HIV Western blot test
Quick answer: This blood test looks for antibodies to specific HIV proteins to confirm a reactive screening result. Doctors order it as a confirmatory test after a reactive HIV screening test, though many labs now use newer confirmatory methods.
- SampleBlood
- TakesAbout 5 minutes
- Before the testNo special preparation is usually needed.
How the test is done
- 1Staff explain why a confirmatory test is needed
- 2A nurse draws a tube of blood from your arm
- 3The lab separates HIV proteins on a strip
- 4Your serum is checked for antibody bands against each protein
What your results can mean
Reading your report
Results are reported as positive, negative or indeterminate; an indeterminate result needs repeat or further testing with your doctor.
If the result is outside the usual range
A positive result, with a set pattern of bands, confirms HIV antibodies. A negative result after a reactive screen may mean a false screen, and an indeterminate result needs repeat or further testing.
Who usually has this test
People whose HIV screening test was reactive and needs confirmation.
Risks and aftercare
Nothing special for the blood draw; results are discussed privately.
Names and options
Also called: Western blot, HIV confirmatory test
Listed by the hospital as
- WESTERN BLOT TEST FOR HIV
Questions about this test
Why is the Western blot used less now?
Newer confirmatory tests can detect HIV earlier and tell HIV-1 from HIV-2 more reliably. Some labs still use Western blot.
What does an indeterminate Western blot mean?
It means some bands showed but not enough for a clear result. It can happen in very early infection or for other reasons, so the test is repeated or a viral load test is done.
Can pregnancy cause an unclear HIV result?
Pregnancy and some other conditions can occasionally cause non-specific bands. That is why results are always confirmed before a diagnosis.
Related tests
Tamara Hospital & IVF Centre, Rajajinagar
34/3, 10th Cross Road, opp. Vardhaka Sardar Patel School, 1st N Block, 2nd Stage, Rajajinagar, Bengaluru 560010
The hospital is open 24 hours. Call before you come to check the timing for your scan or sample collection.
Get directions ↗IVF Pulse fertility care at Tamara Hospital →
Reception
Waiting area
IVF lab
This page explains each test in general terms so you know what to expect. It is not medical advice: your doctor decides which tests you need and what your results mean. Reference ranges differ between laboratories. Updated 4 November 2026.