HIV Test

1. Objective:

The objective of the HIV test was to detect antibodies, antigens, or nucleic acids of the Human Immunodeficiency Virus in order to diagnose HIV infection and monitor its stage.

2. Principle:

The principle of HIV testing varied depending on the method:

ELISA (Enzyme-Linked Immunosorbent Assay): It was based on the antigen-antibody reaction where HIV antigens coated on a microplate captured patient antibodies (if present), and a color change indicated positivity.

Rapid Test (ICT – Immunochromatographic Test): It relied on antigen-antibody binding producing a visible colored line on a strip.

Western Blot: It detected specific HIV proteins using patient antibodies as confirmation.

PCR (Polymerase Chain Reaction): It detected HIV RNA/DNA in blood, useful in early infection or newborns.

3. Materials:

Patient’s serum or plasma sample

HIV test kit (ELISA plate / Rapid strip / PCR reagents)

Micropipettes and tips

Buffer solution

ELISA reader (for ELISA method)

Controls (positive and negative)

Personal protective equipment (gloves, mask, lab coat)

4. Procedure (Microscopic/ELISA method):

The microplate wells were coated with HIV antigens.

Patient serum was added into the wells and incubated.

If anti-HIV antibodies were present, they bound to the antigens.

After washing, enzyme-labeled secondary antibodies were added.

Substrate solution was added, producing a color reaction if antibodies were present.

The intensity of color was measured using an ELISA reader at 450 nm.

5. Result:

A positive test showed color development (ELISA) or a visible line on the test strip (Rapid test).

A negative test showed no color reaction or absence of a line.

Borderline or indeterminate results required repeat testing or confirmation with Western Blot/PCR.

6. Uses:

It was used for diagnosis of HIV infection.

It helped in screening blood donors.

It was essential in antenatal screening to prevent mother-to-child transmission.

It was used for monitoring treatment response in HIV-positive patients.

7. Consultation:

A positive HIV test required confirmation with a second test (such as Western Blot or PCR). Patients were advised counseling regarding the implications of the result, disease management, and preventive measures. If confirmed positive, referral to an HIV specialist for antiretroviral therapy (ART) initiation and monitoring was recommended. Confidentiality was strictly maintained.