Tuberculosis (TB)


What is TB?

TB is caused by a bacterium called Mycobacterium tuberculosis, which can be killed with antibiotics. There are two stages of TB: infection and disease.

What is Latent (sleeping) TB Infection or LTBI?

A person with latent TB infection has been infected with Mycobacterium tuberculosis but his or her immune system (infection fighters) has been able to control it. A person with latent TB is not sick and cannot infect other people. However, people with latent TB can go on to develop active TB at any time and should talk to their healthcare provider about treatment.

What is Active TB?

A person with active TB has been infected with the TB bacteria and his or her immune system is no longer able to control it. He or she may become very sick with the disease and in many parts of the world people die without treatment. The TB bacteria can infect any part of the body and cause disease, but most people who get TB will have it in their lungs. A person with active TB in the lungs or voice box can spread the bacteria to others through the air when he or she coughs, laughs, sneezes, sings or shouts.

Who is at risk for being infected with TB?

Anyone exposed to a person with TB can become infected because it is spread through the air. TB is not easily spread and requires spending long periods of time in a closed space, such as a house with all the windows shut. TB is still common in many parts of the world, and according to the World Health Organization, about one-third of the world's population is infected with the TB bacteria.  (www.who.int/mediacentre/factsheets/fs104/en/index.html)

TB is not common in the United States, Washington State, or Pierce County.

Pierce County residents with the most risk for being exposed to TB are;

  • People who were born in or travel to areas of the world where TB is at constant epidemic "endemic" levels. TB is endemic in Central and South America, Eastern Europe, Africa and Asia. (www.cdc.gov/travel-static/yellowbook/2014/map_3-13.pdf)
  • People who live or work in crowded areas such as shelters, nursing homes, substance abuse  treatment centers or jails. This happens because someone who is sick can spread TB to others in the closed spaces.
  • Healthcare workers.
  • People who live with someone with active TB.

Who is at risk for developing active TB?

Those that are more likely to become sick with TB after they are infected:

  • People with HIV/AIDS.
  • People who have recently been exposed to someone with TB.
  • Children less than 4 years of age.
  • Persons who have weakened immune systems because of diabetes, lung disease, kidney disease, cancer, or organ transplants.
  • Those who are underweight, take medications that lower immune system function or who smoke tobacco.

How do I get tested for TB?

There are two types of tests for TB infection: a skin test, also called a PPD or TST,  and a blood test. There are two brands of blood tests available in the United States: QuantiFERON TB Gold in Tube® (QFT) and T-Spot TB® (T-Spot).

TB Test

What is a TB Skin Test (TST)?

A small amount of protein solution (purified protein derivative) that is similar to TB is injected under the first layer of skin on the inside of the arm. This purified protein derivative cannot give you TB and is not a vaccine. The test must be read from 48-72 hours after application by a qualified medical person.

What is Two Step TB Skin Testing?

If you are going into training for the medical or dental fields, or you are going to work in a medical or dental facility, you will be required to have a two-step TST. The first test is applied and read after 48-72 hours. If this test is negative, another TST is applied one week after the first test was read. If the reading 48-72 hours later is negative or 0 millimeters, you are not currently infected with TB.

What is a TB Blood Test?

The types of TB blood tests currently used in Pierce County are QFT and T-Spot. For this test, you will have blood drawn. It requires only one visit and the results usually are available within one week. 

Where can I get the TST, QFT or T-Spot?

Talk to your healthcare provider about the test. Many clinics and provider offices can do the testing. Call the provider first to see if you need to schedule an appointment and the cost of the test. If you do not have a regular provider, please go to one of the  clinics listed in this link but call first for pricing information.

What if I have been exposed to TB?

If you are concerned that you have been exposed to TB, contact your healthcare provider or Tacoma-Pierce County Health Department.

How do I Know if I have latent or active TB?

Your healthcare provider can apply a TST or draw blood. If either test is positive, you need a chest x-ray and physical examination to make sure you are not sick with TB. Persons with a positive skin or blood test, no TB symptoms and a negative physical examination have TB infection, not TB disease.

People with active TB usually have one or more of these symptoms:

  • Unexplained cough for three or more weeks.
  • Coughing up blood.
  • Fever.
  • Unexplained night sweats.
  • Unexplained fatigue.
  • Unexplained weight loss.

      People may have some or none of these symptoms. Contact your healthcare provider if you develop these symptoms. A chest x-ray and a laboratory test of your sputum (phlegm) can help to diagnose TB of the lungs.

      What if I have been infected with TB?

      If your provider has determined that you are infected with TB, they will talk with you about taking an antibiotic to kill the TB bacteria.

      What if I have TB disease?

      Washington State Law (WAC 246-101) requires that healthcare providers report all cases of suspected or confirmed active TB in Pierce County residents to Tacoma-Pierce County Health Department. Health Department staff work with all patients who have active TB to make sure they get treatment with TB antibiotics to cure the disease.

      Is there a vaccine for TB?

      There is no vaccine for TB in the United States. In countries where TB is endemic, many infants and children receive Bacille Calmette-Guérin (BCG) vaccine. This vaccine works well to prevent infants and children from dying of TB, but it wears off over time and does not protect children or adults from becoming infected with TB.

      Health Department Tuberculosis Program

      Tacoma-Pierce County Health Department partners with other healthcare agencies and providers in Pierce County to provide the following services:

      • Investigate all reports of suspected TB.
      • Make sure that patients with active TB are isolated, treated and cured.
      • Observe active TB patients taking medications daily.
      • Screen people who are exposed to patients with active TB and make sure they get tested and treated as needed.
      • Screen all new refugees for TB and provide treatment for those infected.
      • Screen immigrants at risk for TB to make sure they don't have active TB and help them access treatment as needed.
      • Provide latent TB testing and treatment for uninsured Pierce County residents who are at risk for getting TB.
      • Provide TB education to community members and healthcare workers.
      • Provide medical consultation.