Impact of extensive HIV-1 variability on molecular diagnosis in the Congo basin.

Background: Previous studies have shown a high HIV-1 genetic variability in the Republic of Congo. This can greatly influence the performance of molecular assays for HIV-1 diagnosis.

Objectives: To define a reliable test for detection of HIV-1 DNA in this area.

HIV serological screening in a population of pregnant women in the Republic of Congo: suitability of different assays.

Different strategies can be applied for the screening of HIV infection, depending on the local seroprevalence. Within a WHO type III strategy, we compared the results of two different second-line methods for HIV screening of a population of pregnant women in the Republic of Congo. Sera from 3614 consecutive pregnant women were tested for HIV with Genescreen Plus Ag/Ab EIA assay; positive specimens were retested with two different second-line methods.