Protective correlates against HIVs may have evolved in human populations in the areas of historic occurrence of primate-to-man transmissions of SIVs ancestral to HIVs: studies in these populations may provide crucial insights for treatment and prevention of HIV infection

Abstract

Recent findings suggest that Human Immunodeficiency Viruses, HIV-1 and 2, might have been transmitted to humans from particular primate species. It is thought that some Simian Immunodeficiency Viruses (SIVs), from which HIVs presumably originated, existed in their primate hosts for ages. Behavioral characteristics increasing the probability of contact between these primates and humans (such as keeping monkeys for pets, hunting monkeys for food, improper handling of the monkey meat, etc.) documented in some African countries could have facilitated cross-species transmissions (CSTs) of HIVs. As it has been shown, multiple CSTs took place for both HIVs (1 and 2) and then, in a globalizing world, these local events led to the pandemic. Here, it is brought forward that in the regions of epizooty of SIVs closely related to HIVs, some human populations might have had exposure history to these viruses dating back hundreds years. Lacking the important framework for further spread provided by nowadays globalization, these CSTs could have led to isolated local HIV outbreaks limited to particular tribes or groups. The infections could have extinguished some populations while on the other hand provided evolutionary pressure to select for mechanisms protective for HIV infection and/or disease. Thus, here it is hypothesized that in the areas of the habitat of primates infected with SIVs, from which HIVs are thought to be originated, there could be historically exposed populations which might possess biological correlates of protection from HIVs. Current knowledge on the distribution of primates hosting HIV-related SIVs suggests that epidemiological, primatological, anthropological and molecular biological studies in the areas of Cameroon, Gabon, both Congos and Equatorial Guinea (for HIV-1) and Guinea-Bissau, Senegal, Guinea, Ivory Cost, Sierra Leone and Liberia (for HIV-2) could lead to the discoveries of correlates of protection against HIVs. It is also hypothesized that virology studies in the same areas might reveal less virulent and/or infective viruses which could provide insights in the HIV pathogenesis and vaccinology.