UK SMI Title goes here

This reflects the ability of 4th generation HIV assays to detect HIV p24 antigen, whereas third generation HIV assays detect only antibodies (IgM and IgG) against HIV-1 and HIV-2. This antibody response occurs after p24 antigen but, at 12 weeks post-exposure, 99% of all true infections should be picked up by 3rd generation assays. ................
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