UMR 145, Institute of Research and Development and University of Montpellier 1, 911 Avenue Agropolis, BP 64501, 34394 Montpellier Cedex 5, France.
J Virol. 2010 Feb;84(3):1464-76. doi: 10.1128/JVI.02129-09. Epub 2009 Nov 11.
Chimpanzees and gorillas are the only nonhuman primates known to harbor viruses closely related to HIV-1. Phylogenetic analyses showed that gorillas acquired the simian immunodeficiency virus SIVgor from chimpanzees, and viruses from the SIVcpz/SIVgor lineage have been transmitted to humans on at least four occasions, leading to HIV-1 groups M, N, O, and P. To determine the geographic distribution, prevalence, and species association of SIVgor, we conducted a comprehensive molecular epidemiological survey of wild gorillas in Central Africa. Gorilla fecal samples were collected in the range of western lowland gorillas (n = 2,367) and eastern Grauer gorillas (n = 183) and tested for SIVgor antibodies and nucleic acids. SIVgor antibody-positive samples were identified at 2 sites in Cameroon, with no evidence of infection at 19 other sites, including 3 in the range of the Eastern gorillas. In Cameroon, based on DNA and microsatellite analyses of a subset of samples, we estimated the prevalence of SIVgor to be 1.6% (range, 0% to 4.6%), which is significantly lower than the prevalence of SIVcpzPtt in chimpanzees (5.9%; range, 0% to 32%). All newly identified SIVgor strains formed a monophyletic lineage within the SIVcpz radiation, closely related to HIV-1 groups O and P, and clustered according to their field site of origin. At one site, there was evidence for intergroup transmission and a high intragroup prevalence. These isolated hot spots of SIVgor-infected gorilla communities could serve as a source for human infection. The overall low prevalence and sporadic distribution of SIVgor could suggest a decline of SIVgor in wild populations, but it cannot be excluded that SIVgor is still more prevalent in other parts of the geographical range of gorillas.
黑猩猩和大猩猩是已知唯一携带与 HIV-1 密切相关病毒的非人类灵长类动物。系统发育分析表明，大猩猩从黑猩猩中获得了猿猴免疫缺陷病毒 SIVgor，而来自 SIVcpz/SIVgor 谱系的病毒至少已 4 次传播给人类，导致了 HIV-1 组 M、N、O 和 P 的出现。为了确定 SIVgor 的地理分布、流行率和物种关联性，我们对中非野生大猩猩进行了全面的分子流行病学调查。我们在西部低地大猩猩（n = 2,367）和东部山地大猩猩（n = 183）的活动范围内采集了大猩猩粪便样本，并对其进行了 SIVgor 抗体和核酸检测。在喀麦隆的 2 个地点发现了 SIVgor 抗体阳性样本，而在包括东部大猩猩活动范围的 19 个其他地点均未发现感染，在喀麦隆，基于对一组样本的 DNA 和微卫星分析，我们估计 SIVgor 的流行率为 1.6%（范围，0%至 4.6%），明显低于黑猩猩中 SIVcpzPtt 的流行率（5.9%；范围，0%至 32%）。所有新鉴定的 SIVgor 毒株在 SIVcpz 辐射中形成一个单系谱系，与 HIV-1 组 O 和 P 密切相关，并根据其野外来源地点聚类。在一个地点，有证据表明存在跨群体传播和高群体内流行率。这些孤立的 SIVgor 感染大猩猩群体热点可能成为人类感染的源头。SIVgor 的总体低流行率和分散分布可能表明 SIVgor 在野生种群中减少，但不能排除 SIVgor 在大猩猩地理分布的其他地区更为普遍。
