What is initial testing with interferon gamma release assay (in place of TST)?
A. To fulfill the requirement of the initial TB testing, civil surgeons may, as of November 1, 2009, use interferon gamma release assay (IGRA), which are blood tests. The IGRAs that are currently acceptable to CDC are: the QuantiFERON ® TB Gold Test, the QuantiFERON® TB Gold in Tube Test, and the T-Spot ® TB Test. CDC may add additional tests. If it does, it will publish the inclusion of any test on its website at http://www.cdc.gov/ncidod/dq/civil.htm. If you choose an IGRA (in place of a TST), the civil surgeon will take a blood sample from you during the medical examination. The blood is used to perform the TB initial screening test. Unlike with the TST, you will not have to return to the civil surgeon’s office to have the test result read. The results of the IGRA test are generally available within 24 hours of your office visit. If the result is negative, you will probably not need any further testing for TB. If the result is positive, you will be required to have a chest x-ray as
