Rotaviruses are non-enveloped double-stranded RNA virus that causes acute diarrheal diseases in children(<5 years).More than 90%of the global rotavirus infection in humans was caused by Rotavirus group A.Rotavirus infection has caused more than 200000 deaths annually and predominantly occurs in the low-income countries.Rotavirus evolution is indicated by the strain dynamics or the emergence of the unprecedented strain.The major factors that drive the rotavirus evolution include the genetic shift that is caused by the reassortment mechanism,either in the intra-or the inter-genogroup.However,other factors are also known to have an impact on rotavirus evolution.This review discusses the structure and types,epidemiology,and evolution of rotaviruses.This article also reviews other supplemental factors of rotavirus evolution,such as genetic reassortment,mutation rate,glycan specificity,vaccine introduction,the host immune respo-nses,and antiviral drugs.
Mohamad Saifudin HakimFaris Muhammad GazaliSuci Ardini WidyaningsihMohammad Khalid Parvez
The oral hexavalent live human-bovine reassortant rotavirus vaccine(RV6)developed by Wuhan Institute of Biological Products Co.,Ltd(WIBP)has finished a randomized,placebo-controlled phase III clinical trial in four provinces of China in 2021.The trail demonstrated that RV6 has a high vaccine efficacy against the prevalent strains and is safe for use in infants.During the phase III clinical trial(2019–2021),200 rotavirus-positive fecal samples from children with RV gastroenteritis(RVGE)were further studied.Using reverse transcription-polymerase chain reaction and high-throughput sequencing,VP7 and VP4 sequences were obtained and their genetic characteristics,as well as the differences in antigenic epitopes of VP7,were analyzed in detail.Seven rotavirus genotypes were identified.The predominant rotavirus genotype was G9P[8](77.0%),followed by prevalent strains G8P[8](8.0%),G3P[8](3.5%),G3P[9](1.5%),G1P[8](1.0%),G2P[4](1.0%),and G4P[6](1.0%).The amino acid sequence identities of G1,G2,G3,G4,G8,and G9 genotypes of isolates compared to the vaccine strains were 98.8%,98.2%–99.7%,88.4%–99.4%,98.2%,94.2%–100%,and 93.9%–100%,respectively.Notably,the vaccine strains exhibited high similarity in amino acid sequence,with only minor differences in antigenic epitopes compared to the Chinese endemic strains.This supports the potential application of the vaccine in preventing diseases caused by rotaviruses.
轮状病毒(rotavirus,RV)是引起人类和动物急性胃肠炎的重要病原体。结构蛋白VP8*(viral protein 8*,VP8*)位于RV最外层的刺突状VP4的头部,VP8*在受体识别和结合中发挥重要作用。目前对RV受体结合特性的研究主要集中在A组轮状病毒(group A rotavirus,RVA)和C组轮状病毒(group C rotavirus,RVC)。本文对RV的蛋白结构、受体类型以及RVA和RVC受体结合特性及与受体相互作用的结构基础等研究进展进行综述。
轮状病毒(Rotaviruses,RVs)是引起人和动物病毒性腹泻的重要病原,本文旨在研究猪C组轮状病毒(Group C rotaviruses,RVCs)VP8*蛋白的受体结合特征。本研究合成一株P[5]型猪C组轮状病毒(Por2011)的VP8*基因,经体外原核表达,采用亲和层析纯化获得VP8*目的蛋白,利用糖点阵实验、寡糖结合实验研究其寡糖结合特征,再通过序列比对和突变分析确定其潜在受体结合位点。结果显示猪C组轮状病毒Por2011 VP8*蛋白与P1抗原特异性结合,但第108位氨基酸突变后的蛋白则不能与P1抗原结合。本研究表明猪C组轮状病毒的某些型别可能以P1抗原为潜在受体,该受体结合位点与人C组轮状病毒的受体结合位点较为接近,这为猪C组轮状病毒感染机制的研究提供了一定的依据和基础。
This is the first country-wide surveillance of bat-borne viruses in Kenya spanning from 2012-2015 covering sites perceived to have medium to high level bat-human interaction. The objective of this surveillance study was to apply a non-invasive approach using fresh feces to detect viruses circulating within the diverse species of Kenyan bats. We screened for both DNA and RNA viruses; specifically, astroviruses （AstVs）, adenoviruses （ADVs）, caliciviruses （CalVs）, coronaviruses （CoVs）, flaviviruses, filoviruses, paramyxoviruses （PMVs）, polyomaviruses （PYVs） and rotaviruses. We used family-specific primers, amplicon sequencing and further characterization by phyloge- netic analysis. Except for filoviruses, eight virus families were detected with varying distributions and positive rates across the five regions （former provinces） studied. AstVs （12.83%）, CoVs （3.97%）, PMV （2.4%）, ADV （2.26%）, PYV （1.65%）, CalVs （0.29%）, rotavirus （0.19%） and flavivirus （0.19%）. Novel CalVs were detected in Rousettus aegyptiacus and Mops condylurus while novel Rotavirus-A-related viruses were detected in Taphozous bats and R. aegyptiacus. The two Rotavirus A （RVA） strains detected were highly related to human strains with VP6 genotypes 12 and 116. Genotype 116 has previously been assigned to human RVA-strain B10 from Kenya only, which raises public health concern, particularly considering increased human-bat interaction. Additionally, 229E-like bat CoVs were detected in samples originating from Hipposideros bats roosting in sites with high human activity. Our findings confirm the presence of diverse viruses in Kenyan bats while providing extended knowledge on bat virus distribution. The detection of viruses highly related to human strains and hence of public health concern, underscores the importance of continuous surveillance.
