Distribution of Human Sapovirus Strain Genotypes over the Last Four Decades in Japan: a Global Perspective.

Sapovirus (SaV) infections are a public health problem because they cause acute gastroenteritis in humans of all ages, both sporadically and as outbreaks. However, only a limited amount of SaV sequence information, especially whole-genome sequences for all the SaV genotypes, is publicly available. Therefore, in this study, we determined the full/near-full-length genomic sequences of 138 SaVs from the 2001 to 2015 seasons in 13 prefectures across Japan.

Evolutionary Analysis of the and RNA-Dependent RNA Polymerase Regions of Human Norovirus GII.P17-GII.17 in 2013-2017.

Human norovirus (HuNoV) GII.P17-GII.17 (Kawasaki2014 variant) reportedly emerged in 2014 and caused gastroenteritis outbreaks worldwide.

Molecular Evolution of the RNA-Dependent RNA Polymerase and Capsid Genes of Human Norovirus Genotype GII.2 in Japan during 2004-2015.

The RNA-dependent RNA polymerase () and capsid () genes of 51 GII.2 human norovirus (HuNoV) strains collected during the period of 2004-2015 in Japan were analyzed. Full-length analyses of the genes were performed using next-generation sequencing.

Detection of gastroenteritis viruses among pediatric patients in Hiroshima Prefecture, Japan, between 2006 and 2013 using multiplex reverse transcription PCR-based assays involving fluorescent dye-labeled primers.

Multiplex reverse transcription (RT)-polymerase chain reaction (PCR)-based assays involving fluorescent dye-labeled primers were modified to detect 10 types of gastroenteritis viruses by adding two further assays to a previously developed assay. Then, these assays were applied to clinical samples, which were collected between January 2006 and December 2013. All 10 types of viruses were effectively detected in the multiplex RT-PCR-based assays.

Molecular evolution of the capsid gene in human norovirus genogroup II.

Capsid protein of norovirus genogroup II (GII) plays crucial roles in host infection. Although studies on capsid gene evolution have been conducted for a few genotypes of norovirus, the molecular evolution of norovirus GII is not well understood. Here we report the molecular evolution of all GII genotypes, using various bioinformatics techniques.

Genetic analysis of human rotavirus C: The appearance of Indian-Bangladeshi strain in Far East Asian countries.

Rotaviruses C (RVCs) circulate worldwide as an enteric pathogen in both humans and animals. Most studies of their genetic diversity focus on the VP7 and VP4 genes, but the complete genomes of 18 human RVCs have been described in independent studies. The genetic background of the Far East Asian RVCs is different than other human RVCs that were found in India and Bangladesh.

Clinical evaluation of a bioluminescent enzyme immunoassay for detecting norovirus in fecal specimens from patients with acute gastroenteritis.

Noroviruses (NoVs), which belong to the family Caliciviridae, are major causative agents of acute gastroenteritis worldwide. Thus, rapid and highly sensitive assays for detecting NoVs are required. Recently, a bioluminescent enzyme immunoassay (BLEIA) for detecting NoVs in fecal specimens was developed.

Simple method for differentiating measles vaccine from wild-type strains using loop-mediated isothermal amplification.

Because of increasing measles vaccine coverage, the proportion of patients with modified measles has been increasing. Such patients have low-grade fever with very mild eruptions similar to vaccine-related adverse events. Differentiation between these two pathogenic conditions is required to improve the quality of laboratory-based measles surveillance.

Detection of norovirus, sapovirus, and human astrovirus in fecal specimens using a multiplex reverse transcription-PCR with fluorescent dye-labeled primers.

We applied a multiplex reverse transcription-PCR with fluorescent dye-labeled primers (fluorescent multiplex RT-PCR) for noroviruses (NoV), sapovirus (SaV), and human astrovirus (HAstV) to diagnose 71 outbreaks of acute gastroenteritis during July 2007 and May 2010 in Hiroshima prefecture. In this assay, the green, red, yellow, and blue fluorescence for NoV genogroup I, NoV genogroup II, SaV, and HAstV, respectively, were indicated on an agarose gel under ultraviolet light. In 61 virus-positive outbreaks confirmed by fluorescent multiplex RT-PCR, detection rates of outbreaks for NoVs, SaV, and HAstV were 96.

Simultaneous detection of virulence factors from a colony in diarrheagenic Escherichia coli by a multiplex PCR assay with Alexa Fluor-labeled primers.

We have developed simultaneous detection of eight genes associated with the five categories of diarrheagenic Escherichia coli by the multiplex PCR assay with Alexa Fluor-labeled primers. This assay can easily distinguish eight genes based on the size and color of amplified products without gel staining.

[Rapid detection of novel influenza A virus and seasonal influenza A (H1N1, H3N2) viruses by reverse transcription-loop-mediated isothermal amplification (RT-LAMP)].

Reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assay we developed detects novel influenza A (H1N1) of swine origin and seasonal influenza A (H1N1 and H3N2) viruses. Individual primer sets targeting the HA gene for novel H1N1, H1N1, and H3N2 were newly designed to specifically detect these subtypes. No cross-reactions occurred among novel H1N1, H1N1, and H3N2, and 7 respiratory viruses-influenza B virus, influenza C virus, adenovirus, respiratory syncytial virus, metapneumovirus, parainfluenza virus, and rhinovirus-had no reaction to 3 RT-LAMP assays.

Transition of genotypes associated with norovirus gastroenteritis outbreaks in a limited area of Japan, Hiroshima Prefecture, during eight epidemic seasons.

The transition of genotypes implicated in 102 NoV gastroenteritis outbreaks in Hiroshima Prefecture, Japan, during eight epidemic seasons was investigated. Eighteen genotypes were implicated in the outbreaks, with the chronological characteristics as in GII.3, GII.