Distribution of norovirus and sapovirus genotypes with emergence of NoV GII.P16/GII.2 recombinant strains in Chiang Mai, Thailand.

Norovirus (NoV) and sapovirus (SaV) are recognized as the causative agents of acute gastroenteritis, and NoV is one of the leading pathogens reported worldwide. This study reports on the distribution of NoV and SaV genotypes in children hospitalized with acute gastroenteritis in Chiang Mai, Thailand, from January 2015 to February 2017. From a total of 843 stool samples, 170 (20.2%) and 16 (1.9%) were identified as having NoV and SaV infections, respectively. Two samples (0.2%) were positive for both NoV and SaV. Of these, NoV GII.4 (57.2%) was the dominant genotype, followed by GII.2, GII.3, GII.17, GII.6, GII.7, GII.13, GII.14, GII.15, GII.21, GI.6, and GI.5. Among the NoV GII.4 variants, Sydney 2012 was the dominant variant during the period 2015-2016, while the other variants detected in this study were Asia 2003 and New Orleans 2009. Interestingly, an increase of NoV GII.2 was observed in 2016 and 2017. Characterization of partial RNA-dependent RNA polymerase and VP1 nucleotide sequences of GII.2 strains revealed that more than half of the GII.2 strains circulating in 2016 and 2017 were recombinant strains of GII.P16/GII.2. For SaV, the majority of strains belonged to GI.1 (55.6%) and GI.2 (33.3%), while GII.5 accounted for 11.1%. In conclusion, this study demonstrates the diversity of NoV and SaV, and the emergence of NoV GII.P16/GII.2 recombinant strains in 2016 and 2017 in Chiang Mai, Thailand.

Noroviruses and sapoviruses associated with acute gastroenteritis in pediatric patients in Thailand: increased detection of recombinant norovirus GII.P16/GII.13 strains.

Enteric caliciviruses, including noroviruses (NoVs) and sapoviruses (SaVs), are recognized as important etiologic agents of acute gastroenteritis (AGE) with considerable genetic diversity. In order to gain an overview of the molecular epidemiology of human NoVs and SaVs in children hospitalized with AGE in Chiang Mai, Thailand, a total of 889 fecal specimens were collected from 2012 to 2014 and screened for NoVs and SaVs. Out of 889 fecal specimens, 154 (17.3%) and 6 (0.7%) were positive for NoV GII isolates and SaV, respectively. Among the NoV GII, 10 different genotypes were identified with genotype GII.4 being predominant (103 strains), followed by GII.3 (17 strains), GII.13 (13 strains), GII.1 (7 strains), GII.6 (7 strains), GII.7 (2 strains), GII.17 (2 strains), and one each of GII.2, GII.15, and GII.21 genotypes. It was observed that four variants of NoV GII.4 (Den Haag 2006b, Apeldoorn 2007, New Orleans 2009, Sydney 2012) were detected from 2012 to 2014. Analysis of partial nucleotide sequences of RdRp and VP1 of the emerging NoV GII.13 strains (9 of 13 strains) revealed that they all were GII.P16/GII.13 recombinants. In addition, four different genotypes of SaV, GI.1 (2 strains), GII.1 (1 strain), GII.4 (2 strains), and GIV.1 (1 strain) were detected. The data revealed heterogeneity and a highly dynamic distribution of NoV and SaV genotypes circulating in children admitted to hospitals with AGE in Chiang Mai, Thailand, during the period of 2012 to 2014.

Comparative Evaluation of Norovirus Infection in Children with Acute Gastroenteritis by Rapid Immunochromatographic Test, RT-PCR and Real-time RT-PCR.

Immunochromatographic (IC) test for norovirus detection is a rapid and simple detection method. This study evaluated the sensitivity and specificity of a recent version of R-Biopharm RIDA®QUICK Norovirus IC assay for norovirus detection in fecal specimens from children hospitalized with acute gastroenteritis. Fecal specimens were tested by IC kit in comparison with gold standard reverse transcription polymerase chain reaction (RT-PCR) and real-time RT-PCR. The IC kit showed high sensitivity and specificity comparable with PCR-based methods. None of false positive and false negative was found and the assay did not cross-react with other gastroenteritis viruses. The IC assay could detect genogroup I.5 (GI.5) and a wide range of genotypes in the GII noroviruses including GII.3, GII.4, GII.6, GII.7, GII.14, GII.15, GII.21, and also newly emerging GII.17 norovirus. In conclusion, this norovirus IC kit could be an alternative choice for rapid screening or a quick diagnostic tool for norovirus detection in fecal specimens of acute gastroenteritis patients.

Exploring the Wound Healing Potential of a Cuscuta chinensis Extract-Loaded Nanoemulsion-Based Gel.

Cuscuta chinensis (C. chinensis) presents many pharmacological activities, including antidiabetic effects, and antioxidant, anti-inflammatory, and antitumor properties. However, the wound care properties of this plant have not yet been reported. Therefore, this research aimed to evaluate the antioxidant, anti-inflammatory, and antibacterial activities of ethanol and ethyl acetate C. chinensis extracts. The phytochemical markers in the extracts were analyzed using high-performance liquid chromatography (HPLC). Then, the selected C. chinensis extract was developed into a nanoemulsion-based gel for wound care testing in rats. The results showed that both of the C. chinensis extracts exhibited antioxidant activity when tested using 2,2-Diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and lipid peroxidation inhibition assays. They reduced the expression of IL-1ß, IL-6, and TNF-α in RAW264.7 cells induced with lipopolysaccharide (LPS). The ethyl acetate extract also had antibacterial properties. Kaempferol was found in both extracts, whereas hyperoside was found only in the ethanol extract. These compounds were found to be related to the biological activities of the extracts, confirmed via molecular docking. The C. chinensis extract-loaded nanoemulsions had a small particle size, a narrow polydispersity index (PDI), and good stability. Furthermore, the C. chinensis extract-loaded nanoemulsion-based gel had a positive effect on wound healing, presenting a better percentage wound contraction Fucidin cream. In conclusion, this formulation has the potential for use as an alternative wound treatment and warrants further study in clinical trials.

Molecular detection and genetic characterization of Salivirus in environmental water in Thailand.

Salivirus (SalV), also known as klassevirus, is a newly discovered member of the Picornaviridae family, which has been proposed to be a potential causative agent of acute gastroenteritis. This study aimed to provide further insight into the currently limited epidemiological data of SalV in environmental water in Thailand, which could be a potential source of human infection. A total of 95 water samples were collected from six locations in Chiang Mai province, northern Thailand, between November 2016 and February 2018. The molecular screening for SalV was performed by the nested polymerase chain reaction. The SalV genotypes were then determined through nucleotide sequencing and phylogenetic analysis. SalV was detected in 31 out of the 95 (32.6%) water samples and all belonged to the A1 genotype, based on phylogenetic analysis of the 5'UTR and 3D regions. The SalV-A1 strains detected in the environmental water were closely related to the SalV-A1 detected in a patient with diarrhoea in the same geographical area, based on the nucleotide sequence identities of the 5'UTR and 3D regions ranging from 91 to 99% and 96-99%, respectively. This study reports the prevalence of SalV-A1 contamination in environmental water in Chiang Mai, Thailand.

Wide variety of recombinant strains of norovirus GII in pediatric patients hospitalized with acute gastroenteritis in Thailand during 2005 to 2015.

Norovirus (NoV) has been reported as being a common cause of acute gastroenteritis both in children and adults worldwide. Of the many variants, NoV GII.4 is the most predominant genotype. One of the mechanisms that drives the evolution and emergence of new variants of NoV is homologous recombination. This study describes the genetic recombination involved in cases of NoV GII detected in pediatric patients with acute gastroenteritis in Chiang Mai, Thailand during 2005 to 2015. From a total of 1938 stool samples, 3 (0.15%) were positive for NoV GI and 298 (15.38%) were identified as NoV GII. The genotypes detected in this study were GI.6, GI.14, GII.1, GII.2, GII.3, GII.4, GII.6, GII.7, GII.12, GII.13, GII.14, GII.15, GII.16, GII.17, GII.20, and GII.21. The NoV recombinant strains were verified by analysis of the partial sequence of ORF1 (RdRp)/ORF2 (capsid) junction. Phylogenetic analyses of partial ORF1 and ORF2 regions resulted in the identification of 21 (6.98%) NoV recombinant strains. Among these, 9 recombination patterns were detected in this study; GII.Pe/GII.4, GII.Pg/GII.1, GII.Pg/GII.12, GII.P7/GII.6, GII.P7/GII.14, GII.P12/GII.4, GII.P16/GII.2, GII.P16/GII.13, and GII.P21/GII.3. The findings demonstrated the wide variety of recombinant strains of NoV GII strains detected in pediatric patients admitted to the hospitals with acute gastroenteritis in Chiang Mai, Thailand during the past decade.

Molecular characterization of norovirus GII.17 detected in healthy adult, intussusception patient, and acute gastroenteritis children in Thailand.

Noroviruses (NoVs) have been recognized as a leading cause of sporadic cases and outbreaks of acute gastroenteritis in all age groups. During the surveillance of NoVs in Chiang Mai, Thailand, four cases of the novel GII.17 NoVs were sporadically detected by RT-PCR in 2014-2015. The first case of GII.17 was detected in a healthy adult who worked for a restaurant. The second case was found in a pediatric patient who admitted to the hospital with intussusception. The third and fourth cases were found in acute gastroenteritis children. Phylogenetic analysis clearly demonstrated that GII.17 NoVs detected in this study were genetically closely related with the novel GII.17 Kawasaki reference strains. These four GII.17 NoV positive specimens were also tested by two immunochromatographic test kits in order to evaluate the sensitivity for GII.17 NoV detection. The viral loads in those specimens were determined by real-time RT-PCR. The sensitivity of GII.17 NoV detection varies by individual test kits and also depending on the amount of the viruses contained in the fecal specimens. In summary, our study reported the detection of novel GII.17 NoVs in a wide range of subjects with and without diarrhea. Therefore, continued comprehensive screening and genetic molecular characterization of NoV strains circulating in this area need to be further investigated.