Kohji Mori

Multiplex real-time PCR assays for the detection of group C rotavirus, astrovirus, and Subgenus F adenovirus in stool specimens.

Group C rotavirus (GCRV), astrovirus (AstV), and adenovirus (subgenus F AdenoV) are etiologic agents of acute nonbacterial gastroenteritis, which often represents community outbreaks. For the efficient detection of GCRV, AstV, and subgenus F AdenoV in stool specimens, a multiplex real-time PCR assay was developed to detect these three viruses simultaneously, with high sensitivity and specificity. In total, 8404 clinical specimens were collected between April 2008 and March 2011 and tested for GCRV, AstV, and subgenus F AdenoV by the multiplex real-time PCR, as well as for norovirus (NoV), sapovirus (SaV), and group A rotavirus (GARV) by non-multiplex real-time PCR. Forty-one specimens were positive for GCRV, AstV, or subgenus F AdenoV, including 15 specimens that were also positive for NoV, SaV, or GARV. Multiple viruses were detected simultaneously in 29 out of 4596 (0.63%) specimens infected with at least one virus. The association rates of AstV and subgenus F AdenoV with other viruses were significantly higher than those of NoV, SaV, GARV, or GCRV.

Genomic analysis of the evolutionary lineage of Norovirus GII.4 from archival specimens during 1975–1987 in Tokyo

This study aimed to analyze NoV GII.4 sequences from archival specimens obtained during 1975–1987 by comparing them with reference sequences. The first NoV GII.P4_GII.4 sequence was identified in 1980. NoV GII.4 collected in 1970 had a GII.P1_GII.4 sequence. These results indicate that the GII.P4_GII.4 sequence may be the result of a recombination that might have occurred around 1980. Amino acid substitutions based on this replacement were mainly accumulated in the NTPase, p22, and RdRp regions. The emergence of GII.P4_GII.4 sequence is considered to have ended the major prevalence of NoV GII.4. J. Med. Virol. 89:363–367, 2017.

[Effects of hand hygiene on feline calicivirus inactivation and removal as norovirus surrogate treated with antiseptic hand rubbing, wet wipes, and functional water].

As a preventive action plan against gastroenteritis caused by the Norovirus (NV), we studied hand hygiene effects using with three hand rubbing products, four wet wipe products, and two functional water types using Feline Calicivirus as a Norovirus surrogate. After treatment using antiseptic hand rubbing products containing chlorhexidine, quaternary ammonium, and povidone-iodine, high inactivation detected by TCID50 was observed compared to products containing povidone-iodine, although no difference was seen in viral removal measured by the amount of viral genome copies in real-time-PCR. Among wet wipes soaked in chlorhexidine, quaternary ammonium, benzoic acid and PHMB, two groups showed viral inactivation and removal. Two products were more effective for functional water, viral decrease was seen in rinsing in running electrolyzed acid water and handwashing by soap. Results underscore the importance of selection in hand washing metheds (alternative soap and also) in preventing viral gastroenteritis.

Comparison of genetic characteristics in the evolution of Norovirus GII.4 and GII.17

The genetic characteristics of Norovirus GII.17 were evaluated. Phylogenetic analysis and comparisons of amino acid (Aa) substitutions and nonsynonymous (NS) substitutions/site/year were performed. The complete VP1 sequence of Tokyo/27‐3/1976 clustered independently with GII.P17_GII.17 strains. Aa substitutions were mainly accumulated in the P2 domain. NS substitutions/site/year for Tokyo/27‐3/1976 compared to Kawasaki323/2014 and Kawasaki308/2015 were 0.57 × 10−3 and 0.78 × 10−3, respectively; for GII.4 Sydney/NSW0514/2012 compared to CHDC2094/1974 and CHDC5191/1974 were 0.93 × 10−3 and 1.06 × 10−3, respectively. These findings imply that evolutionary diversity in the VP1 of GII.17 might be strictly constrained in contrast to that of GII.4.

Cloning and sequencing of the murine farnesyltransferase α-encoding cDNA from a cell line which expresses the human papillomavirus type-16 E6 gene

Using a differential hybridization technique, the murine farnesyltransferase alpha (FTA)-encoding cDNA was cloned from a mouse 10T1/2 cell line which expresses the human papillomavirus type 16 (HPV16) E6 gene. Sequence analysis revealed that the murine 1647-bp FTA cDNA encoded 377 amino acid (aa). The murine and human sequences showed 83.2% nucleotide and 92.6% aa sequence identity.

Detection of Norovirus in Swab Specimens of Restrooms and Kitchens Collected for Investigation of Suspected Food Poisoning Outbreaks in Tokyo

During 2015-2016, we examined norovirus (NoV) RNA in swab specimens collected for investigation of suspected food poisoning outbreaks in Tokyo by real-time RT-PCR. Of 1,726 swab samples, 65 (3.8%) were NoV-positive and all positive swab samples were derived from NoV-positive outbreaks. Swab specimens were positive in 41 of 181 (22.7%) NoV outbreaks, while no positive swabs were detected in NoV-negative outbreaks. PCR fragments amplified from 32 swabs were sequenced, and all of them displayed complete homology with sequences from clinical and food samples. Though the results of swabs may be useful for determining the causative agent and infection route in some outbreaks, there was no case in which the results of swabs alone could elucidate the cause of food poisoning. Swabs may be useful in food poisoning investigations, if the results are interpreted in conjunction with epidemiological findings and clinical data. Swab samples are often collected several days after an outbreak, and the influence of disinfection should be taken into consideration. In NoV outbreaks, 55 out of 640 (8.6%) restroom swab specimens were NoV-positive whereas six of 618 (1.0%) were positive among kitchen swab specimens. In the restroom, the toilet bowl (43.6%) showed the highest positive rate and next was the toilet seat (14.5%). Additionally, NoV was detected at various sites in the restroom, including doorknob and floor. Since NoV-positive swab specimens may suggest that sanitation management is not performed properly in the facility, swab results may be utilized as a basis for hygiene guidance.

Feasibility of viral dust infection via air movement and dispersion of dried viral particles from the floor.

The contributions of splash from vomiting and the dispersion of dried‐up virus from a contaminated floor surface to community gastroenteritis outbreaks caused by Norovirus (NoV) were evaluated, using Feline calicivirus (FCV) as an NoV surrogate. There was no difference in the size distribution of FCV‐containing particles around 0.75 µm) collected from a virus‐sprayed chamber 1 and 12 hr after nebulization. FCV clearly dispersed after hitting a floor surface contaminated with dried virus. These results suggest that NoV can likely form airborne droplet nuclei, and dust may be the main route of infection transmission. J. Med. Virol. 89:931–935, 2017.

HTLV-Iの母子感染初期にみられた血中IL-2およびsIL-2Rの増加について

In our laboratory, children born to women are known to be infected with Human T-cell Leukemia Virus type-1 (HTLV-I) have been followed using, detect of gene by PCR and antibody by Western Blot Assay (WB) and Immunofluorescence Assay (IFA) test from 1990 through 1996. Four children out of 123 delivery cases have been confirmed to be infected with HTLV-I. We analyzed the correlation between the concentration of cytokines (IL-2, sIL-2R, IFN-gamma) and HTLV-I infection. IL-2 and sIL-2R in sera increased after HTLV-I infection. There was no correlation between the concentration of IFN-gamma and HTLV-I infection. These result suggested that detection of IL-2 and sIL-2R might be the marker of HTLV-I infection.