Immunologic profile of HIV-2 seropositive African individuals (follow-up).

In the geographic distribution of HIV-2, it is known that this infection is most prevalent in West Africa. Since 1986 we have studied seropositive and seronegative clusters, in Guinea-Bissau with follow-ups in 1988, 1989, 1990 and 1991. Analysis of the results show the high incidence of this infection. 8.51% of the 4,372 people of the general population studied were seropositive, showing the high predominance of HIV-2 infection. Only 4 cases were exclusively reactive to HIV-1 and a slow evolution of HIV-1 infections. In the seroconversions of HIV-2 infections the antibodies appeared first to the core components and secondly to the surface glycoproteins. Some of the laboratory parameters affected in the evolution of the infection include a gradual increase in immunoglobulins and a decrease in CD4 lymphocytes and in the CD4/CD8 ratio. A comparison of these variations in HIV-2 infected people, with or without cross-reactivity to HIV-1, reveals that they are much more evident in exclusively HIV-2 positive people. This fact can indicate that the variants responsible for the cross-reactions are less pathogenic and phylogenetically less developed.