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Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Virology. Nov 12, 2015; 4(4): 343-355
Published online Nov 12, 2015. doi: 10.5501/wjv.v4.i4.343
Hepatitis E virus infection: Epidemiology and treatment implications
Ga Young Lee, Kittiyod Poovorawan, Duangnapa Intharasongkroh, Pattaratida Sa-nguanmoo, Sompong Vongpunsawad, Chintana Chirathaworn, Yong Poovorawan
Ga Young Lee, Kittiyod Poovorawan, Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
Duangnapa Intharasongkroh, Pattaratida Sa-nguanmoo, Sompong Vongpunsawad, Yong Poovorawan, Center of Excellence in Clinical Virology, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
Duangnapa Intharasongkroh, National Blood Centre, Thai Red Cross Society, Bangkok 10330, Thailand
Chintana Chirathaworn, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
Author contributions: Poovorawan Y designed and outlined the research; Lee GY, Poovorawan K, Intharasongkroh D, Sa-nguanmoo P, Vongpunsawad S and Chirathaworn C wrote the paper.
Supported by The National Research University Project, Office of Higher Education Commission, Nos. WCU001-HR-57, WCU007-HR-57, and WCU-58-006-HR; The National Research Council of Thailand (NRCT); The Research Chair Grant from the National Science and Technology Development Agency, Chulalongkorn University Centenary Academic Development Project, No. CU56-HR01; Ratchadaphiseksomphot Endowment Fund of Chulalongkorn University, No. RES560530093; The Outstanding Professor of Thailand Research Fund, No. DPG5480002; The Doctoral Degree Chulalongkorn University 100th Year Birthday Anniversary to Duangnapa Intharasongkroh; and The Rachadapisek Sompote Fund of Chulalongkorn University for Postdoctoral Fellowship to Pattaratida Sa-nguanmoo.
Conflict-of-interest statement: The authors declare no conflicts of interests for this article.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Yong Poovorawan, MD, Professor, Center of Excellence in Clinical Virology, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Rama IV Rd, Bangkok 10330, Thailand. yong.p@chula.ac.th
Telephone: +66-2-2564909 Fax: +66-2-2564929
Received: May 25, 2015
Peer-review started: May 26, 2015
First decision: July 27, 2015
Revised: August 6, 2015
Accepted: September 16, 2015
Article in press: September 18, 2015
Published online: November 12, 2015
Abstract

Hepatitis E virus (HEV) infection is now established as an emerging enteric viral hepatitis. Standard treatments in acute and chronic hepatitis E remain to be established. This study undertakes a review of the epidemiology, treatment implication and vaccine prevention from published literature. HEV infection is a worldwide public health problem and can cause acute and chronic hepatitis E. HEV genotypes 1 and 2 are primarily found in developing countries due to waterborne transmission, while the zoonotic potential of genotypes 3 and 4 affects mostly industrialized countries. An awareness of HEV transmission through blood donation, especially in the immunocompromised and solid organ transplant patients, merits an effective anti-viral therapy. There are currently no clear indications for the treatment of acute hepatitis E. Despite concerns for side effects, ribavirin monotherapy or in combination with pegylated interferon alpha for at least 3 mo appeared to show significant efficacy in the treatment of chronic hepatitis E. However, there are no available treatment options for specific patient population groups, such as women who are pregnant. Vaccination and screening of HEV in blood donors are currently a global priority in managing infection. New strategies for the treatment and control of hepatitis E are required for both acute and chronic infections, such as prophylactic use of medications, controlling large outbreaks, and finding acceptable antiviral therapy for pregnant women and other patient groups for whom the current options of treatment are not viable.

Keywords: Treatments, Blood donors, Adverse effects, Vaccination, Pegylated-interferon, Ribavirin, Hepatitis E

Core tip: Hepatitis E virus (HEV) infection affects individuals in both industrialized and developing countries and can cause acute and chronic hepatitis E. HEV genotypes 1 and 2 are primarily found in developing countries due to waterborne transmission, while the zoonotic potential of genotypes 3 and 4 affects mostly industrialized countries. An awareness of HEV transmission through blood donation, especially in the immunocompromised and solid organ transplant patients, merits an effective anti-viral therapy. The current treatment for HEV infection involving ribavirin and pegylated interferon-α therapy has shown limited efficacy. Although not widely used, an HEV vaccine is available for immunization in China.