Dataset Information

Identification of a Putative Novel Genotype of Avian Hepatitis E Virus from Apparently Healthy Chickens in Southwestern Nigeria.

ABSTRACT: Avian hepatitis E virus (aHEV) is the major etiological agent of hepatitis-splenomegaly syndrome (HSS), big liver and spleen disease (BLSD), and hepatic rupture hemorrhage syndrome (HRHS) in chickens. Infections with aHEV cause a significant decrease in egg production and increased mortality in chickens worldwide. However, studies on the prevalence of aHEV in Nigeria are scarce. In this study, serum (n = 88) and fecal samples (n = 110) obtained from apparently healthy layer chickens from three states in southwestern Nigeria were analyzed by nested reverse transcription-polymerase chain reaction (nRT-PCR) targeting the helicase and capsid gene for the presence of aHEV. Avian HEV was detected in 12.5% (n = 11/88) of serum samples and 9.1% (n = 10/110) of fecal samples tested. Phylogenetic analysis showed that five of the twelve identified aHEV sequences belonged to genotype 2. The remaining seven sequences were only distantly related to other known aHEV isolates. After amplification of the near-complete ORF2 fragment (1618 bp) and part of the ORF1 (582 bp) of isolate YF40_aHEV_NG phylogenetic analysis revealed a nucleotide sequence identity between 79.0 and 82.6% and 80.1 and 83.5%, respectively, to other known aHEV strains, indicating that the Nigerian isolate YF40_aHEV_NG belongs to a novel aHEV genotype. This is the first report of co-circulation of aHEV genotypes in chickens in Nigeria.

SUBMITTER: Osamudiamen FT

PROVIDER: S-EPMC8224330 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Hepatitis E virus (HEV) is a viral pathogen transmitted by the fecal-oral route and is a major cause of waterborne acute hepatitis in many developing countries. In addition to infecting humans, HEV has been identified in swine, wild boars, rabbits and other mammals; with swine and wild boars being main reservoirs for zoonotic transmission of HEV. There are four major HEV genotypes known to infect humans; genotypes 1 (HEV-1) and 2 (HEV-2) are restricted to humans, and genotypes 3 (HEV-3) and 4 (HEV-4) are zoonotic. Herein, three human HEV strains originating in France were sequenced and near full-length genomes were characterized. Phylogenetic analysis showed that two strains were genotype 3 and closely grouped (a 100% bootstrap value) with subtype 3i reference strains. In percent nucleotide identities, these two strains were 94% identical to each other, 90-93% identical to subtype 3i strains, 82-86% identical to other HEV-3, and 77-79% identical to rabbit HEV strains excluding the two divergent strains KJ013414 and KJ013415 (74%); these two strains were less than 77% identical to strains of HEV genotypes 1, 2 and 4. The third strain was found distinct from any known HEV strains in the database, and located between the clusters of HEV-3 and rabbit HEV strains. This unique strain was 74-75% identical to HEV-1, 73% to HEV-2, 81-82% to HEV-3, 77-79% to rabbit HEV again excluding the two divergent strains KJ013414 and KJ013415 (74%), and 74-75% to HEV-4, suggesting a novel unclassified strain associated with HEV-3 and rabbit HEV. SimPlot and BootScan analyses revealed a putative recombination of HEV-3 and rabbit HEV sequences at four breakpoints. Phylogenetic trees of the five fragments of the genome confirmed the presence of two HEV-3 derived and three unclassified sequences. Analyses of the amino acid sequences of the three open reading frames (ORF1-3) encoded proteins of these three novel strains showed that some amino acid residues specific to rabbit HEV strains were found solely in this unclassified strain but not in the two newly identified genotype 3i strains. The results obtained by SimPlots, BootScans, phylogenetic analyses, and amino acid sequence comparisons in this study all together appear to suggest that this novel unclassified strain is likely carrying a mosaic genome derived from HEV-3 and rabbit HEV sequences, and is thus designated as a putative genotype 3/rabbit HEV recombinant.

Dataset Information

Identification of a Putative Novel Genotype of Avian Hepatitis E Virus from Apparently Healthy Chickens in Southwestern Nigeria.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets