BACKGROUND Pteropine orthoreovirus (PRV) is an emerging bat-borne zoonotic virus that causes severe respiratory illness in humans. Although PRVs have been identified in fruit bats and humans in Australia and Asia, little is known about the prevalence of PRV infection in Africa. Therefore, this study performed an PRV surveillance in fruit bats in Zambia. METHODS Egyptian fruit bats (Rousettus aegyptiacus, n = 47) and straw-colored fruit bats (Eidolon helvum, n = 33) captured in Zambia in 2017-2018 were screened for PRV infection using RT-PCR and serum neutralization tests. The complete genome sequence of an isolated PRV strain was determined by next generation sequencing and subjected to BLAST and phylogenetic analyses. Replication capacity and pathogenicity of the strain were investigated using Vero E6 cell cultures and BALB/c mice, respectively. RESULTS An PRV strain, tentatively named Nachunsulwe-57, was isolated from one Egyptian fruit bat. Serological assays demonstrated that 98% of sera (69/70) collected from Egyptian fruit bats (n = 37) and straw-colored fruit bats (n = 33) had neutralizing antibodies against PRV. Genetic analyses revealed that all 10 genome segments of Nachunsulwe-57 were closely related to a bat-derived Kasama strain found in Uganda. Nachunsulwe-57 showed less efficiency in viral growth and lower pathogenicity in mice than another PRV strain, Miyazaki-Bali/2007, isolated from a patient. CONCLUSIONS A high proportion of Egyptian fruit bats and straw-colored fruit bats were found to be seropositive to PRV in Zambia. Importantly, a new PRV strain (Nachunsulwe-57) was isolated from an Egyptian fruit bat in Zambia, which had relatively weak pathogenicity in mice. Taken together, our findings provide new epidemiological insights about PRV infection in bats and indicate the first isolation of an PRV strain that may have low pathogenicity to humans.

中文翻译：

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从赞比亚的一只埃及果蝠中分离出的 Pteropine orthoreovirus 引起的减毒感染。

背景 蝶呤正则病毒 (PRV) 是一种新兴的蝙蝠传播的人畜共患病毒，可导致人类严重的呼吸道疾病。尽管已经在澳大利亚和亚洲的果蝠和人类中发现了 PRV，但对非洲 PRV 感染的流行情况知之甚少。因此，本研究对赞比亚的果蝠进行了 PRV 监测。方法 对 2017-2018 年在赞比亚捕获的埃及果蝠（Rousettus aegyptiacus，n = 47）和稻草色果蝠（Eidolon helvum，n = 33）使用 RT-PCR 和血清中和试验筛选 PRV 感染。分离的 PRV 菌株的完整基因组序列由下一代测序确定，并进行 BLAST 和系统发育分析。分别使用 Vero E6 细胞培养物和 BALB/c 小鼠研究该菌株的复制能力和致病性。结果 从一只埃及果蝠中分离出一种 PRV 品系，暂定名为 Nachunsulwe-57。血清学分析表明，从埃及果蝠（n = 37）和稻草色果蝠（n = 33）收集的 98% 的血清 (69/70) 具有针对 PRV 的中和抗体。遗传分析显示，Nachunsulwe-57 的所有 10 个基因组片段都与在乌干达发现的源自蝙蝠的 Kasama 菌株密切相关。与从患者身上分离的另一种 PRV 毒株 Miyazaki-Bali/2007 相比，Nachunsulwe-57 在小鼠中表现出较低的病毒生长效率和较低的致病性。结论 在赞比亚发现高比例的埃及果蝠和稻草色果蝠对 PRV 呈血清阳性。重要的是，从赞比亚的一只埃及果蝠中分离出一种新的 PRV 毒株（Nachunsulwe-57），该毒株对小鼠的致病性相对较弱。