Abbott's combo assay detects HIV earlier

A new HIV antigen-antibody combination assay can identify infection earlier than a conventional test, according to data from two studies  presented by US health care major Abbott Laboratories at the 16th  Conference on Retroviruses and Opportunistic Infections, held in  Montreal, Canada.

Acute HIV infection, the early phase of infection when symptoms begin to  emerge, cannot be identified by most routinely-used serological tests,  which can detect HIV antibodies from around 22 to 25 days after initial  infection. Abbott's Architect Ag/Ab (antigen/antibody) Combo assay can  also detect HIV antigens, which emerge at a much earlier stage.  Architect is currently available in Europe but not in the USA.

In the EXPLORE study, blood samples were collected every six months from  men who have sex with men (MSM) who were HIV antibody negative at  enrollment. The previous seronegative specimens from patients who  subsequently tested HIV antibody positive were then screened  with  Architect. The Abbott combination assay detected 62% of the acute  infections compared to 14% by a third-generation antibody test.