Department of Medical Research, MacKay Memorial Hospital, Taipei 10449, Taiwan.
Department of Nursing, Shu-Zen junior College of Medicine and Management, Kaohsiung 82144, Taiwan.
Int J Environ Res Public Health. 2020 Feb 8;17(3):1086. doi: 10.3390/ijerph17031086.
Human bocavirus (HBoV) is a causative agent of respiratory and gastrointestinal diseases worldwide. Four HBoV species (HBoV1-4) have been identified so far. Although a previous report has documented the HBoV association with acute gastroenteritis (AGE) in Taiwan, their epidemiology, genetic diversity, and phylogenetic relationships remain unclear. In this study, we focused on an investigation of these unsolved issues, which will help to reveal molecular epidemiology and phylogeny of the circulating HBoV2 in Taiwan. A total of 176 stool samples were collected from children with AGE for this study. PCR amplification and sequencing on the VP1 gene region were used to identify species. Phylogenetic analysis was conducted by maximum-likelihood and neighbor-joining methods. Selection pressure was also estimated to obtain HBoV evolutionary information. Our results showed the prevalence of HBoV in AGE children was 8.5%, of which HBoV1 was the predominant species (6.3%), followed by HBoV2 (2.3%). Phylogenetic analysis showed those Taiwanese HBoV2 strains have significant genetic variability and can be divided into two clusters. One belongs to HBoV2 genotype A and the other forms an independent unclassified cluster. The nucleotide distance between that independent cluster and the known HBoV2 genotypes was more than 5%, suggesting a new HBoV2 genotype. No positive selection site was found and the virus was under purifying selection. This is the first report to reveal HBoV2 genetic diversity and phylogenetic relationships among AGE children in Taiwan. We find that HBoV2 may have been introduced into the country by multiple origins, and a potential new HBoV2 genotype is proposed.
人博卡病毒（HBoV）是一种引起全球呼吸道和胃肠道疾病的病原体。迄今为止，已经确定了四种 HBoV 物种（HBoV1-4）。尽管之前有报道称 HBoV 与台湾的急性胃肠炎（AGE）有关，但它们的流行病学、遗传多样性和系统发育关系仍不清楚。在本研究中，我们专注于调查这些未解决的问题，这将有助于揭示台湾流行的 HBoV2 的分子流行病学和系统发育。本研究共收集了 176 份来自 AGE 儿童的粪便样本。使用 VP1 基因区域的 PCR 扩增和测序来鉴定物种。通过最大似然法和邻接法进行系统发育分析。还估计了选择压力以获得 HBoV 的进化信息。我们的研究结果表明，HBoV 在 AGE 儿童中的流行率为 8.5%，其中 HBoV1 是主要的物种（6.3%），其次是 HBoV2（2.3%）。系统发育分析表明，这些台湾 HBoV2 株具有显著的遗传变异性，可分为两个聚类。一个属于 HBoV2 基因型 A，另一个形成独立的未分类聚类。该独立聚类与已知的 HBoV2 基因型之间的核苷酸距离超过 5%，提示存在一种新的 HBoV2 基因型。未发现阳性选择位点，病毒处于纯化选择之下。这是首次报道揭示台湾 AGE 儿童中 HBoV2 的遗传多样性和系统发育关系。我们发现 HBoV2 可能通过多种来源引入该国，并提出了一种潜在的新 HBoV2 基因型。
