TY - JOUR
T1 - Repeated cross‑sectional sampling of pigs at slaughter indicates varying age of hepatitis E virus infection within and between pig farms
AU - Meester, Marina
AU - Bouwknegt, Martijn
AU - Hakze-van der Honing, Renate
AU - Vernooij, Hans
AU - Houben, Manon
AU - van Oort, Sophie
AU - van der Poel, Wim H M
AU - Stegeman, Arjan
AU - Tobias, Tijs
N1 - Publisher Copyright:
© 2022. The Author(s).
PY - 2022/7/7
Y1 - 2022/7/7
N2 - Humans can become infected with hepatitis E virus (HEV) by consumption of undercooked pork. To reduce the burden of HEV in humans, mitigation on pig farms is needed. HEV is found on most pig farms globally, yet within-farm seroprevalence estimates vary considerably. Understanding of the underlying variation in infection dynamics within and between farms currently lacks. Therefore, we investigated HEV infection dynamics by sampling 1711 batches of slaughter pigs from 208 Dutch farms over an 8-month period. Four farm types, conventional, organic, and two types with strict focus on biosecurity, were included. Sera were tested individually with an anti-HEV antibody ELISA and pooled per batch with PCR. All farms delivered seropositive pigs to slaughter, yet batches (resembling farm compartments) had varying results. By combining PCR and ELISA results, infection moment and extent per batch could be classified as low transmission, early, intermediate or late. Cluster analysis of batch infection moments per farm resulted in four clusters with distinct infection patterns. Cluster 1 farms delivered almost exclusively PCR negative, ELISA positive batches to slaughter ( PCR−ELISA+), indicating relatively early age of HEV infection. Cluster 2 and 3 farms delivered 0.3 and 0.7 of batches with intermediate infection moment (PCR+ELISA+) respectively and only few batches with early infection. Cluster 4 farms delivered low transmission (PCR−ELISA−) and late infection (PCR+ELISA−) batches, demonstrating that those farms can prevent or delay HEV transmission to farm compartments. Farm type partly coincided with cluster assignment, indicating that biosecurity and management are related to age of HEV infection.
AB - Humans can become infected with hepatitis E virus (HEV) by consumption of undercooked pork. To reduce the burden of HEV in humans, mitigation on pig farms is needed. HEV is found on most pig farms globally, yet within-farm seroprevalence estimates vary considerably. Understanding of the underlying variation in infection dynamics within and between farms currently lacks. Therefore, we investigated HEV infection dynamics by sampling 1711 batches of slaughter pigs from 208 Dutch farms over an 8-month period. Four farm types, conventional, organic, and two types with strict focus on biosecurity, were included. Sera were tested individually with an anti-HEV antibody ELISA and pooled per batch with PCR. All farms delivered seropositive pigs to slaughter, yet batches (resembling farm compartments) had varying results. By combining PCR and ELISA results, infection moment and extent per batch could be classified as low transmission, early, intermediate or late. Cluster analysis of batch infection moments per farm resulted in four clusters with distinct infection patterns. Cluster 1 farms delivered almost exclusively PCR negative, ELISA positive batches to slaughter ( PCR−ELISA+), indicating relatively early age of HEV infection. Cluster 2 and 3 farms delivered 0.3 and 0.7 of batches with intermediate infection moment (PCR+ELISA+) respectively and only few batches with early infection. Cluster 4 farms delivered low transmission (PCR−ELISA−) and late infection (PCR+ELISA−) batches, demonstrating that those farms can prevent or delay HEV transmission to farm compartments. Farm type partly coincided with cluster assignment, indicating that biosecurity and management are related to age of HEV infection.
KW - HEV
KW - virus
KW - zoonosis
KW - population infection dynamics
KW - seroprevalence
KW - within-farm transmission
KW - batch sampling
UR - http://www.scopus.com/inward/record.url?scp=85133561105&partnerID=8YFLogxK
U2 - 10.1186/s13567-022-01068-3
DO - 10.1186/s13567-022-01068-3
M3 - Article
C2 - 35799280
SN - 1746-6148
VL - 53
SP - 1
EP - 12
JO - BMC Veterinary Research
JF - BMC Veterinary Research
IS - 1
M1 - 50
ER -