Recent knowledge on hepatitis E virus in Suidae reservoirs and transmission routes to human

Nicole Pavio,Reimar Johne,Virginie Doceul,Eugénie Bagdassarian

doi:10.1186/s13567-017-0483-9

Abstract

Hepatitis E virus (HEV) causes self-limiting acute hepatitis in humans that can eventually result in acute liver failures or progress to chronic infections. While in tropical and sub-tropical areas, HEV infections are associated with important waterborne epidemics, in Northern countries, HEV infections are autochthonous with a zoonotic origin. In the past decade, it has become clear that certain HEV genotypes are zoonotic and that swine, and more generally Suidae, are the main reservoir. Zoonotic transmissions of the virus may occur via direct contact with infected pigs, wild boars or consumption of contaminated meat. This review describes the current knowledge on domestic and wild Suidae as reservoirs of HEV and the evidence of the different routes of HEV transmission between these animals and humans.

Highlights

2 Suidae reservoirs2.1 Domestic swine 2.1.1 Hepatitis E virus (HEV) infection in domestic pigs 2.1.2 Risk factors associated with HEV infection within pig farms2.2 Wild fauna 2.3 H EV transmission between domestic and wildSuidae 3 HEV in food products from Suidae and deer 4 Contact exposure with Suidae
1 Introduction Hepatitis E virus (HEV) infection is highly prevalent in human worldwide, with more than 20 million infections each year (WHO)
5 Conclusions In the past decade, many studies have provided evidence that Suidae are the main reservoir of zoonotic HEV and that the virus is endemic in pig farms worldwide

Summary

Introduction

Hepatitis E virus (HEV) infection is highly prevalent in human worldwide, with more than 20 million infections each year (WHO). This review aims at presenting the recent data on Suidae reservoirs, cross-contaminations between wild and domestic pigs and on vehicles of HEV exposure through contacts or consumption of food products from infected animals. The highest detection rates and amounts of HEV RNA are found in the liver, whereas other organs show lower detection rates as well as lower HEV RNA concentrations In these experimental models, several inoculation routes were used: intravenous, oral route and contact with inoculated animals. Only few studies were conducted at slaughterhouse, on small sample size, to investigate the presence of HEV RNA in the organs of naturally infected pigs. The virus is mainly excreted fecally in pigs, leading to an accumulation of HEV in the environment of infected livestock Both contact between individuals and environmental exposure can play a role in HEV transmission. According to the results of this study, the movements of trucks and utility vehicles might play an important role in HEV dissemination on a slaughterhouse site and throughout an entire network [31]

Risk factors associated with HEV infection within pig farms

Findings

Conclusions