Molecular screening for HIV-1 group N and simian immunodeficiency virus cpz-like virus infections in Cameroon

On the basis of genetic diversity, HIV-1 has been divided into three groups, M (major), O (outlier) and N (nonM-nonO). HIV-1 group M infections are common worldwide, group O infections are restricted to central Africa, whereas group N infections have only been identified in Cameroon. It was further shown that HIV-1 group N is a mosaic of divergent HIV-1 and simian immunodeficiency virus (SIV)cpz lineages, indicating possible co-infection and recombination in an ancestral chimpanzee host. These data suggest that zoonotic transmission of lentiviruses plays an important role in the emergence of human retroviruses. Given that the conditions favoring human exposure to chimpanzees have increased in Cameroon and other parts of Africa because of commercial logging and hunting practices, it is possible that additional new transmissions of this virus may have occurred. Therefore, more studies are needed to assess the prevalence of HIV-1 group N and SIVcpz viruses to obtain a better understanding of their spread and their continued emergence into the human population.