Skip to main content
Immunology Laboratory

Alert Coronavirus / COVID-19

If you have a new continuous cough, a high temperature, or a loss or change to your sense of taste or smell, do not come to our hospitals. Follow the national advice on coronavirus (COVID-19).

Please find information on our services and visiting restrictions in our COVID-19 section.

Please see our latest guidance on face masks.

This site is best viewed with a modern browser. You appear to be using an old version of Internet Explorer.

Quantiferon-TB Gold Plus

Quantiferon is an ELISA based interferon gamma release assay. Whole blood is stimulated overnight with Mycobacteria Tuberculosis (TB) specific antigens, positive control or a nil control. Interferon gamma concentration from the plasma is measured by ELISA.

Purpose of test

This is similar to the TB ELISpot and is particularly suitable for screening large numbers of healthy people in contact tracing or health care worker screening. This test is not suitable for patients on immunosuppressive drugs or have an immunodeficiency e.g. HIV. TB ELISpot should be performed in these circumstances. Quantiferon assay cannot distinguish between latent and active TB infection.

For detailed recommendations please see NICE clinical guideline 117 (CG117), issued March 2011 (

Specimen requirements

Special quantiferon collection tubes are required for this test.

  • Patients' blood should either be collected in Lithium Heparin tubes (x3) or the 4 Quantiferon blood tubes - Negative Control (Grey), TB1 (Green), TB2 (Yellow) and Mitogen (Purple).
  • Each of tube must contain 1ml of blood (Lithium Heparin (3 tubes, 1ml in each) or Quantiferon (4 Tubes, 1ml in each). More or less than 1ml renders the test inaccurate; such samples will not be tested and repeat samples will be requested.
  • The samples must arrive within 16 hours of venepuncture otherwise the test should not be performed.
  • Samples must not be refrigerated.


Price on application

Laboratory turnaround time

10 working days

Laboratory method


Reference range/units


Associated tests


Shipping and storage

See specimen requirements

Further information and contact details

For further information, email

Last reviewed:17 January 2022