Novel hepatitis E like virus found in Swedish moose.

Area of Science:

• Virology
• Molecular Biology
• Public Health

Background:

• Hepatitis E virus (HEV) is a significant human pathogen.
• HEV is known to infect various mammalian species.
• Moose are a common game animal in Scandinavia.

Purpose of the Study:

• To perform molecular characterization of a novel HEV detected in a Swedish moose.
• To understand the genetic diversity and phylogenetic position of this new HEV strain.
• To assess potential implications for human health and HEV transmission.

Main Methods:

• Sequencing of a 5.1 kb amplicon covering partial ORF1, complete ORF2, ORF3, and poly(A) sequence.
• Comparative analysis of nucleotide and amino acid sequences with known HEV genotypes.
• Phylogenetic analysis to determine the evolutionary relationship of the novel HEV.

Main Results:

• The novel moose HEV is highly divergent from known HEV genotypes (37-63% nucleotide sequence similarity).
• The ORF3 sequence and ORF junction regions showed extensive divergence.
• Phylogenetic analysis placed the moose HEV on a distinct branch between known genotypes and other divergent animal HEVs.
• Two putative secondary stem-loop structures were retained but structurally altered.

Conclusions:

• The characterization of this highly divergent moose HEV expands our understanding of HEV diversity in mammalian hosts.
• The findings suggest potential unexplored HEV transmission pathways relevant to human health.
• Further research is necessary to determine the prevalence in moose and other species and evaluate human infection risks.