Tuberculosis Testing & Treatment
Tuberculosis Testing & Treatment
See below for answers to common questions about TB.
Tuberculosis Testing and Treatment
The Bell County Public Health District offers Tuberculosis (TB) testing and treatment. Here are some of the most common questions and TB.
Tuberculosis (TB) is a disease caused by germs that are spread from person to person through the air. TB usually affects the lungs, but it can also affect other parts of the body, such as the brain, the kidneys or the spine. A person with TB can die if they do not get treatment.
The general symptoms of TB disease include feelings of sickness or weakness, weight loss, fever, and night sweats. The symptoms of TB disease of the lungs also include coughing, chest pain, and the coughing up of blood. Symptoms of TB disease in other parts of the body depend on the area affected.
TB germs are put into the air when a person with TB disease of the lungs or throat coughs, sneezes, speaks or sings. These germs can stay in the air for several hours, depending on the environment. Persons who breathe in the air containing these TB germs can become infected; this is called TB infection (TBI). If untreated, TB infection can become TB disease.
People with TB disease [CDC] are sick from TB germs that are active, meaning that they are multiplying and destroying tissue in their body. They usually have symptoms of TB disease. People with TB disease of the lungs or throat are capable of spreading germs to others. They are prescribed drugs that can treat TB disease.
A person with TB infection cannot spread germs to other people. You do not need to be tested if you have spent time with someone with TB infection. However, if you have spent time with someone with TB disease or someone with symptoms of TB, you should contact your doctor or the Bell County Public Health District for TB screening recommendations.
Not everyone who is exposed to TB becomes infected with the TB germs. If you believe you have been exposed to TB, you should contact your doctor or the Bell County Public Health District for more information about screening and testing.
The Mantoux tuberculin skin test (TST) [CDC] is performed by injecting a small amount of fluid (called tuberculin) into the skin in the lower part of the arm. A person given the TST must return within 48 to 72 hours to have a trained health care worker look for a reaction on the arm; this must be done in-person.
The TB blood test [CDC], known as the Interferon Gamma Release Assay (IGRA), measures how the patient’s immune system reacts to the germs that cause TB when present. There are currently two Federal Drug Administration (FDA) approved blood tests on the market: the QuantiFERON®–TB Gold In-Tube test (QFT-GIT) and the T-SPOT®.TB test (T-Spot).
Although the tuberculin skin test has been the most common screening method in Texas, many health departments now use the IGRA test as the standard tool. When choosing a skin test or blood test, consideration can be made based on age, health status (see policy TB 1004), BCG status, and other factors of the person needing the test.
A positive TST or IGRA only tells you if you have TB germs in your body. Other tests may be needed to tell if you have TB disease, such as a chest x-ray (CXR) and other laboratory testing of sputum.
In general, there is no risk associated with repeated tuberculin skin test placements. If a person does not return within 48-72 hours for a tuberculin skin test reading, a second test can be placed as soon as possible. There is no contraindication to repeating the TST, unless a previous TST was associated with a severe reaction.
In general, Texas Department of State Health Services does not recommend that low risk individuals be tested for tuberculosis. If a test is needed or recommended, the general public may ask their primary care provider, local clinics, or pharmacies, among other sites. You may also contact Bell County Public Health District for recommendations regarding individual testing needs.
A person with a positive TST or blood test has the TB germ in their body. It does not tell whether or not the person has TB infection or TB disease. Other tests, such as a chest x-ray, symptom screening and a testing of sputum (phlegm), are needed to determine whether the person has TB infection or TB disease.
There is a vaccine for TB, however it is not generally recommended for use in the United States. Bacille Calmette-Guérin, or BCG [CDC], is a vaccine used in many countries with high rates of TB. BCG vaccination does not completely prevent people from getting TB, but it is used to protect infants and young children from serious, life-threatening diseases, specifically military TB and TB meningitis.
The effect of the BCG vaccine [CDC] wanes overtime and may have little to no effect on positive TST results among adults who received the vaccine as a child.
A person with a history of BCG vaccination can be tested and treated for TB infection if they react to the TST. TST reactions [CDC] should be interpreted based on risk stratification regardless of BCG vaccination history. IGRAs use M. tuberculosis specific antigens that do not cross react with BCG, and therefore, do not cause false positive reactions in BCG recipients—this means a blood test, or IGRA, is preferred for BCG vaccinated individuals.
If you have TB infection but not TB disease, your doctor may want you to take a drug to kill the TB germs and prevent you from developing TB disease. The decision about taking treatment for TB infection will be based on your chances of developing TB disease. Some people are more likely than others to develop TB disease once they have TB infection. This includes people with HIV infection, people who were recently exposed to someone with TB disease, and people with certain medical conditions.
DSHS provides TB medications to public health clinics across Texas including the Bell County Public Health District. People who are presumed to have TB may be given treatment while their clinicians perform further testing to confirm or rule out TB disease.