Longitudinal study of hepatitis E virus infection in Spanish farrow-to-finish swine herds

Vet Microbiol. 2011 Feb 24;148(1):27-34. doi: 10.1016/j.vetmic.2010.08.010. Epub 2010 Aug 22.

Abstract

Hepatitis E is a zoonotic disease and is highly prevalent in European swine livestock. There is a need to compare the infection dynamics of hepatitis E virus (HEV) between herds with the same production system and determine the percentage of animals that could arrive infected at slaughter age. Therefore, a longitudinal study was performed in six Spanish farrow-to-finish affected farms. Twenty piglets per farm were monitored from nursery to slaughter. RT-PCR and serology techniques were applied to analyze longitudinally collected sera and/or faecal samples. Liver and bile samples were also taken at the abattoir. Anti-HEV IgM were firstly detected at 7 weeks of age in 5 farms whereas at 13 weeks of age in 1 farm (farm 2). At slaughter age 50-100% of pigs had seroconverted to anti-HEV IgG in the former 5 farms whereas in the other herd only 5% of pigs were IgG seropositive (farm 2). Six out of 96 livers and 5 out of 80 biles analyzed were HEV positive at the abattoir (total percentage of infected animals: 11.5%). All these positive animals had already seroconverted except 2 pigs of farm 2. Hence, pigs can be seronegative at slaughter age being infected during the latest fattening period. Manipulation of HEV-infected livers or other organs from pigs could be considered a possible route of transmission in Spanish abattoirs. This study represents the first longitudinal survey on swine HEV infection dynamics conducted in different herds.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abattoirs
  • Animals
  • Antibodies, Viral / blood
  • Bile / virology
  • Feces / virology
  • Female
  • Hepatitis E / epidemiology
  • Hepatitis E / immunology
  • Hepatitis E / veterinary*
  • Hepatitis E virus / genetics
  • Hepatitis E virus / immunology
  • Hepatitis E virus / isolation & purification*
  • Immunoglobulin G / blood
  • Immunoglobulin M / blood
  • Liver / virology
  • Livestock / virology
  • Longitudinal Studies
  • Phylogeny
  • RNA, Viral / analysis
  • Reverse Transcriptase Polymerase Chain Reaction / veterinary
  • Sequence Analysis, RNA
  • Spain / epidemiology
  • Swine / virology*
  • Swine Diseases / epidemiology
  • Swine Diseases / immunology
  • Swine Diseases / virology*

Substances

  • Antibodies, Viral
  • Immunoglobulin G
  • Immunoglobulin M
  • RNA, Viral