Tiku Vasundhara Razdan, Jiang Baoming, Kumar Praveen, Aneja Satender, Bagga Arvind, Bhan Maharaj Kishen, Ray Pratima
Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India.
Centers for Disease Control and Prevention, Atlanta, USA.
Virol J. 2017 May 30;14(1):100. doi: 10.1186/s12985-017-0767-8.
Group C Rotavirus (RVC) is an enteric pathogen responsible for acute gastroenteritis in children and adults globally. At present there are no surveillance studies on group C Rotaviruses in India and therefore their prevalence in India remains unknown. The present study aimed to evaluate group C rotavirus infection among <5 years old children hospitalized with acute gastroenteritis in New Delhi.
A total of 350 fecal specimens were collected during September 2013 to November 2014 from <5 years old diarrheal patients admitted at KSCH hospital, Delhi. The samples found negative for group A rotavirus (N = 180) by Enzyme immunoassay were screened for group C rotavirus by RT-PCR with VP6, VP7 and VP4 gene specific primers. The PCR products were further sequenced (VP6, VP7, VP4) and analyzed to ascertain their origin and G and P genotypes.
Six out of 180 (group A rotavirus negative) samples were found positive for group C rotavirus by VP6 gene specific RT-PCR, of which 3 were also found positive for VP7 and VP4 genes. Phylogenetic analysis of VP7 and VP4 genes of these showed them to be G4 and P[2] genotypes. Overall, the nucleotide sequence data (VP6, VP7 and VP4) revealed a close relationship with the human group C rotavirus with no evidence of animal ancestry. Interestingly, the nucleotide sequence analysis of various genes also indicated differences in their origin. While the identity matrix of VP4 gene (n = 3) showed high amino acid sequence identity (97.60 to 98.20%) with Korean strain, the VP6 gene (n = 6) showed maximum identity with Nigerian strain (96.40 to 97.60%) and VP7 gene (n = 3) with Bangladeshi and USA strains. This is true for all analyzed samples.
Our study demonstrated the group C rotavirus as the cause of severe diarrhea in young children in Delhi and provides insights on the origin of group C rotavirus genes among the local strains indicating their source of transmission. Our study also highlights the need for a simple and reliable diagnostic test that can be utilized to determine the disease burden due to group C rotavirus in India.
C组轮状病毒(RVC)是一种肠道病原体,在全球范围内可导致儿童和成人患急性肠胃炎。目前印度尚无关于C组轮状病毒的监测研究,因此其在印度的流行情况仍不明确。本研究旨在评估新德里因急性肠胃炎住院的5岁以下儿童中C组轮状病毒感染情况。
2013年9月至2014年11月期间,从德里KSCH医院收治的5岁以下腹泻患者中总共收集了350份粪便标本。通过酶免疫测定法检测发现A组轮状病毒呈阴性的样本(N = 180),使用VP6、VP7和VP4基因特异性引物通过逆转录聚合酶链反应(RT-PCR)对C组轮状病毒进行筛查。对PCR产物进一步测序(VP6、VP7、VP4)并进行分析,以确定其来源以及G和P基因型。
在180份(A组轮状病毒阴性)样本中,有6份通过VP6基因特异性RT-PCR检测出C组轮状病毒呈阳性,其中3份VP7和VP4基因也呈阳性。对这些样本的VP7和VP4基因进行系统发育分析,结果显示它们为G4和P[2]基因型。总体而言,核苷酸序列数据(VP6、VP7和VP4)表明其与人类C组轮状病毒关系密切,没有动物起源的证据。有趣的是,对各种基因的核苷酸序列分析也表明它们的来源存在差异。虽然VP4基因(n = 3)的同一性矩阵显示与韩国毒株具有较高的氨基酸序列同一性(97.60%至98.20%),但VP6基因(n = 6)与尼日利亚毒株的同一性最高(96.40%至97.60%),VP7基因(n = 3)与孟加拉国和美国毒株的同一性最高。所有分析样本均如此。
我们的研究证明C组轮状病毒是德里幼儿严重腹泻的病因,并对当地毒株中C组轮状病毒基因的起源提供了见解,表明了它们的传播来源。我们的研究还强调需要一种简单可靠的诊断测试,可用于确定印度C组轮状病毒导致的疾病负担。