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Published on: November 7, 2018
Short report: phylogenetically distinct hepatitis E viruses in Pakistan
H van Cuyck-Gandré1, H Y Zhang, S A Tsarev
1Department of Virus Diseases, Walter Reed Army Institute of Research, Washington, District of Columbia 20307-5100, USA.
Summary
Hepatitis E virus (HEV) strains in Pakistan show distinct genetic origins. Phylogenetic analysis reveals two geographically separate HEV clusters circulating within Pakistan, suggesting diverse transmission routes for this enterically transmitted hepatitis cause.
Area of Science:
- Virology
- Hepatology
- Epidemiology
Background:
- Hepatitis E virus (HEV) is a major cause of acute hepatitis in Asia.
- Phylogenetic studies suggest HEV transmission is geographically limited.
- HEV Sar-55, from a 1987 Pakistan outbreak, belongs to the Central-Asian cluster.
Purpose of the Study:
- To determine the genetic lineage of a second Pakistan HEV isolate.
- To compare HEV diversity within Pakistan.
Main Methods:
- Complete nucleotide sequencing of the Abbottabad HEV isolate.
- Phylogenetic analysis using statistical methods.
- Comparison with 15 other complete HEV sequences.
Main Results:
- The Abbottabad HEV isolate belongs to the South Asia cluster of the Asian sub-genotype.
- Sequence differences between the 1987 and 1988 Pakistan isolates were significant.
- Phylogenetic analysis confirmed distinct clustering of the two Pakistan HEV isolates.
Conclusions:
- Hepatitis E virus in Pakistan exhibits genetic diversity.
- Two distinct HEV origins likely circulate in Pakistan.
- This finding has implications for understanding HEV epidemiology and control in the region.
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