Antibody/Antigen tests?

Hi
Are Ab tests reliable or only P24/PCR is reliable? Can someone throw some light on when and why there are three or more tests. All these while I have been thinking Antibody screening should be enough. Now, I read in a reply from one of the doctors that there chances of late/non-sero conversion.

Kindly explain about the possibility of a normal individual never producing antibodies and has only antigen in him/her. If there exceptions to such a possibility?

Thanks

[godsaveme1]

Jus wanna bump into this post once again requesting expert opinion. Hopin to hear back

[Teak]

http://www.medhelp.org/posts/HIV-Prevention/Help-PleaseHumble-request/show/1826344#post_8427061

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