleeping” TB.

What is TB disease?

TB disease is the form of TB where you have a large number of TB germs living in your body and the germs are causing harm. Usually you feel sick, and you often can spread TB germs to others. TB disease can be found in any part of your body but it usually affects your lungs. The most common symptoms of TB disease are coughing, fever, loss of appetite, weight loss, weakness, night sweats and feeling very tired.

How do you get TB?

TB germs go into the air when someone who is sick with TB disease in the lungs coughs, sneezes, speaks or sings. People who are living, working or spending a lot of time with this person share the same air. They can breathe in the TB germs and get infected with TB.

You cannot get TB from a person with TB infection.

Can you get TB from sharing food?

No. TB germs are spread from person to person through the air only. You cannot get infected with TB germs by sharing or handling food or other objects.

Who is at risk for getting TB infection?

People at risk for getting TB infection are those who have had contact with a person with TB disease during the time they were coughing TB germs into the air. People who have lived in parts of the world where there is a lot of TB are at risk for having TB infection.

Is there a test for TB infection?

Yes. There are two different types of tests for TB infection, a blood test and a skin test. Either test can find out if you have TB germs in your body. With a blood test, a small amount of your blood is taken for the test. With a skin test, a small amount of fluid is placed under the skin of the forearm. You will need to come back in two or three days to have your doctor or nurse read the skin test results. If your TB test is positive, it means that you have TB germs, and your doctor may order a chest X-ray to be sure you are not sick with TB disease.

Can TB infection be treated?

Yes. Your doctor or nurse may give you one or more medicines to treat TB infection. You will take the medicine for 3 to 9 months, depending on the medicine. It is important to take medicine for TB infection so it doesn’t turn into TB disease.

Can TB disease be treated?

Yes. If you have TB disease, you will take several TB medicines for at least 6 months to cure TB disease.

What is drug resistant TB disease?

Drug resistant TB disease is caused by TB germs that cannot be killed with common medicines. If you have drug resistant TB disease, you may have to take more, and different, TB medicines for at least 12 months. TB can become drug resistant if you do not take your TB medicines according to the directions or if you stop taking the medicines before your treatment is over. You can also become infected with drug resistant TB if the germs you breathed in were from a person with drug resistant TB.

What is BCG?

BCG is a vaccine against TB that is given in countries where TB is common. It can help prevent infants and small children from getting sick with TB disease. At best BCG protects children for up to 5 years, and sometimes it does not protect against TB at all. It is rarely used in the United States.

Can BCG vaccine cause a positive TB test?

BCG does not cause a positive blood test result. A positive TB skin test result is usually from TB germs in your body, not from the BCG vaccine.

More information

For more information about TB, contact your city or town Board of Health or the Massachusetts Department of Public Health, Tuberculosis Program at (617) 983-6970.

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