Malasao Rungnapa, Khamrin Pattara, Kumthip Kattareeya, Ushijima Hiroshi, Maneekarn Niwat
Department of Community Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
Center of Excellence in Emerging and Re-emerging Diarrheal Viruses, Chiang Mai University, Chiang Mai, Thailand.
Arch Virol. 2019 Jul;164(7):1743-1752. doi: 10.1007/s00705-019-04249-2. Epub 2019 Apr 10.
Little is known about human parechovirus (HPeV) infection in Thailand. The genotype distribution of HPeV strains in children admitted to hospitals with acute gastroenteritis was investigated using polymerase chain reaction (PCR) and nucleotide sequencing of the VP1 region as the detection and genotype identification methods, respectively. Of a total of 2,002 stool samples, 49 (2.4%) were positive for HPeV. Of these, HPeV-1 was the most predominant genotype (40.8%), followed by HPeV-3 (16.3%) and HPeV-14 (16.3%), while HPeV-5, -6, -2, -4, and -8 strains were less frequently detected, at 10.2%, 8.2%, 2%, 2%, and 2%, respectively. HPeV infections were detected throughout the year with the biannual peaks of infection in the rainy (Jun-Jul-Aug) and winter (Nov-Dec-Jan) months in Thailand. Based on VP1 amino acid sequence alignment, the arginyl-glycyl-aspartic acid (RGD) motif was found in HPeV-1, -2, -4, and -6 strains. Additionally, an amino acid insertion at the N-terminus of VP1 was observed in HPeV-4 and HPeV-5 strains. Phylogenetic analysis revealed that small clades of HPeV-1 and HPeV-3 strains emerged in 2016 and 2015, respectively, and dominated in the year of their emergence. The HPeV strains detected in Thailand in this study were most closely related to reference strains from Asia and Europe. The evolutionary rate of HPeV strains was 2.87 × 10 (95% highest posterior density (HPD) 0.10-6.14 × 10) substitutions/site/year. These findings provide information about the genetic diversity and evolutionary dynamics of HPeV genotypes circulating in pediatric patients with acute gastroenteritis in Thailand.
泰国人细小病毒（HPeV）感染的相关情况鲜为人知。采用聚合酶链反应（PCR）和VP1区域的核苷酸测序分别作为检测和基因型鉴定方法，对因急性肠胃炎入院的儿童中HPeV毒株的基因型分布进行了调查。在总共2002份粪便样本中，49份（2.4%）HPeV呈阳性。其中，HPeV-1是最主要的基因型（40.8%），其次是HPeV-3（16.3%）和HPeV-14（16.3%），而HPeV-5、-6、-2、-4和-8毒株的检出频率较低，分别为10.2%、8.2%、2%、2%和2%。泰国全年均检测到HPeV感染，在雨季（6月至7月至8月）和冬季（11月至12月至1月）出现感染的双年度高峰。基于VP1氨基酸序列比对，在HPeV-1、-2、-4和-6毒株中发现了精氨酰-甘氨酰-天冬氨酸（RGD）基序。此外，在HPeV-4和HPeV-5毒株中观察到VP1 N端的氨基酸插入。系统发育分析显示，HPeV-1和HPeV-3毒株的小分支分别于2016年和2015年出现，并在出现当年占主导地位。本研究在泰国检测到的HPeV毒株与来自亚洲和欧洲的参考毒株关系最为密切。HPeV毒株的进化速率为2.87×10（95%最高后验密度（HPD）0.10-6.14×10）替换/位点/年。这些发现提供了有关泰国急性肠胃炎儿科患者中流行的HPeV基因型的遗传多样性和进化动态的信息。
