I understand that a 6 month window period is recommended for HIV testing. I realize also that the majority of people will be positive by 3 months from last exposure.Testing at 6 months is almost 100% reliable. Okay, my question is this...how soon after exposure can the antibody test start picking up HIV infection? Is there any percentages to cover the under 3 month period? As an example..although testing negative say at 2 months is a good sign..what percentage could be expected to show infection if infected at 2 months? Do we have any idea? In additition..what is the fastest known sero conversion that you have heard of? Thanks for the posts..very interesting. JC

This field is still collecting data. It is very hard to find these patients and follow them with serial antibody tests. Antibody tests have been reported to be positive within 4 weeks. My guesstimate would be that 80-90% and 95-98% would be antibody positive by 2 and 3 months respectively. MH