The hepatitis E virus is ubiquitous in all parts of the world where pig
production exists. The infection occurs in several animal species and its
course is mostly asymptomatic. Viral strains isolated from pigs and humans
are genetically similar, which indicates a potential zoonotic nature of the
disease, and the possibility that pigs, and perhaps also other species of
animals diseased with viral hepatitis E are a source of infection to humans.
The pig hepatitis E virus, which is similar to the hepatitis E virus in
humans, was isolated and described for the first time in the USA in 1997. The
infection of pigs with hepatitis E virus occurs through faeco-oral
transmission, by ingestion of feed and water contaminated with the virus, or
through direct contact between infected and healthy animals. The pathogenesis
of this infection in pigs differs from its pathogenesis in humans and it has
not been sufficiently examined in all its aspects. Even though viral
hepatitis E in pigs has been described as a subclinical disease, some authors
describe changes in the concentration of certain biochemical parameters in
blood serum of the infected pigs. Histologically, a mild to moderate
lymphotic-plasma cellular infiltration is observed in livers of infected
pigs, as well as focal areas of hepatocyte necrosis. Viral hepatitis E is an
endemic disease of humans in Asia, Africa, and Latin America. In developed
countries, hepatitis E sporadically occurs in humans, but it is becoming of
increasing importance in particular in Japan, North America, and Europe,
because the populations of these areas travel extensively to the endemic
regions or as a result of the consumption of thermally untreated meat of wild
boar and products made from thermally untreated meat. Pork products can be
contaminated with hepatitis E virus. Further proof that indicates the
zoonotic potential of this virus and places this diseases among the group of
professional diseases of farmers and veterinarians is the finding of
antibodies to hepatitis E virus in farmers and veterinarians who work on pig
farms without showing any clinical signs of the disease. Having in mind the
fact that viral hepatitis E has been proven in pig farms in Serbia and
neighboruign countries, there should be strict respect of biosecutiry
measures from the episootiological and epidemiological aspects, and the
principle of good production and hygiene practice should be adhered to on pig
farms. This disease should in future also be included in the legal
regulations of our country in order to ensure the production of products of
animal origin that are safe from the aspect of hygiene.
Editorial Commentary:The Mystery of Hepatitis E Seroprevalence in Developed Countries: Is There Subclinical Infection due to Hepatitis E Virus?
