Hepatitis E Virus: Foodborne, Waterborne and Zoonotic Transmission

Abstract

Hepatitis E virus (HEV) is responsible for epidemics and endemics of acute hepatitis in humans, mainly through waterborne, foodborne, and zoonotic transmission routes. HEV is a single-stranded, positive-sense RNA virus classified in the family Hepeviridae and encompasses four known Genotypes (1–4), at least two new putative genotypes of mammalian HEV, and one floating genus of avian HEV. Genotypes 1 and 2 HEVs only affect humans, while Genotypes 3 and 4 are zoonotic and responsible for sporadic and autochthonous infections in both humans and several other animal species worldwide. HEV has an ever-expanding host range and has been identified in numerous animal species. Swine serve as a reservoir species for HEV transmission to humans; however, it is likely that other animal species may also act as reservoirs. HEV poses an important public health concern with cases of the disease definitively linked to handling of infected pigs, consumption of raw and undercooked animal meats, and animal manure contamination of drinking or irrigation water. Infectious HEV has been identified in numerous sources of concern including animal feces, sewage water, inadequately-treated water, contaminated shellfish and produce, as well as animal meats. Many aspects of HEV pathogenesis, replication, and immunological responses remain unknown, as HEV is an extremely understudied but important human pathogen. This article reviews the current understanding of HEV transmission routes with emphasis on food and environmental sources and the prevalence of HEV in animal species with zoonotic potential in humans.

Preliminary study on the detection of hepatitis E virus (HEV) antibodies in pigs and wild boars in Poland

“…Nonetheless, gender has never been associated with the risk of serological positivity. Moreover, HEV was detected in animals from all age groups and seroprevalence did not differ significantly among these groups (23,24).…”

“…Seroconversion of HEV antibodies in domestic swine occurs following the typical waning in the maternal antibody levels around 8-10 weeks of age. First, IgM peaks in conjunction with faecal viral shedding, followed by IgG peaking in conjunction with clearance of the virus from the faeces (24).…”

“…HEV genotypes 3 and 4 circulate in animals and humans and they are autochthonous in several industrialised countries of Europe, North America, and in Japan (10). Domestic pigs and wild boars are the main animal reservoir of these genotypes (15,18,23), but HEV antibodies have been detected in many other animal species: rats, cats, monkeys, dogs, cattle, sheep, goats, mongooses, rabbits, chickens, ferrets, bats, and deer (11,16,22,24).…”

“…Professionals working in close proximity to swine, swine manure, or sewage, pig farm workers, hunters, and veterinary practitioners may become infected with HEV through occupational activities (18,24). HEV genotype 3 infections have been reported in developed countries in individuals who have consumed raw meat or meat products from deer, wild boars, or pigs (10).…”

Hepatitis-E-Virus

“…Es wurden auch HEV-Infektionen berichtet, die auf den Verzehr von Muscheln und Austern zurückzuführen waren; zudem wurde HEV-RNA in Muscheln nachgewiesen [96,97]. Des Weiteren wurden HEV-Infektionen auch bei Personen beobachtet, die sich überwiegend vegetarisch ernähren, was auf einen weiteren Übertragungsweg hindeutet.…”