Testing for Tuberculosis

TB Testing Graphics_HouseTB Testing Graphics_GlobeTB Testing Graphics_Clipboard
People living with a person with active TB diseasePeople who were born or travel to a country where TB is commonPeople who have pre-existing health conditions


You should consider testing for TB if you:

  • Have been in close contact with someone who has an active case of TB
  • Work in healthcare or an occupation that brings you in close contact with people who may have active TB
  • Lived or used to live in large group settings such as homeless shelters or correctional facilities
  • Have a disease or condition that weakens your immune system, such as HIV/AIDS
  • Have spent an extended period of time in countries outside the United States or Canada, where TB may be more common

If you need a TB test for employment or school, please contact your medical care provider. The Snohomish County Health Department does not provide TB testing services.

Please consider contacting the following for TB testing services related to employment or school:


skin test (tst or ppd)

TB testing is often required for work and school as well as immigration to the United States. A TB skin test takes only a few minutes to administer, but you must return between 48-72 hours to have the test site evaluated for results by a medical professional.

BLOOD TEST (QFT or t-spot) 

Another option for TB testing is a blood test. This only requires one visit and results are available in approximately 3-5 business days.  

positive result 

A positive TB skin test means that you may have been exposed to TB bacteria and have TB infection.  

We recommend that you see your medical care provider following a positive TB test for further evaluation. Your visit may include a chest x-ray and sputum sample collection. 

This evaluation will help further determine if you have inactive TB infection or active TB disease and what type of treatment would be needed.