Enteric Viruses Group, ICMR-National Institute of Virology, Pune, India.
Maulana Azad Medical College and Lok Nayak Hospital, New Delhi, India.
J Med Virol. 2022 Jun;94(6):2613-2623. doi: 10.1002/jmv.27468. Epub 2021 Dec 2.
Rotaviruses (RVs) are the major causative agents of acute gastroenteritis in children, but in neonates, RV infections are generally nosocomial in origin and mostly asymptomatic. However, there have been infrequent reports of nosocomial outbreaks of clinical disease in this population. In this study, we describe uncommon RV genotype; G12P[11] associated with an outbreak of acute gastroenteritis in the neonatal ward and neonatal intensive care unit (NICU) in New Delhi, North India. Full-genome analyses of the pathogenic G12P[11] strain was carried out to map the genotype constellation and further to explore the variations in the antigenic epitopes on the immunodominant VP7 and VP4 proteins, the amino acid sequences were compared with neonatal strains; ROTAVAC® (G9P[11]) and asymptomatic G12P[11] and also other G/P-type matched strains. The study revealed G12-P[11]-I1-R1-C1-M1-A1-N1-T1-E1-H1 human Wa-like genotype constellation and highlights evidence of gene reassortment. No significant differences were observed in the sequences of structural (except VP3) and nonstructural encoding genes of G12P[11] strains recovered from symptomatic and asymptomatic neonates. Presence of additional N-linked glycosylation site was noted in the G12 strains, as a consequence of a change from Asp→Asn at amino acid position 238. Interestingly, only two and four amino acids substitution within the 7-1a and 8-1 antigenic epitope were observed, respectively, compared with asymptomatic G12P[11] strain. The study emphasizes the importance of close monitoring of RV outbreaks in neonates for early alarming of novel strain.
轮状病毒（RV）是导致儿童急性肠胃炎的主要病原体，但在新生儿中，RV 感染通常为医院感染，且大多无症状。然而，在该人群中，偶有医院感染爆发临床疾病的报道。在本研究中，我们描述了一种不常见的 RV 基因型；G12P[11]与印度北部新德里新生儿病房和新生儿重症监护病房（NICU）爆发的急性肠胃炎有关。对致病性 G12P[11]株进行了全基因组分析，以绘制基因型图谱，并进一步探索免疫显性 VP7 和 VP4 蛋白上抗原表位的变异，将氨基酸序列与新生儿株；ROTAVAC®（G9P[11]）和无症状 G12P[11]以及其他 G/P 型匹配株进行比较。研究揭示了 G12-P[11]-I1-R1-C1-M1-A1-N1-T1-E1-H1 人 Wa 样基因型图谱，并强调了基因重配的证据。从有症状和无症状新生儿中分离出的 G12P[11]菌株的结构（VP3 除外）和非结构编码基因的序列没有观察到显著差异。在 G12 株中，由于在氨基酸位置 238 处从天冬氨酸（Asp）变为天冬酰胺（Asn），观察到额外的 N 连接糖基化位点。有趣的是，与无症状 G12P[11]株相比，在 7-1a 和 8-1 抗原表位内分别仅观察到两个和四个氨基酸取代。本研究强调了密切监测新生儿中 RV 爆发的重要性，以便早期预警新菌株。
