​5 mL plain blood.

This test is carried out only on screened reactive samples. Samples must be submitted by a referring laboratory and accompanied by screening results.

​Refrigerate samples if delay in transporting to laboratory is anticipated. Do not freeze.

​Western Blot

​HIV status confirmed positive if there are:
(a) Any 2 of p24, gp41, gp120/160 (CDC criteria) OR
(b) 2 of 3 env bands with or without gag and/or pol bands (WHO criteria)

Indeterminate result:
Bands are present that do not meet Positive criteria. Patients should be retested by a screening assay 4 weeks to 6 months later, as indicated on the individual test report. Sample should be accompanied by previous test result and laboratory reference number.

Inconclusive result:
Band profile cannot be definitely characterised as positive, negative or indeterminate. Such a report is accompanied by a request for a second blood sample to be sent later.

Negative result:
No viral specific bands.

​1 - 8 days

​Monday and Thursday