Zoonotic hepatitis E: animal reservoirs and foodborne transmissions
Résumé
In Western countries, the concept of zoonotic hepatitis E has emerged two decades ago following the discovery of animal strains of hepatitis E virus (HEV). In particular, HEV strains circulating in domestic and wild pigs are genetically very similar to strains identified in human cases. Contamination of pork products (liver, sausages, pies…) by HEV is now well described and the consumption of raw or undercooked contaminated meat or meat products are known to transmit. Hence, HEV can be a zoonotic foodborne pathogen. Recent advances in the identification of HEV strains in other animal species (rabbit, camel, rat…) and their detection in human have confirmed that several HEV member of the Hepeviridae family can be zoonotic. Thus, other food products such as meat or milk from other animal species (camel) may also represent significant risks. Possible HEV zoonotic reservoirs in ovine or bovine species are still debated. Further investigations are needed to screen for the presence of infectious HEV in larger variety of animal species and derived food products. HEV from infected human or animal faeces can be released in effluents (waste water treatment plans, slurry …) leading to contamination of the environment. Hence, food of non-animal origin consumed raw, such as crops, berries and bivalve molluscs, could vehicle HEV. Environmental contamination may also lead to accidental water borne Hepatitis E in developed countries. An exhaustive understanding of HEV animal reservoirs and transmission routes is essential to control and prevent efficiently this disease with increasing public health concern.