van Meer Vanessa, Pawęska Janusz T, Swanepoel Robert, Grobbelaar Antoinette, Bastos Armanda D
Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Hatfield 0028, South Africa.
Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases, National Health Laboratory Service, Johannesburg 2131, South Africa.
Pathogens. 2024 Mar 19;13(3):261. doi: 10.3390/pathogens13030261.
From 1993 to 1994, 64 free-ranging elephants () succumbed to encephalomyocarditis in the Kruger National Park, South Africa, of which 83% were adult bulls. rodents were implicated as the reservoir host of the (EMCV) based on serology and RT-PCR. However, in the absence of sequence-confirmation of both the virus and the rodent host, definitive links between the elephant outbreak strains and rodent reservoir could not be established. In this study, we generate the first reference genome sequences for three historical EMCVs isolated from two rodents and one -associated mite, , in Gauteng Province, South Africa, in 1961. In addition, near-complete genome sequences were generated for two elephant outbreak virus strains, for which data were previously limited to the P1 and 3D genome regions. The consensus sequence of each virus was determined using a PCR-Sanger sequencing approach. Phylogenetic analysis confirmed the three near-identical (99.95-99.97%) -associated viruses to be sister to the two near-identical (99.85%) elephant outbreak strains, differing from each other at 6.4% of sites across the ~7400-nucleotide region characterised. This study demonstrates a link between -associated viruses and the historical elephant outbreak strains and implicates as reservoirs of EMCV in South Africa.
1993年至1994年期间,南非克鲁格国家公园有64头自由放养的大象死于脑心肌炎,其中83%为成年雄象。基于血清学和逆转录聚合酶链反应(RT-PCR),啮齿动物被认为是脑心肌炎病毒(EMCV)的储存宿主。然而,由于缺乏病毒和啮齿动物宿主的序列确认,无法确定大象疫情毒株与啮齿动物储存宿主之间的明确联系。在本研究中,我们首次获得了1961年从南非豪登省的两只啮齿动物和一只与啮齿动物相关的螨虫(Ornithonyssus bacoti)中分离出的三种历史脑心肌炎病毒的参考基因组序列。此外,还获得了两种大象疫情病毒毒株的近乎完整的基因组序列,此前关于这两种毒株的数据仅限于P1和3D基因组区域。使用聚合酶链反应-桑格测序方法确定了每种病毒的共有序列。系统发育分析证实,三种近乎相同(99.95%-99.97%)的与啮齿动物相关的病毒是两种近乎相同(99.85%)的大象疫情毒株的姐妹株,在约7400个核苷酸区域的6.4%位点上彼此不同。这项研究证明了与啮齿动物相关的病毒与历史上的大象疫情毒株之间的联系,并表明啮齿动物是南非脑心肌炎病毒的储存宿主。