| Diagnosis of HIV DISEASE-- | | | | or a more specific test like Western Blot is done to |
| What is ELISA test for HIV ?-- | | | | confirm the diagnosis. |
| Whenever any organism enters the body, the | | | | What is Western Blot test? |
| immune system produces antibodies to it. Hence | | | | This is a more specific test for diagnosis of HIV |
| presence of these antibodies is an indirect evidence | | | | infection. It is generally used to confirm a positive |
| of the infection. | | | | ELISA report. |
| ELISA test for HIV is a test that detects the | | | | What is PCR test for HIV ?-- |
| antibodies to HIV. A positive ELISA test is therefore | | | | PCR stands for Polymerase Chain reaction. It is an |
| an indirect evidence of HIV infection. | | | | advanced test that detects HIV even if it is present |
| However the body takes 6 weeks to 3 months to | | | | in the blood in very small quantity. Hence it can |
| produce antibodies. Thus even after infection the | | | | detect the presence of HIV much earlier as |
| test becomes positive only after 6 weeks to 3 | | | | compared to ELISA, thus decreasing the window |
| months. This period is called as the window period. | | | | period considerably. |
| During this period the patient is infective but the test | | | | Similarly testing for p24 antigen is also a test that can |
| is negative. | | | | decrease the window period. |
| Should a single ELISA test positive report be taken | | | | If a p24 test becomes negative after being positive |
| as an evidence of HIV infection ?-- | | | | earlier, does it mean that the person has been cured |
| In case of ELISA positive; either the test is repeated | | | | of HIV infection ? |