Prevalence and genotype distribution of group A rotavirus circulating in Shanxi Province, China during 2015-2019

BACKGROUND

Group A rotavirus (RVA), despite being a leading cause of gastroenteritis in infants and young children, is less studied in Shanxi Province, China. The current study was conducted to determine the prevalence and genetic characterization of RVA in hospitalized children younger than 10 years of age with the diagnosis of acute gastroenteritis in Shanxi Province, China.

METHODS

A hospital-based active surveillance of rotavirus gastroenteritis was conducted at Children's Hospital of Shanxi from Jan 1, 2015, through Dec 31, 2019. Rotavirus was detected in stool samples by real-time quantitative reverse transcription PCR (qRT-PCR). G- and P-genotypes were determined by reverse transcription PCR (RT-PCR) and nucleotide sequencing.

RESULTS

A total of 961 children younger than 10 years of age was enrolled over the study period, of whom 183 (19.0%) were positive for RVA. The highest RVA-infection frequency (23.7%) was found among children aged 12-23 months, and the seasonal peak was in December. G9P[8] was most prevalent (76.0%), followed by G3P[8] (7.1%), G2P[4] (3.3%), G1P[8] (0.5%) and G9P[4] (0.5%).

CONCLUSIONS

These results report for the first time that RVA was one of the main causes of severe infectious gastroenteritis in children, and a high proportion of G9P[8] strains circulating in most areas of Shanxi Province. While the protective efficacy of the rotavirus vaccines has been demonstrated against G9P[8] strains, our results highlight that the dominant strains have not been effectively controlled in China.

Characterization of a genetically heterogeneous porcine rotavirus C, and other viruses present in the fecal virome of a non-diarrheic Belgian piglet

Next-generation sequencing (NGS) technologies are becoming increasingly accessible, leading to an expanded interest in the composition of the porcine enteric virome. In the present study, the fecal virome of a non-diarrheic Belgian piglet was determined. Although the virome of only a single piglet was analyzed, some interesting data were obtained, including the second complete genome of a pig group C rotavirus (RVC). This Belgian strain was only distantly related to the only other completely characterized pig RVC strain, Cowden. Its relatedness to RVC strains from other host species was also analyzed and the porcine strain found in our study was only distantly related to RVCs detected in humans and cows. The gene encoding the outer capsid protein VP7 belonged to the rare porcine G3 genotype, which might be serologically distinct from most other pig RVC strains. A putative novel RVC VP6 genotype was identified as well. A group A rotavirus strain also present in this fecal sample contained the rare pig genotype combination G11P[27], but was only partially characterized. Typical pig RVA genotypes I5, A8, and T7 were found for the viral proteins VP6, NSP1, and NSP3, respectively. Interestingly, the fecal virome of the piglet also contained an astrovirus and an enterovirus, of which the complete genomes were characterized. Results of the current study indicate that many viruses may be present simultaneously in fecal samples of non-diarrheic piglets. In this study, these viruses could not be directly associated with any disease, but still they might have had a potential subclinical impact on pig growth performance. The fast evolution of NGS will be a powerful tool for future diagnostics in veterinary practice. Its application will certainly lead to better insights into the relevance of many (sub)clinical enteric viral infections, that may have remained unnoticed using traditional diagnostic techniques. This will stimulate the development of new and durable prophylactic measures to improve pig health and production.

•

The virome of a non-diarrheic Belgian piglet was determined.

•

Porcine group C and A rotaviruses, and an astrovirus and enterovirus were found.

•

The second complete genome of a pig group C rotavirus was fully characterized.

•

The Belgian rotavirus C strain was only distantly related to pig strain Cowden.

•

A putative novel genotype of VP6 of the RVC strains was detected.