Date: 3/04/2019 19:29:39
From: mollwollfumble
ID: 1370418
Subject: AIDS home test kit?
On news?
Date: 4/04/2019 03:02:03
From: mollwollfumble
ID: 1370524
Subject: re: AIDS home test kit?
mollwollfumble said:
party_pants said:
Divine Angel said:When I was in high school I wrote a screenplay about a girl who was waiting on HIV results. Back then it took 6 weeks for a result.
Similarly, in an episode of Degrassi High, Spike is looking for a pregnancy test and chooses one which promises results in “only” an hour. These days a pee-on-stick Type only takes a minute or so.
I guess it’s down to better detection, but I don’t know the specifics.
Back in the 90s it was about 2-3 months. A mate of mine got drunk, and went home with an older woman and did unprotected things. He had a long wait to get the all clear.
Is this relevant? These are actually tests for herpes, but would tests for HIV be similar?
J Clin Microbiol. 1992 Feb; 30(2): 522–524.
Comparison of four techniques for detection of antibodies to cytomegalovirus“Four serological methods were compared and evaluated for use in detecting cytomegalovirus antibody in blood and organ donors. Western blotting (immunoblotting), latex agglutination, enzyme-linked immunosorbent assay, and a recent available microparticle enzyme immunosorbent assay were used. … Comparison of the assays showed a moderate number of false-positive results,with a range of 1.1% for the ELISA, 4.4% for the IB, 7.8% for the LA, and 10.0% for the MEIA.”
“Rapid HIV Test. Using technology similar to that of an ELISA … Current HIV antibody tests are often referred to as 2nd generation (detecting IgG antibodies), 3rd generation (detecting both IgM and IgG antibodies), and 4th generation (detecting both HIV antibody and the p24 antigen, which comes directly from the HIV virus).” from http://hivinsite.ucsf.edu/insite?page=basics-01-01
From https://en.wikipedia.org/wiki/ELISA and https://en.wikipedia.org/wiki/Diagnosis_of_HIV/AIDS
3 Types
3.1 Direct ELISA
3.2 Sandwich ELISA
3.3 Competitive ELISA
3.4 Reverse ELISAIn an ELISA test, a person’s serum is diluted 400-fold and applied to a plate to which HIV antigens have been attached. If antibodies to HIV are present in the serum, they may bind to these HIV antigens. The plate is then washed to remove all other components of the serum. A specially prepared “secondary antibody” — an antibody that binds to human antibodies — is then applied to the plate, followed by another wash. This secondary antibody is chemically linked in advance to an enzyme. Thus the plate will contain enzyme in proportion to the amount of secondary antibody bound to the plate. A substrate for the enzyme is applied, and catalysis by the enzyme leads to a change in color or fluorescence.
I’m still not there. Rapid Detection Tests for HIV are specifically referred to as not ELISA in some sources.
Perhaps this is a better guide. http://i-base.info/guides/testing/appendix-3-how-hiv-tests-work
ELISA detection of HIV, wikipedia referred to this as sandwich ELISA.
Rapid tests are a simplified version of antibody ELISA tests. They look for HIV antibodies in the blood. The antigens for HIV are fixed on one particular strip along the rapid test stick. Towards the end of the testing stick are control antigens to show that the test worked.
A sample is placed at the end of the testing stick. A chemical, called a buffer, to facilitate the testing process is added.
The chemical causes the antibodies in the blood to flow along the test stick. When they pass over the section with the antigens, if there are any antibodies for HIV present then they will stick to these antigens and change colour.
Once the test is complete, if there is one stripe it means it is a negative result. If there are two stripes then it means it’s a positive result. If there are no stripes it means the test did not work properly.