Hepatitis E Virus: Animal Models and Zoonosis.

Hepatitis E virus (HEV) is an important human pathogen that historically has been difficult to study. Limited levels of replication in vitro hindered our understanding of the viral life cycle. Sporadic and low-level virus shedding, lack of standardized detection methods, and subclinical infections made the development of animal models difficult. Better diagnostic techniques and understanding of the virus increased our ability to identify and characterize animal strains and animals that are amenable to model human-relevant infection. These advances are translating into the development of useful HEV animal models so that some of the greatest concerns associated with HEV infection, including host immunology, chronic infection, severe pregnancy mortality, and extrahepatic manifestations, can now be studied. Continued development of these animal models will be instrumental in understanding the many complex questions associated with HEV infection and for assessing therapeutics and prevention strategies to minimize HEV becoming a greater risk to the human population.