Comparison of the sensitivity of four rapid assays for the detection of antibodies to HIV-1/HIV-2 during seroconversion.

OBJECTIVES

To compare the sensitivity of four rapid assays for the detection of antibodies against HIV-1 during early seroconversion.

METHODS

Four rapid assays for the detection of antibodies to HIV-1/HIV-2 (SUDS HIV 1 + 2, TestPack HIV-1/HIV-2, HIV-SPOT and CAPILLUS HIV-1/HIV-2) were evaluated on 38 sera derived from 14 HIV-1 seroconverters, formerly tested with Abbott second- and third-generation HIV-1/HIV-2 enzyme immunoassay (EIA) and Diagnostic Biotechnology HIV blot 2.2. EIA-negative sera had also been investigated by HIV-1 antigen testing and polymerase chain reaction (PCR) analysis detecting HIV-1 proviral DNA.

RESULTS

On 16 sera which were Abbott second-generation EIA negative, the SUDS assay rated highest with six positive results. Four sera were TestPack positive. No specimens in this group were HIV-SPOT positive or CAPILLUS positive. Of the remaining 22 sera (Abbott second- and third-generation EIA positive), all but two were positive in all tests.

CONCLUSIONS

The study revealed differences in the sensitivities of the rapid assays in the early phase of seroconversion. The most sensitive assay, SUDS, was even more sensitive than the Abbott third-generation EIA, while TestPack and the EIA were equally sensitive. Based on these findings, we suggest the inclusion of these assays in the supplemental testing for detection of antibodies to HIV.