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The emergence of unusual G9P[8]-E2 human rotaviruses in the Tokyo metropolitan area, Japan, in 2018 has been reported. During rotavirus strain surveillance in different regions of Japan (Mie, Okayama, and Chiba prefectures), G9P[8]-E2 strains were detected in children with diarrhea from all three prefectures. Here, we characterized the whole genome of seven representative G9P[8]-E2 strains. In the full-genome-based analysis, the seven study strains exhibited a unique genotype configuration with the NSP4 gene of genogroup 2 in a genogroup 1 genomic backbone: G9-P[8]-I1-R1-C1-M1-A1-N1-T1-E2-H1. This genotype constellation was shared by the Tokyo G9P[8]-E2 strains. Phylogenetic analysis showed that all 11 genes, except NSP4, of the seven study strains appeared to have originated from co-circulating Wa-like G9P[8]-E1 strains. In contrast, NSP4 appeared to have originated from the co-circulating DS-1-like G2P[4]-E2 strains. Thus, G9P[8]-E2 strains appear to be derived through reassortment between G9P[8]-E1 and G2P[4]-E2 strains in Japan. Notably, the seven study G9P[8]-E2 strains and Tokyo G9P[8]-E2 strains were revealed to have 11-segment genomes almost indistinguishable from one another in their sequences (99.3-100%), indicating all these G9P[8]-E2 strains had a common origin. To our knowledge, this is the first description of the rapid spread of G9P[8]-E2 strains across a country.

Purpose The purpose of this study is to propose a method for vulnerable pedestrians to visualize potential obstacles on sidewalks. In recent years, the number of vulnerable pedestrians has been increasing as Japanese society has aged. The number of wheelchair users is also expected to increase in the future. Currently, barrier-free maps and street-view applications can be used by wheelchair users to check possible routes and the surroundings of their destinations in advance. However, identifying physical barriers that pose a threat to vulnerable pedestrians en route is often difficult. Design/methodology/approach This study uses photogrammetry to create a digital twin of the three-dimensional (3D) geometry of the existing walking space by collecting photographic images taken on sidewalks. This approach allows for the creation of high-resolution digital elevation models of the entire physical sidewalk surface from which physical barriers such as local gradients and height differences can be detected by uniform image filtering. The method can be used with a Web-based data visualization tool in a geographical information system, permitting first-person views of the ground and accurate geolocation of the barriers on the map. Findings The findings of this study showed that capturing the road surface with a small wide-angle camera while walking is sufficient for recording subtle 3D undulations in the road surface. The method used for capturing data and the precision of the 3D restoration results are described. Originality/value The proposed approach demonstrates the significant benefits of creating a digital twin of walking space using photogrammetry as a cost-effective means of balancing the acquisition of 3D data that is sufficiently accurate to show the detailed geometric features needed to navigate a walking space safely. Further, the findings showed how information can be provided directly to users through two-dimensional (2D) and 3D Web-based visualizations.

Background Herpes simplex virus type 2 (HSV-2) can cause genital herpes, which reduces the patient's QOL associated with pain. In addition, genital herpes can increase the risk of human immunodeficiency virus infection. Vaccine development has been attempted for many years, but it has not yet been put into practical use. Meanwhile, rotavirus (RV) is one of the major viral causes of severe gastroenteritis in infants and young children worldwide. Currently, two live attenuated vaccines are widely used to prevent severe RV infection in children. We have developed entirely plasmid-based reverse genetics systems of RV, which allowed the generation of recombinant reassortant RV containing a foreign gene. In this study, we sought to develop simian RV (SA11), in which HSV-2 glycoprotein D (gD2) gene was inserted by reverse genetics system, as a herpes vaccine, and evaluated its immunogenicity in mice. Construction of HSV-2 protein expressing rotavirus as a vaccine inducing mucosal immunity Methods Artificially synthesized gD2 DNA fragment was inserted into T7 expression NSP1 plasmids (pT7/NSP1-gD2). Using the plasmid, recombinant SA11-gD2 virus (rSA11-gD2) was generated. gD2 protein expression in infected MA104 cells was verified by Western blotting. rSA11-gD2 was orally inoculated into BALB/c suckling mice twice two weeks apart and into eight-week-old mice three times apart four weeks. Diarrhea score was evaluated for seven days after first inoculation in suckling mice. Serum IgG and IgA titers against RV and gD2 were measured by ELISA. Results Insertion of the gD2 gene and synthesis of gD2 protein were demonstrated by sequence analysis and Wester blotting analysis, respectively. Diarrhea occurred after the first inoculation of rSA11-gD2 in suckling mice. Although IgG and IgA antibodies against RV were induced, gD2 antibody was not detected in convalescent sera in the suckling mice. Meanwhile, in the eight-week-old mice inoculated with three times of rSA11-gD2, significant increases in not only IgG and IgA against RV but also IgG against gD2 were demonstrated. Conclusion Simian RV containing gD2 gene, which was developed by the reverse genetics, induced IgG antibody against gD2 in orally inoculated mice. This strategy can be used to develop genital herpes vaccine. Disclosures All Authors: No reported disclosures.

The exact evolutionary patterns of human G4P[6] rotavirus strains remain to be elucidated. Such strains possess unique and strain-specific genotype constellations, raising the question of whether G4P[6] strains are primarily transmitted via independent interspecies transmission or human-to-human transmission after interspecies transmission. Two G4P[6] rotavirus strains were identified in fecal specimens from hospitalized patients with severe diarrhea in Thailand, namely, DU2014-259 (RVA/Human-wt/THA/DU2014-259/2014/G4P[6]) and PK2015-1-0001 (RVA/Human-wt/THA/PK2015-1-0001/2015/G4P[6]). Here, we analyzed the full genomes of the two human G4P[6] strains, which provided the opportunity to study and confirm their evolutionary origin. On whole genome analysis, both strains exhibited a unique Wa-like genotype constellation of G4-P[6]-I1-R1-C1-M1-A8-N1-T1-E1-H1. The NSP1 genotype A8 is commonly found in porcine rotavirus strains. Furthermore, on phylogenetic analysis, each of the 11 genes of strains DU2014-259 and PK2015-1-0001 appeared to be of porcine origin. On the other hand, the two study strains consistently formed distinct clusters for nine of the 11 gene segments (VP4, VP6, VP1-VP3, and NSP2-NSP5), strongly indicating the occurrence of independent porcine-to-human interspecies transmission events. Our observations provide important insights into the origin of zoonotic G4P[6] strains, and into the dynamic interaction between porcine and human rotavirus strains.

Avian rotavirus A (RVA) is one of major enteric pathogens that cause diarrhoea in young avian individuals. Importantly, some of the avian RVA strains of G18P[17] genotype are naturally transmitted to and cause clinical diseases in mammalian species, indicating their potential risks to animal health. Although molecular information on the pathogenesis by avian RVA strains will be useful for estimating their risks, the absence of a reverse genetics (RG) system for these strains has hindered the elucidation of their pathogenic mechanisms. In this study, we aimed to establish an RG system for the avian G18P[17] prototype strain PO-13, which was isolated from a pigeon in Japan in 1983 and was experimentally shown to be pathogenic in suckling mice. Transfection with plasmids expressing 11 genomic RNA segments of the strain resulted in rescue of the infectious virus with an artificially introduced genetic marker on its genome, indicating that an RG system for the PO-13 strain was successfully established. The rescued recombinant strain rPO-13 had biological properties almost identical to those of its wild-type strain (wtPO-13). Notably, both rPO-13 and wtPO-13 induced diarrhoea in suckling mice with similar efficiencies. It was thus demonstrated that the RG system will be useful for elucidating the pathogenic mechanisms of the PO-13 strain at the molecular level. This is the first report of the establishment of an RG system for an avian RVA strain.

The group A rotavirus (RVA) genome comprising 11 double-stranded RNAs encodes six structural proteins (VP1-VP4, VP6, and VP7) and six non-structural proteins (NSP1-NSP6). Among these 12 rotaviral proteins, NSP6 has been less studied as to its function. We previously prepared a recombinant NSP6-deficient RVA derived from simian strain SA11-L2 by reverse genetics, and found that the NSP6-deficient virus grew well in cell culture, although its growth was less abundant than that of the parental SA11-L2 strain. In this study, we examined the potency of a recombinant RVA incapable of NSP6 expression to cause diarrhoea in suckling mice. The suckling mice infected with the NSP6-deficient virus apparently experienced diarrhoea, although the symptom was milder and the duration of diarrhoea was shorter than in the mice infected with the authentic SA11-L2 strain. Thus, together with the results obtained for cultured cells in the previous study, it can be concluded that NSP6 is not necessarily required for replication and pathogenicity in vitro and in vivo.

Group A rotavirus (RVA) rarely causes severe complications such as encephalitis/encephalopathy. However, the pathophysiology of this specific complication remains unclear. We used next-generation sequence analysis to compare the entire genome sequences of RVAs detected in patients with encephalitis/encephalopathy and gastroenteritis. This study enrolled 8 patients with RVA encephalitis/encephalopathy and 10 with RVA gastroenteritis who were treated between February 2013 and July 2014. Viral RNAs were extracted from patients' stool, and whole-genome sequencing analysis was carried out to identify the specific gene mutations in RVA obtained from patients with severe neurological complications. Among the 8 encephalitis/encephalopathy cases, 6 strains were DS-1-like G1P[8] and the remaining 2 were Wa-like G1P[8] (G1-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1). Meanwhile, 8 of the 10 viruses detected in rotavirus gastroenteritis patients were DS-1-like G1P[8], and the remaining 2 were Wa-like G1P[8]. We further characterized these strains by conducting phylogenetic analysis. No specific clustering was demonstrated in RVAs detected from encephalitis/encephalopathy patients. Although the DS-1-like G1P[8] strain was predominant in both groups, no specific molecular characteristics were detected in RVAs from patients with severe central nervous system complications. This article is protected by copyright. All rights reserved.

Reassortment is an important mechanism in the evolution of group A rotaviruses (RVAs), yielding viruses with novel genetic and phenotypic traits. The classical methods for generating RVA reassortants with the desired genetic combinations are laborious and time-consuming because of the screening and selection processes required to isolate a desired reassortant. Taking advantage of a recently developed RVA reverse genetics system based on just 11 cloned cDNAs encoding the RVA genome (11 plasmid-only system), we prepared a panel of simian SA11-L2 virus-based single-gene reassortants, each containing 1 segment derived from human KU virus of the G1P[8] genotype. It was shown that there was no gene-specific restriction of the reassortment potential. In addition to these 11 single-gene reassortants, a triple-gene reassortant with KU-derived core-encoding VP1–3 gene segments with the SA11-L2 genetic background, which make up a virion composed of the KU-based core, and SA11-L2-based intermediate and outer layers, could also be prepared with the 11 plasmid-only system. Finally, for possible clinical application of this system, we generated a series of VP7 reassortants representing all the major human RVA G genotypes (G1–4, G9 and G12) efficiently. The preparation of each of these single-gene reassortants was achieved within just 2 weeks. Our results demonstrate that the 11 plasmid-only system allows the rapid and reliable generation of RVA single-gene reassortants, which will be useful for basic research and clinical applications.

Species A rotaviruses are a major cause of acute gastroenteritis in infants and young children worldwide. Reassortment is a common phenomenon due to the segmented nature of the rotavirus genome. The complete coding sequences of a species A rotavirus strain isolated from the feces of a child with acute gastroenteritis in Japan in 2018 were determined using an unbiased viral metagenomics approach. The genetic analysis revealed that the rotavirus strain had an unusual genomic constellation (G1-P[8]-I1-R1-C1-M1-A1-N1-T1-E2-H1), suggesting reassortment of a genotype 1 with a genotype 2 rotavirus, from which the NSP4-encoding gene was acquired.

A reverse genetics technology is an incredibly useful technique both for a proper understanding of different aspects of virus biology and for the generation of complementary DNA (cDNA)-derived infectious viruses, which can act as safe and effective vaccines and viral vectors. Rotaviruses (RVAs), especially human RVAs (HuRVAs), had been very refractory to this technology until very recently. Here, we describe the historical background of the development of a long-awaited HuRVA reverse genetics system, culminating in the generation of replicative HuRVAs entirely from cloned cDNAs.

Group A rotavirus (RVA) is a major cause of acute gastroenteritis in infants and young children worldwide. This study aims to clarify the distribution of G/P types and genetic characteristics of RVAs circulating in Thailand. Between January 2014 and September 2016, 1867 stool specimens were collected from children and adults with acute gastroenteritis in six provinces in Thailand. RVAs were detected in 514/1867 (27.5%) stool specimens. G1P[8] (44.7%) was the most predominant genotype, followed by G3P[8] (33.7%), G2P[4] (11.5%), G8P[8] (7.0%), and G9P[8] (1.3%). Unusual G3P[9] (0.8%), G3P[10] (0.4%), G4P[6] (0.4%), and G10P[14] (0.2%) were also detected at low frequencies. The predominant genotype, G1P[8] (64.4%), in 2014 decreased to 6.1% in 2016. In contrast, the frequency of G3P[8] markedly increased from 5.5% in 2014 to 65.3% in 2015 and 89.8% in 2016. On polyacrylamide gel electrophoresis, most (135/140; 96.4%) of the G3P[8] strains exhibited a short RNA profile. Successful determination of the nucleotide sequences of the VP7 genes of 98 G3P[8] strains with a short RNA profile showed that they are all equine-like G3P[8] strains. On phylogenetic analysis of genome segments of two representative Thai equine-like G3P[8] strains, it was noteworthy that they possessed distinct NSP4 genes, one bovine-like and the other human-like. Thus, we found that characteristic equine-like G3P[8] strains with a short RNA electropherotype are becoming highly prevalent in children and adults in Thailand.

A monovalent rotavirus vaccine (RV1) was introduced to the national immunization program in Kenya in July 2014. There was increased detection of uncommon G3P[6] strains that coincided temporally with the timing of this vaccine introduction. Here, we sequenced and characterized the full genomes of two post-vaccine G3P[6] strains, RVA/Human-wt/KEN/KDH1951/2014/G3P[6] and RVA/Human-wt/KEN/KDH1968/2014/G3P[6], as representatives of these uncommon strains. On full-genomic analysis, both strains exhibited a DS-1-like genotype constellation: G3-P[6]-I2-R2-C2-M2-A2-N2-T2-E2-H2. Phylogenetic analysis revealed that all 11 genes of strains KDH1951 and KDH1968 were very closely related to those of human G3P[6] strains isolated in Uganda in 2012–2013, indicating the derivation of these G3P[6] strains from a common ancestor. Because the uncommon G3P[6] strains that emerged in Kenya are fully heterotypic as to the introduced vaccine strain regarding the genotype constellation, vaccine effectiveness against these G3P[6] strains needs to be closely monitored.

With the recent establishment of robust reverse genetics systems for rotavirus, rotavirus is being developed as a vector to express foreign genes. However, insertion of larger sequences such as those encoding multiple foreign genes into the rotavirus genome has been challenging because the virus segments are small. In this paper, we attempted to insert multiple foreign genes into a single gene segment of rotavirus to determine whether it can efficiently express multiple exogenous genes from its genome. At first, we engineered a truncated NSP1 segment platform lacking most of the NSP1 open reading frame and including a self-cleaving 2A sequence (2A), which made it possible to generate a recombinant rotavirus stably expressing NanoLuc (Nluc) luciferase as a model foreign gene. Based on this approach, we then demonstrated the generation of a replication-competent recombinant rotavirus expressing three reporter genes (Nluc, EGFP, and mCherry) by separating them with self-cleaving 2As, indicating the capacity of rotaviruses as to the insertion of multiple foreign genes. Importantly, the inserted multiple foreign genes remained genetically stable during serial passages in cell culture, indicating the potential of rotaviruses as attractive expression vectors. The strategy described here will serve as a model for the generation of rotavirus-based vectors designed for the expression and/or delivery of multiple foreign genes.

BACKGROUND Acute gastroenteritis is the most common cause of illness and death in infants and young children worldwide. Rotaviruses (RVs) are the major viruses that cause acute gastroenteritis in young children, especially in developing countries in Asia and Africa. METHODS The presence of rotavirus antigens in sera of four unvaccinated pediatric patients, aged between 4 and 6 years with severe diarrhea and dehydration, were detected by using three immunochromatographic (IC) kits. In addition, the presence of anti-rotavirus IgG, IgA, and IgM antibodies and their concentrations in patient sera were also determined by enzyme immunoassay (EIA). RESULTS All three kits could detect rotavirus antigen in patient sera with different intensity of the test lines. When patient sera were pretreated with anti-VP6 rotavirus mouse monoclonal antibody prior to testing, the rotavirus positive test lines disappeared, suggesting that all patient sera contained VP6 protein antigen of rotavirus. Assessment of antibody concentration in these patient sera revealed that all patient sera contained IgG, IgA, and IgM antibodies against rotavirus antigen at different concentrations. CONCLUSIONS The sensitivity of rotavirus protein detection in the patient sera of one IC kit brand was comparable to those of the EIA, suggesting this IC kit could be an alternative screening method for rapid diagnosis of rotavirus infection.

Group A rotavirus is a leading cause of severe acute gastroenteritis worldwide. In this study, the first complete coding sequences of 11 RNA segments of human group A rotavirus G12P[8] in Japan were determined by an unbiased viral metagenomics. Its genomic constellation (VP7-VP4-VP6-VP1-VP2-VP3-NSP1-NSP2-NSP3-NSP4-NSP5 genes) was identified as G12-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1. When performing the genetic analysis, we discovered an intergenotypic recombination event in the pig group A rotavirus G12P[8] strain BUW-14-A008. The novel recombination was found between two different genotypes G12 and G3 in the VP7 gene, and P[8] and P[13] in the VP4 gene.

Background: The primary aldosteronism (PA) subtype is usually confirmed by computed tomography (CT) and adrenal venous sampling (AVS). However, the subtype diagnosis by AVS is not necessarily consistent with the subtype diagnosis by CT. Patients with PA who show normal-appearing adrenals on CT but unilateral disease on AVS (CT-negative and AVS-unilateral group) are often found. However, few studies have focused on them, despite a discrepancy between CT and AVS subtype diagnosis. Objective: The aim of this study was to evaluate the clinical features of CT-negative and AVS-unilateral group and assess whether they obtain benefits from surgery. Methods: We retrospectively analyzed 362 consecutive patients with PA who underwent both CT and adrenocorticotropic hormone (ACTH)-unstimulated AVS at Kanazawa University Hospital. First, the patients were divided into normal-appearing adrenals, bilateral adrenal nodules, or unilateral adrenal nodules based on CT findings. Second, they were classified as having unilateral or bilateral disease based on ACTH-unstimulated AVS. The criterion for successful selective catheterization was selectivity index >2 and unilateral aldosterone overproduction was confirmed by lateralized index ≥2. Among the group with normal appearing-adrenals on CT, we examined preoperative clinical characteristics between those with unilateral disease on AVS and those with bilateral disease on AVS. In addition, we compared surgical outcomes of CT-negative and AVS-unilateral group with those of CT-unilateral and AVS-ipsilateral group (patients with unilateral lesions on CT and ipsilateral disease on AVS). The Surgical outcomes for unilateral PA were evaluated according to the criteria of the Primary Aldosteronism Surgical Outcome study. Results: The success rate of AVS in patients with normal-appearing adrenals on CT was 88% (167/190). Furthermore, the discordance rate between CT and AVS in patients with normal-appearing adrenals on CT was 36% (60/167). There were no significant differences in preoperative clinical characteristics between the CT-negative and AVS-unilateral group (n=60) and the CT-negative and AVS-bilateral group (n=107). After surgery, the CT-negative and AVS-unilateral group (n=14) had a lower complete biochemical success rate than the CT-unilateral and AVS-ipsilateral group (n=30) (43% vs. 80%, p=0.02), but clinical and biochemical benefits (the complete and partial success combined) were not significantly different between them (71% vs. 93% (p=0.07) and 71% vs. 90% (p=0.13), respectively). Conclusion: The clinical features of CT-negative and AVS-unilateral group were significantly similar to those of CT-negative and AVS-bilateral group. They benefited from surgery, and AVS should be performed for patients who pursue surgical management when the CT findings suggest normal-appearing adrenals.

An unusual rotavirus strain, DB2015-066 with the G10P[14] genotype (RVA/Human-wt/THA/DB2015-066/2015/G10P[14]), was detected in a stool sample from a child hospitalized with acute gastroenteritis in Thailand. Here, we sequenced and characterized the full-genome of the strain DB2015-066. On whole genomic analysis, strain DB2015-066 was shown to have a unique genotype constellation: G10-P[14]-I2-R2-C2-M2-A3-N2-T6-E2-H3. The backbone genes of this strain (I2-R2-C2-M2-A3-N2-T6-E2-H3) are commonly found in rotavirus strains from artiodactyls such as cattle. Furthermore, phylogenetic analysis indicated that each of the 11 genes of strain DB2015-066 could be of artiodactyl (likely bovine) origin. Thus, strain DB2015-066 appeared to be derived from through zoonotic transmission of a bovine rotavirus strain. Of note, the VP7 gene of strain DB2015-066 was located in G10 lineage-6 together with ones of bovine and bovine-like rotavirus strains, away from the clusters comprising other G10P[14] strains in G10 lineage-2/4/5/9, suggesting the occurrence of independent bovine-to-human interspecies transmission events. Our observations provide important insights into the origins of rare G10P[14] strains, and into dynamic interactions between artiodactyl and human rotavirus strains.

Human rotavirus strains having the unconventional G4P[6] genotype have been sporadically identified in diarrheic patients in different parts of the world. However, the whole genome of only one human G4P[6] strain from Africa (central Africa) has been sequenced and analyzed, and thus the exact origin and evolutionary pattern of African G4P[6] strains remain to be elucidated. In this study, we characterized the full genome of an African G4P[6] strain (RVA/Human-wt/KEN/KCH148/2019/G4P[6]) identified in a stool specimen from a diarrheic child in Kenya. Full genome analysis of strain KCH148 revealed a unique Wa-like genogroup constellation: G4-P[6]-I1-R1-C1-M1-A1-N1-T7-E1-H1. NSP3 genotype T7 is commonly found in porcine rotavirus strains. Furthermore, phylogenetic analysis showed that 10 of the 11 genes of strain KCH148 (VP7, VP4, VP6, VP1-VP3, NSP1, and NSP3-NSP5) appeared to be of porcine origin, the remaining NSP2 gene appearing to be of human origin. Therefore, strain KCH148 was found to have a porcine rotavirus backbone and thus is likely to be of porcine origin. Furthermore, strain KCH148 is assumed to have been derived through interspecies transmission and reassortment events involving porcine and human rotavirus strains. To our knowledge, this is the first report on full genome-based characterization of a human G4P[6] strain from east Africa. Our observations demonstrated the diversity of human G4P[6] strains in Africa, and provide important insights into the origin and evolutionary pattern of zoonotic G4P[6] strains on the African continent.

Background This study was conducted to assess the transmissibility of rotavirus vaccine strains after rotavirus vaccination in a neonatal intensive care unit (NICU). Methods Pentavalent (RV5) or monovalent (RV1) rotavirus vaccine was administered to infants admitted to the NICU. Nineteen vaccinated infants and 49 unvaccinated infants whose beds were located in close proximity to the vaccinated infants were enrolled in this study. Dissemination and fecal shedding of vaccine viruses within the NICU were examined using real-time reverse transcription-polymerase chain reaction. Results Shedding of the vaccine strain was detected in all 19 vaccinated infants. RV5 virus shedding started 1 day after the first vaccination and persisted for 8 days after the first vaccination, and viral shedding terminated by day 5 after administration of the second RV5 dose. The kinetics of RV1 virus shedding differed among vaccinated infants. The duration of RV1 virus shedding was longer after the first vaccination than after the second vaccination. In contrast to the vaccinated infants, no vaccine virus genomes were detected in any of the stool samples collected from the 49 unvaccinated infants. Conclusions This study is direct evidence of no transmission of rotavirus vaccine strains between vaccinated infants and unvaccinated infants in close proximity within a NICU.

An unusual rotavirus strain with the G9P[23] genotype (RVA/Human-wt/THA/KKL-117/2014/G9P[23]) was identified in a stool specimen from a 10-month-old child hospitalized with severe diarrhoea. In this study, we sequenced and characterized the complete genome of strain KKL-117. On full-genomic analysis, strain KKL-117 was found to have the following genotype constellation: G9-P[23]-I5-R1-C1-M1-A8-N1-T1-E1-H1. The non-G/P genotype constellation of this strain (I5-R1-C1-M1-A8-N1-T1-E1-H1) is commonly shared with rotavirus strains from pigs. Furthermore, phylogenetic analysis indicated that each of the 11 genes of strain KKL-117 appeared to be of porcine origin. Our observations provide important insights into the dynamic interactions between human and porcine rotavirus strains.

The rotavirus-induced diarrhea of human and animal neonates is a major public health concern worldwide. Until recently, no effective therapy is available to specifically inactivate the rotavirion particles within the gut. Passive immunotherapy by oral administration of chicken egg yolk antibody (IgY) has emerged of late as a fresh alternative strategy to control infectious diseases of the alimentary tract and has been applied in the treatment of diarrhea due to rotavirus infection. The purpose of this concise review is to evaluate evidence on the properties and performance of anti-rotavirus immunoglobulin Y (IgY) for prevention and treatment of rotavirus diarrhea in human and animal neonates. A survey of relevant anti-rotavirus IgY basic studies and clinical trials among neonatal animals (since 1994-2015) and humans (since 1982-2015) have been reviewed and briefly summarized. Our analysis of a number of rotavirus investigations involving animal and human clinical trials revealed that anti-rotavirus IgY significantly reduced the severity of clinical manifestation of diarrhea among IgY-treated subjects relative to a corresponding control or placebo group. The accumulated information as a whole depicts oral IgY to be a safe and efficacious option for treatment of rotavirus diarrhea in neonates. There is however a clear need for more randomized, placebo controlled and double-blind trials with bigger sample size to further solidify and confirm claims of efficacy and safety in controlling diarrhea caused by rotavirus infection especially among human infants with health issues such as low birth weights or compromised immunity in whom it is most needed.

Rotaviruses (RVs) are highly important pathogens that cause severe diarrhea among infants and young children worldwide. The understanding of the molecular mechanisms underlying RV replication and pathogenesis has been hampered by the lack of an entirely plasmid-based reverse genetics system. In this study, we describe the recovery of recombinant RVs entirely from cloned cDNAs. The strategy requires coexpression of a small transmembrane protein that accelerates cell-to-cell fusion and vaccinia virus capping enzyme. We used this system to obtain insights into the process by which RV nonstructural protein NSP1 subverts host innate immune responses. By insertion into the NSP1 gene segment, we recovered recombinant viruses that encode split-green fluorescent protein–tagged NSP1 and NanoLuc luciferase. This technology will provide opportunities for studying RV biology and foster development of RV vaccines and therapeutics.

In Japan, monovalent and pentavalent rotavirus (RV) vaccines were approved in 2011 and 2012, respectively. To monitor changes in the RV genotypes before and after vaccine introduction, we performed a prospective observational study among children (＜ 5 years) with gastroenteritis who tested RV-positive on antigen rapid tests. Stool samples were collected from 3 different sites in Japan: Tsu City, Mie Prefecture; Kurashiki City, Okayama Prefecture; and Isumi City, Chiba Prefecture. RV genotypes were determined using reverse transcription-polymerase chain reaction. In Tsu City, G3P[8] was dominant (61.0-77.1%) before vaccine introduction, but decreased after introduction. Meanwhile, in an inverse proportion to the decrease in G3P[8], G1P[8] increased until the 2013/14 season, when a sudden predominance of G2P[4] (100%) occurred. A similar trend was observed in Kurashiki City in terms of the extent of reduction in G3P[8] and the emergence of G2P[4]. In Isumi City, G1P[8] was dominant (70.3%) before vaccine introduction, and G9P[8] became predominant (83.3%) in the 2013/14 season. To determine whether the genotype changes are attributable to vaccines or natural epidemiological changes, ongoing continuous monitoring of the RV genotypes is required.

The emergence of unusual DS-1-like intergenogroup reassortant rotaviruses with a bovine-like G8 genotype (DS-1-like G8P[8] strains) has been reported in several Asian countries. During the rotavirus surveillance program in Japan in 2017, a DS-1-like G8P[8] strain (RVA/Human-wt/JPN/SO1162/2017/G8P[8]) was identified in 43 rotavirus-positive stool samples. Strain SO1162 was shown to have a unique genotype constellation, including genes from both genogroup 1 and 2: G8-P[8]-I2-R2-C2-M2-A2-N2-T2-E2-H2. Phylogenetic analysis revealed that the VP1 gene of strain SO1162 appeared to have originated from DS-1-like G1P[8] strains from Thailand and Vietnam, while the remaining 10 genes were closely related to those of previously reported DS-1-like G8P[8] strains. Thus, SO1162 was suggested to be a reassortant strain that acquired the VP1 gene from Southeast Asian DS-1-like G1P[8] strains on the genetic background of co-circulating DS-1-like G8P[8] strains. Our findings provide important insights into the evolutionary dynamics of emerging DS-1-like G8P[8] strains.

The generation of recombinant group A rotaviruses (RVAs) entirely from cloned cDNAs has been described only for a single animal RVA strain, simian SA11-L2. We recently developed an optimized RVA reverse genetics system based on only RVA cDNAs (11-plasmid system), in which the concentration of cDNA plasmids containing the NSP2 and NSP5 genes is 3- or 5-fold increased in relation to that of the other plasmids. Based on this approach, we generated a recombinant human RVA (HuRVA)-based monoreassortant virus containing the VP4 gene of the simian SA11-L2 virus using the 11-plasmid system. In addition to this monoreassortant virus, authentic HuRVA (strain KU) was also generated with the 11-plasmid system with some modifications. Our results demonstrate that the 11-plasmid system involving just RVA cDNAs can be used for the generation of recombinant HuRVA and recombinant HuRVA-based reassortant viruses. IMPORTANCE Human group A rotavirus (HuRVA) is a leading pathogen causing severe diarrhea in young children worldwide. In this paper, we describe the generation of recombinant HuRVA (strain KU) from only 11 cloned cDNAs encoding the HuRVA genome by reverse genetics. The growth properties of the recombinant HuRVA were similar to those of the parental RVA, providing a powerful tool for better understanding of HuRVA replication and pathogenesis. Furthermore, the ability to manipulate the genome of HuRVAs “to order” will be useful for next-generation vaccine production for this medically important virus and for the engineering of clinical vectors expressing any foreign genes.

An unusual rotavirus strain with the G3P[10] genotype (RVA/Human-wt/THA/MS2015-1-0001/2015/G3P[10]) was identified in a stool sample from a hospitalized child aged 11 months with severe gastroenteritis in Thailand. In the current study, we sequenced and characterized the full genome of strain MS2015-1-0001. On full-genomic analysis, strain MS2015-1-0001 exhibited the following genotype configuration: G3-P[10]-I8-R3-C3-M3-A9-N3-T3-E3-H6, which is identical or closely related to those of bat and bat-like rotavirus strains (MYAS33-like). Furthermore, phylogenetic analysis revealed that all 11 genes of strain MS2015-1-0001 appeared to be of bat origin. Our findings provide evidence for bat-to-human interspecies transmission of rotaviruses and important insights into dynamic interactions between human and bat rotavirus strains.

Bovine group A rotavirus (RVA) is an important cause of acute diarrhea in calves worldwide. In order to obtain precise information on the origin and evolutionary dynamics of bovine RVA strains, we determined and analyzed the complete nucleotide sequences of the whole genomes of six archival bovine RVA strains; four Thai strains (RVA/Cow-tc/THA/A5-10/1988/G8P[1], RVA/Cow-tc/THA/A5-13/1988/G8P[1], RVA/Cow-tc/THA/61A/1989/G10P[5], and RVA/Cow-tc/THA/A44/1989/G10P[11]), one American strain (RVA/Cow-tc/USA/B223/1983/G10P[11]), and one Japanese strain (RVA/Cow-tc/JPN/KK3/1983/G10P[11]). On whole genomic analysis, the 11 gene segments of strains A5-10, A5-13, 61A, A44, B223, and KK3 were found to be considerably genetically diverse, but to share a conserved non-G/P genotype constellation except for the NSP1 gene (I2-R2-C2-M2-(A3/11/13/14)-N2-T6-E2-H3), which is commonly found in RVA strains from artiodactyls such as cattle. Furthermore, phylogenetic analysis revealed that most genes of the six strains were genetically related to bovine and bovine-like strains. Of note is that the VP1, VP3, and NSP2 genes of strains A5-10 and A5-13 exhibited a closer relationship with the cognate genes of human DS-1-like strains than those of other RVA strains. Furthermore, the VP6 genes of strains A5-10 and A5-13 appeared to be equally related to both human DS-1-like and bovine strains. Thus, strains A5-10 and A5-13 were suggested to be derived from the same evolutionary origin as human DS-1-like strains, and were assumed to be examples of bovine RVA strains that provide direct evidence for a close evolutionary relationship between bovine and human DS-1-like strains. Our findings will provide important insights into the origin of bovine RVA strains, and into evolutionary links between bovine and human RVA strains.

Porcine rotavirus C (RVC) is distributed throughout the world and is thought to be a pathogenic agent of diarrhea in piglets. Although, the VP7, VP4, and VP6 gene sequences of Japanese porcine RVCs are currently available, there is no whole-genome sequence data of Japanese RVC. Furthermore, only one to three sequences are available for porcine RVC VP1-VP3 and NSP1-NSP3 genes. Therefore, we determined nearly full-length whole-genome sequences of nine Japanese porcine RVCs from seven piglets with diarrhea and two healthy pigs and compared them with published RVC sequences from a database. The VP7 genes of two Japanese RVCs from healthy pigs were highly divergent from other known RVC strains and were provisionally classified as G12 and G13 based on the 86% nucleotide identity cut-off value. Pairwise sequence identity calculations and phylogenetic analyses revealed that candidate novel genotypes of porcine Japanese RVC were identified in the NSP1, NSP2 and NSP3 encoding genes, respectively. Furthermore, VP3 of Japanese porcine RVCs was shown to be closely related to human RVCs, suggesting a gene reassortment event between porcine and human RVCs and past interspecies transmission. The present study demonstrated that porcine RVCs show greater genetic diversity among strains than human and bovine RVCs.

Between July 2009 and June 2014, a total of 1,546 fecal specimens were collected from children

Bovine group A rotavirus (RVA) G8P[1] strains have been rarely detected in humans. Two Nigerian G8P[1] strains, HMG035 (RVA/Human-tc/NGA/HMG035/1999/G8P[1]) and NGRBg8 (RVA/Cow-tc/NGA/NGRBg8/1998/G8P[1]), were previously suggested to have the VP7, VP4, and NSP1 genes of bovine origin. In order to obtain precise information on the origin and evolution of these G8P[1] strains, the complete nucleotide sequences of the whole genomes of strains HMG035 and NGRBg8 were determined and analyzed in the present study. On whole genomic analysis, strains HMG035 and NGRBg8 were found to be very closely related to each other in all the 11 segments, and were found to have a bovine RVA-like genotype constellation (G8-P[1]-I2-R2-C2-M2-A11-N2-T6-E2-H3). Furthermore, on phylogenetic analysis, each of the 11 genes of strains HMG035 and NGRBg8 appeared to be of bovine origin. Thus, strains HMG035 and NGRBg8 were suggested to be derived from a common origin, and strain NGRBg8 was assumed to represent an example of bovine RVA strains that were transmitted to humans. Our findings provide clear evidence for direct bovine-to-human interspecies transmission of RVA strains.

Previous studies have demonstrated the transmission of rotavirus vaccine strains from vaccinated children to nonvaccinated siblings. We sought to fully elucidate the safety of rotavirus (RV) vaccination in closed contact circumstance, such as the foster home for future assessment of the vaccine safety in an neonatal intensive care unit. Stool samples were collected from 4 RV vaccinated (160 samples) and 23 unvaccinated (766 samples) infants. RV viral RNA loads were measured using real-time reverse transcription polymerase chain reaction (RT-PCR). RV vaccine strain RNA was persistently detected in stool samples collected from the four vaccine recipients and one unvaccinated infant, but not in the stool samples collected from the 22 other unvaccinated infants. The unvaccinated infant who tested positive for the RV vaccine strain was vaccinated prior to enrollment in this study. The quantitative real-time RT-PCR data revealed a peak viral RNA load 1 week after vaccination followed by a gradual decrease. The current study suggests that RV vaccination may be safe in a close contact environment because there was limited transmission from RV vaccinated to unvaccinated infants. J. Med. Virol. 89:79-84, 2017. © 2016 Wiley Periodicals, Inc.

A total of 1,141 rotavirus-negative stool specimens collected from diarrheic children in 4 distinct regions under sentinel surveillance in Thailand between 2006 and 2008 were examined by reverse-transcription (RT)-PCR for norovirus (NoV) and sapovirus (SaV). Three hundred 3 specimens (26.6%) were positive for NoV, with 34 and 269 belonging to genogroup I (GI) and genogroup II (GII), respectively. Twelve specimens (1.1%) were positive for SaV. Mixed infections were found in 5 specimens: 3 samples indicated the presence of both NoV GI and GII, and 2 samples indicated the presence of both NoV GII and SaV. Analysis of the monthly distribution of NoV and SaV revealed that NoV GII was clustered between September and February, while NoV GI was detected mainly in June and July; SaV was found in May, June, and July. In addition, 3 outbreaks of acute gastroenteritis at 2 junior high schools in Phichit and Bangkok, and at a university in Phitsanulok, Thailand in 2006 were found to have been caused by NoV infection. Sequence analysis of NoVs from sporadic cases and outbreaks showed them to be genotypes GII.4 and GII.6.