Asymptomatic people are infectious. Most HIV infections are transmitted by asymptomatic people. The person can progress to ARC - AIDS related complex. HIV antigen coated onto wells of plate. Patients serum added to the plate If antibodies are present they will stick to HIV antigen on plate.
Excesses is washed away.
Color change indicated presence of antibodies, when reagent added. If positive test results 2 nd Eliza test done, if still positive another test called Western Blot test is done to confirm. It could also mean that you have not yet made enough antibodies to be detected by the test. To make resonably sure you are not infected engage in no risky behavior for 3-6 months and retest. Viral envelope proteins mutate frequently.