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Research article - Peer-reviewed, 2012

Eastern Chimpanzees, but Not Bonobos, Represent a Simian Immunodeficiency Virus Reservoir

Li, Yingying; Ndjango, Jean-Bosco; Learn, Gerald H.; Ramirez, Miguel A.; Keele, Brandon F.; Bibollet-Ruche, Frederic; Liu, Weimin; Easlick, Juliet L.; Decker, Julie M.; Rudicell, Rebecca S.; Bila-Isia, Inogwabini; Ahuka-Mundeke, Steve; Leendertz, Fabian H.; Reynolds, Vernon; Muller, Martin N.; Chancellor, Rebecca L.; Rundus, Aaron S.; Simmons, Nicole; Worobey, Michael; Shaw, George M.;
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Chimpanzees in west central Africa (Pan troglodytes troglodytes) are endemically infected with simian immunodeficiency viruses(SIVcpzPtt) that have crossed the species barrier to humans and gorillas on at least five occasions, generating pandemic and nonpandemic forms of human immunodeficiency virus type 1 (HIV-1) as well as gorilla SIV (SIVgor). Chimpanzees in east Africa (Pan troglodytes schweinfurthii) are also infected with SIVcpz; however, their viruses (SIVcpzPts) have never been found in humans. To examine whether this is due to a paucity of natural infections, we used noninvasive methods to screen wild-living eastern chimpanzees in the Democratic Republic of the Congo (DRC), Uganda, and Rwanda. We also screened bonobos (Pan paniscus) in the DRC, a species not previously tested for SIV in the wild. Fecal samples (n!3,108) were collected at 50 field sites, tested for species and subspecies origin, and screened for SIVcpz antibodies and nucleic acids. Of 2,565 samples from eastern chimpanzees, 323 were antibody positive and 92 contained viral RNA. The antibody-positive samples represented 76 individuals from 19 field sites, all sampled north of the Congo River in an area spanning 250,000 km2. In this region, SIVcpzPts was common and widespread, with seven field sites exhibiting infection rates of 30% or greater. The overall prevalence of SIVcpzPts infection was 13.4% (95% confidence interval, 10.7% to 16.5%). In contrast, none of the 543 bonobo samples from six sites was antibody positive. All newly identified SIVcpzPts strains clustered in strict accordance to their subspecies origin; however, they exhibited considerable genetic diversity, especially in protein domains known to be under strong host selection pressure. Thus, the absence of SIVcpzPts zoonoses cannot be explained by an insufficient primate reservoir. Instead, greater adaptive hurdles may have prevented the successful colonization of humans by P. t. schweinfurthii viruses.


Bonobons; simian immunodeficiency; Chimpanzees; West central Africa

Published in

Journal of Virology

2012, volume: 86, number: 19, pages: 10776-10791

Authors' information

Li, Yingying
University of Pennsylvania
Ndjango, Jean-Bosco
University of Kisangani
Learn, Gerald H.
University of Pennsylvania
Ramirez, Miguel A.
University of Pennsylvania
Keele, Brandon F.
National Cancer Institute-Frederick
Bibollet-Ruche, Frederic
University of Pennsylvania
Liu, Weimin
University of Pennsylvania
Easlick, Juliet L.
University of Alabama (UA)
Decker, Julie M.
University of Alabama (UA)
Rudicell, Rebecca S.
University of Alabama (UA)
Bila-Isia, Inogwabini (Bila-Isia, Inogwabini)
Swedish University of Agricultural Sciences, Department of Aquatic Sciences and Assessment
Ahuka-Mundeke, Steve
Institut National de Recherche Biomedicales
Leendertz, Fabian H.
Robert Koch-Institute
Reynolds, Vernon
University of Oxford
Muller, Martin N.
University of New Mexico
Chancellor, Rebecca L.
West Chester University
Rundus, Aaron S.
West Chester University
Simmons, Nicole
Makerere University
Worobey, Michael
University of Arizona
Shaw, George M.
University of Pennsylvania
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Sustainable Development Goals

SDG3 Good health and wellbeing

UKÄ Subject classification

Microbiology in the medical area

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