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Hepatitis E Virus Genotypes and Evolution: Emergence of Camel Hepatitis E Variants
Siddharth Sridhar1, Jade L L Teng2,3,4,5, Tsz-Ho Chiu6
1Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China. sid8998@gmail.com.
International Journal of Molecular Sciences
|April 21, 2017
Summary
Hepatitis E virus (HEV) taxonomy is evolving rapidly, with new genotypes discovered in camels. These findings highlight the expanding significance of zoonotic HEV in human health and underscore the need for ongoing research.
Area of Science:
- Virology
- Molecular Taxonomy
- Epidemiology
Background:
- Hepatitis E virus (HEV) is a significant global cause of viral hepatitis.
- Zoonotic HEV strains are increasingly recognized as a cause of chronic hepatitis in immunocompromised individuals.
- Advances in sequencing have led to significant revisions in the taxonomy of the Hepeviridae family.
Purpose of the Study:
- To review recent advancements in Hepatitis E virus molecular taxonomy, epidemiology, and evolution.
- To highlight the discovery of novel camel HEV genotypes as a case study for taxonomic changes.
- To underscore the expanding significance of HEV in human health.
Main Methods:
- Review of recent scientific literature on HEV.
- Analysis of molecular taxonomy and sequence data.
- Epidemiological data interpretation.
Main Results:
- The Hepeviridae family is now classified into two genera: Orthohepevirus (terrestrial vertebrates) and Piscihepevirus (fish).
- Orthohepevirus A, which infects humans, now comprises eight genotypes (HEV1-HEV8) with diverse host ranges.
- Novel genotypes HEV7 and HEV8 were identified in dromedary and Bactrian camels, respectively, with HEV7 demonstrating rapid significance to human health.
Conclusions:
- The molecular taxonomy of HEV is dynamic, with ongoing discoveries reshaping our understanding of its diversity and evolution.
- The identification of novel zoonotic HEV genotypes, particularly in camels, emphasizes the importance of interspecies transmission and public health surveillance.
- Continued research into HEV epidemiology and evolution is crucial for managing its impact on global health.
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