Tracing Hepatitis E Virus in Pigs From Birth to Slaughter

Area of Science:

• Veterinary Virology
• Foodborne Pathogens
• Swine Health

Background:

• Pigs are a primary reservoir for hepatitis E virus (HEV) genotypes 3 and 4.
• High prevalence of HEV in swine herds poses a risk of human exposure through the food chain.

Purpose of the Study:

• To investigate HEV infection dynamics in pigs from birth to slaughter.
• To assess the impact of maternal antibodies on HEV infection and shedding.
• To determine HEV presence in pigs at the time of slaughter.

Main Methods:

• Longitudinal sampling of serum and feces from 104 pigs (weeks 1-17).
• Real-time RT-PCR for HEV RNA detection.
• Commercial ELISA for HEV-specific antibodies.
• Post-slaughter sampling of feces and organs from 10 pigs.

Main Results:

• 65.5% of pigs tested positive for HEV RNA at least once.
• High levels of maternal antibodies (MAbs) were associated with reduced HEV shedding.
• HEV RNA was detected in feces and organs, but not muscle, of 30% of pigs at slaughter.
• MAbs did not affect the onset or duration of shedding.

Conclusions:

• A significant proportion of pigs in HEV-positive herds become infected and shed the virus during the finisher stage.
• Maternal antibodies play a role in reducing HEV shedding prevalence.
• Sow vaccination is a potential strategy to decrease HEV prevalence in slaughter-age pigs.