Epsilon Archive for Student Projects

Abstract

Hepatitis E virus, HEV, is a frequent causative agent behind, especially waterborne, infections in developing countries such as India. However, during the last years the number of non-travel-associated infections in industrialised countries, for example US, Germany and Sweden, has increased. The symptoms vary from mild with nausea to icterus and it can even be lethal. There are four different genotypes of HEV and many studies consider HEV infection to be a zoonosis. Scientists have by using phylogenetic analyses found great genetic similarity between strains isolated from humans, pigs and food, such as pork and liver, especially among viruses belonging to genotype 3. Genotype 3 has been shown to be involved in outbreaks linked to consumption of poor cooked meat. Studies have shown cross species infection, where pigs have been infected with human HEV strains and nonhuman apes infected with swine HEV strains. The prevalence of antibodies among people in many industrialized countries is higher than earlier assumed. In addition to this, the levels of anti-HEV from swine and anti-HEV from humans, that means antibodies against both virus strains from animals and humans, among blood donators in USA are the same and veterinarians working with swine have higher levels of both. Humans and animals can be infected and secrete virus without having any symptoms and thus act as reservoirs for the virus.