What does it mean if I have a positive TB blood test or TB skin test?

A positive TB blood test or TB skin test indicates that you have been exposed to someone with TB. The next step is to have an evaluation for TB symptoms and a chest x-ray. If the symptom review and chest x-ray are negative, you have latent TB infection. With a normal immune system you have a 10% chance of developing TB disease; half of that risk or 5% is within the first 2 years after becoming infected. The other half of the risk is for the rest of your life.


If you are considered to be high risk for developing TB disease, the health department will treat you with a medication that will prevent that from occurring. It is important to understand that if you have latent TB infection (positive TB blood test or TB skin test, normal chest x-ray, no symptoms of TB), you cannot give anyone else TB. You are NOT infectious.


For other services, please call the TB clinic at 602-372-1407 for more information.

Show All Answers

1. What TB services are available at the Maricopa County Department of Public Health clinic?
2. How much does it cost for TB services at Maricopa County Department of Public Health?
3. Do I need an appointment for a TB clearance/Health Card?
4. What does it mean if I have a positive TB blood test or TB skin test?
5. What if I need a TB blood test or TB skin test for work or school, or as a volunteer at a hospital, nursing home, prison, etc.?
6. Why isn't a Health Card free of charge?
7. What if one of my family members is diagnosed with TB?
8. What if I need treatment for latent TB infection?