Hepatitis E Virus

Hepatitis E virus (HEV) is a small non-enveloped virus, which is transmitted via the fecal-oral route. The strains which infect humans predominantly belong to genotypes 1–4. HEV strains cause a large number of infections each year. The clinical symptoms of HEV infection are similar to those of hepatitis A, although genotypes 1 and 4 can cause mortality in pregnant women. Genotypes 3 and 4 can be found also in animals. Due to their presence in domestic pigs, there is a significant potential for these genotypes, especially 3, to be transmitted zoonotically. Zoonotic transmission has been shown to occur, particularly through the consumption of undercooked pork products. The precise conditions for inactivation of infectious HEV during cooking have not yet been identified, and there is a risk of undercooking pork products and therefore allowing infectious HEV to survive. Other foodstuffs such as shellfish and fresh produce may also be at some risk of becoming contaminated with HEV, through contamination of water courses with pig manure. Methods for detection of HEV in foods are being developed, and await standardization.