Seroprevalence of Hepatitis E Virus in Human and Pigs in Pig Farms from Guangdong Province,Southern China

Hepatitis E is caused by hepatitis E virus （HEV）, which has been classified into four genotypes. Genotypes 3 and 4 are regarded as zoonotic pathogens. Accumulating researches indicate that genotype 4 is the main HEV strain circulating in China, and there are high levels of seropositive pigs and human in some provinces of China. In this study, serum samples from pigs and from human occupationally exposed to pigs were obtained from pig farms in Guangdong Province, in subtropical southern China, in order to investigate for the first time the prevalence of anti-HEV immunoglobulin G （IgG） in the region. Antibodies against HEV were detected by Enzyme-Linked Immunosorbent Assay （ELISA） using a commercially marketed kit. The results showed that high numbers of pigs （74/94; 78.7%） and human （50/94; 53.2%） from three pig farms in Guangdong Province were positive for anti-HEV IgG. The correlation coefficient relating the prevalence in pigs and human on different farms was 0.920. The seropositive rate in males （human） was 48.8% （20/41） and that in females was 47.7% （9/19）, which showed no statistically significant difference. These data indicated that there was a high prevalence of anti-HEV antibodies in pigs and in human with occupational exposure to pigs. The risk of infection with HEV in both human and pigs in Guangdong Province appeared to be age-dependent, to a certain extent. This study provided basic data for further researches on HEV and was a reminder that more attention should be paid to HEV infection both in pigs and workers on pig farms in the study region.

Identification and genetic characterization of bovine hepacivirus in China:A large scale epidemiological study

Bovine hepacivirus(BovHepV)is a novel virus that was recently discovered in Ghana and Germany in 2015.Until now,this virus has been identified in cattle population worldwide and is classified into subtypes A-G.To fully understand the epidemic situation and genetic characteristic of BovHepV in China,a total of 612 cattle serum samples were collected from 20 farms in seven provinces and municipality in China between 2018 and 2020 and were tested for the presence of BovHepV RNA via semi-nested PCR.The results demonstrated that 49(8.0%)samples were BovHepV RNA-positive.It is noted that BovHepV infection in yak was confirmed for the first time.BovHepV was detected in all the seven provinces,with the positive rate ranging from 3.1%to 13.3%,which indicates a wide geographical distribution pattern of BovHepV in China.Sequencing results revealed that 5'UTR of the 49 field BovHepV strains have a nucleotide similarity of 96.3%-100%between each other and 93.9%-100%with previously reported BovHepV strains.In addition,genetic analysis identified five critical nucleotide sites in 5'UTR to distinguish different subtypes,which was further verified by genomic sequencing and nucleotide similarity analysis.All the 49 Chinese field BovHepV strains were classified into subtype G and this subtype is only determined in cattle in China currently.This study will provide insights for us to better understand the epidemiology and genetic diversity of BovHepV.

Novel HCV-Like Virus Detected in Avian Livers in Southern China and Its Implications for Natural Recombination Events

Dear Editor,Hepacivirus C virus(HCV)is a major cause of liver disease in human,which is estimated to infect 2%–3%of the world’s population and has resulted in a high global health burden.HCV was first discovered in 1989,and was the sole member of the Hepacivirus genus before 2011.Recently,genetically-diverse HCV-like viruses have been independently determined in a number of animal species.