Identification of a window period for susceptibility to dual infection with two distinct human immunodeficiency virus type 2 isolates in a Macaca nemestrina (pig-tailed macaque) model

The potential to establish dual retroviral infections was investigated in this study. Groups of macaques infected with human immunodeficiency virus type 2 (HIV-2) isolate (either GB122 or CDC77618) were exposed to the other virus at 2, 4, 8, 12, 14, or 72 weeks after primary inoculation. Dual infections were established in macaques simultaneously exposed to both viruses. In other groups, secondary infections were observed only if challenge occurred at early intervals after primary infection but before a full seroconversion. Polymerase chain reaction and virus-isolation data demonstrated that challenges at 8, 12, 14, or 72 weeks after infection with the initial isolate failed to result in a dual infection. Anti-HIV-2 serologic titers, CD4 levels, virus burden, and the ability to superinfect peripheral blood mononuclear cells in vitro were not correlated with susceptibility to or protection from secondary challenges in this investigation. These findings demonstrate a window period for susceptibility to dual infection and indicate that protection from retroviral infection may be achievable.

Optimizing the delivery of HIV counseling and testing services: the Uganda experience using rapid HIV antibody test algorithms

The AIDS Information Center (AIC) was established in Kampala, Uganda in 1990 in response to increasing interest by members of the general public who wished to know their HIV serostatus. By 1996, >300,000 clients had been seen. HIV serologic testing was performed at a central laboratory and results reported back to AIC after 2 weeks. Approximately 25% of clients failed to learn their HIV serostatus as a result of failure to return or late arrival of results. To address these issues, AIC carried out an evaluation of 3 rapid HIV assays, Sero-Strip, SeroCard, and Capillus, against a standard criterion to identify a testing algorithm that could be used as an on-site confirmatory testing strategy. The study was carried out over a period of 5 working days and 325 clients were seen. An algorithm was identified, which gave no indeterminate results with unambiguously positive or negative specimens, which was 100% sensitive and specific, and which could be integrated with minimal disruption into existing counseling procedures. All clients left AIC knowing their HIV serostatus and having spent <2 hours at the Center. The results of this evaluation demonstrate that "same-day" results can be provided in counseling and testing settings without compromising the quality of counseling or the accuracy of HIV testing.