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TB exposure FAQ

TB exposure FAQ

If you are told you have been in contact with someone who has active tuberculosis (TB) disease, you probably have a lot of questions. Below are some of the most common questions we get from people who find out they were around someone with active TB disease.

Active TB disease is caused by germs that infect your body. TB usually infects your lungs but can infect other parts of your body like your brain, kidneys, and liver. TB germs are spread through the air. TB germs are not spread by sharing cups, plates, or eating utensils.

Being a “contact” means you spent enough time with someone who has active TB disease to be exposed. To be exposed, you have to spend a certain amount of time in a certain type of space.. TB is nowhere near as infectious as measles or COVID-19.

A “high-risk contact” is a person who is more likely to become sick with active TB after being in contact with someone who has active TB. Kids under the age of 5 and people with weakened immune systems due to illness (such as HIV) or a medical treatment (such as chemotherapy for cancer) are high risk. Talk to your doctor to find out if you or your family members are high risk.

When someone is diagnosed with active TB disease we talk to them to see who they spent time with and where they went. This is important so we can talk to anyone that may have been exposed to TB and offer testing to see if they have inactive TB. If someone has shared your name with us it is out of love and concern for your health.

If you are a contact of someone with active TB disease, we will reach out to you to offer testing for TB. You may also choose to get tested by your own doctor. If you get tested by your doctor, they may bill your insurance and you may have to pay. If you think you are a contact of someone with active TB disease and you have not heard from us, please call us at 206-744-4579, option 1.

We do two rounds of testing because early detection allows you to start medicine as soon as possible. It can take time for your body to react to TB bacteria so we may recommend you get tested a second time. Testing two times can also help us know if you were infected with TB bacteria recently or in the past.

A doctor may recommend TB medicine for a baby even if their first TB test was negative. TB test results may not be accurate for babies younger than 6 months old, so your doctor may recommend medicine until your baby is 6 months old. When your baby is 6 months old, they may be tested for TB again, and the results will be more accurate. Active TB disease can be life threatening for young children, especially children under 2 years old.

There is no cost fort TB testing and medicine received through the TB Clinic. You may choose to get tested by your own doctor. If your own doctor gives you a TB test, they may bill your insurance and the test may not be free. Unfortunately the TB Clinic is not able to see all people in King County with inactive TB and can only test people who meet the definition of a “contact” of someone with active TB disease. For a list with clinics that provide sliding scale and/or financial help for inactive TB medicine, visit the following: 

You still need a TB test. The TB vaccine (also known as BCG vaccine) can protect against the worst types of childhood TB, but it does not protect against getting infected with TB germs or stopping inactive TB from developing into active TB disease. Getting the TB vaccine (BCG) as a child does not change the results of a blood test but may change the results of a skin test. Many people born outside of the US may have received the TB vaccine in their country of origin.

A positive result on a blood test (called IGRA, QFT, or TSPOT), a normal chest x-ray, and a normal exam done by your doctor means that you have inactive TB (sometimes call latent TB infection or LTBI). If you have inactive TB you don’t have symptoms and aren’t sick. Inactive TB germs live in your lungs and could activate and turn into active TB disease. Once you have active TB disease, you will have symptoms and can spread germs to other people, like family and friends.

Lots of people have inactive TB. Some doctors may not want you to take medicine for inactive TB unless you have certain health conditions that weaken your immune system. Even if you are healthy inactive TB can turn into TB disease.

If you were exposed to someone with active TB disease and became infected with inactive TB, you have a higher chance of inactive TB turning into active TB disease for the next two years. If inactive TB becomes TB disease it can cause a lot of problems. You may have to isolate from family and friends, stay home from work, and take medicine for a long time. Taking medicine for inactive TB decreases your chance of getting active TB disease in the future. This protects you, your family and your friends

If you have symptoms like a cough that won’t go away, you’re coughing up blood, you’re losing weight without trying, have night sweats, are very tired, or have a fever, call your doctor right away. If you don’t have a doctor, you should go to urgent care as soon as you can.