Farm biosecurity measures to prevent hepatitis E virus infection in finishing pigs on endemically infected pig farms

Marina Meester; Tijs J Tobias; Jan van den Broek; Carmijn B Meulenbroek; Martijn Bouwknegt; Wim H M van der Poel; Arjan Stegeman

doi:10.1016/j.onehlt.2023.100570

Farm biosecurity measures to prevent hepatitis E virus infection in finishing pigs on endemically infected pig farms

Marina Meester^*, Tijs J Tobias, Jan van den Broek, Carmijn B Meulenbroek, Martijn Bouwknegt, Wim H M van der Poel, Arjan Stegeman

^*Corresponding author for this work

Research output: Contribution to journal › Article › Academic › peer-review

Abstract

Hepatitis E virus (HEV) can be transmitted from pigs to humans and cause liver inflammation. Pigs are a major reservoir of HEV and most slaughter pigs show evidence of infection by presence of antibodies (ELISA) or viral RNA (PCR). Reducing the number of HEV infected pigs at slaughter would likely reduce human exposure, yet how this can be achieved, is unknown. We aimed to identify and quantify the effect of biosecurity measures to deliver HEV negative batches of pigs to slaughter.

A case-control study was performed with Dutch pig farms selected based on results of multiple slaughter batches. Case farms delivered at least one PCR and ELISA negative batch to slaughter (PCR−ELISA−), indicating absence of HEV infection, and control farms had the highest proportion of PCR and/or ELISA positive batches (PCR+ELISA+), indicating high within-farm transmission. Data about biosecurity and housing were collected via a questionnaire and an audit. Variables were selected by regularization (LASSO regression) and ranked, based the frequency of variable selection. The odds ratios (OR) for the relation between case-control status and the highest ranked variables were determined via grouped logistic regression.

Thirty-five case farms, with 10 to 60% PCR−ELISA− batches, and 38 control farms with on average 40% PCR+ELISA+ batches, were included. Rubber and steel floor material in fattening pens had the highest ranking and increased the odds of a PCR−ELISA− batch by 5.87 (95%CI 3.03–11.6) and 7.13 (95%CI 3.05–16.9) respectively. Cleaning pig driving boards weekly (OR 1.99 (95%CI 1.07–3.80)), and fly control with predatory flies (OR 4.52 (95%CI 1.59–13.5)) were protective, whereas a long fattening period was a risk. This study shows that cleaning and cleanability of floors and fomites and adequate fly control are measures to consider for HEV control in infected farms. Yet, intervention studies are needed to confirm the robustness of these outcomes.

Original language	English
Article number	100570
Pages (from-to)	1-8
Number of pages	8
Journal	One Health
Volume	16
Early online date	27 May 2023
DOIs	https://doi.org/10.1016/j.onehlt.2023.100570
Publication status	Published - Jun 2023

Bibliographical note

Publisher Copyright:
© 2023 The Author(s)

Funding

This work was part of the project “HEVentie: hepatitis E virus intervention in primary pig production”. HEVentie receives financial support of the Topsector AgriFood ( TKI AF 18119 ). Within TKI Agri&Food private partners, research institutes and government cooperate to innovations for safe and healthy food for 9 billion people on a resilient globe. The work was supported by the European Union's Horizon 2020 Research and Innovation Programme under grant agreement No. 773830 : One Health European Joint Programme ( BIOPIGEE: Biosecurity Practices for Pig Farming Across Europe ).

Funders	Funder number
Horizon 2020	773830
Top Sector Agri and Food	TKI AF 18119

Keywords

HEV
Mitigation
Risk factors
Zoonosis
Foodborne
Within-farm transmission

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

Access to Document

10.1016/j.onehlt.2023.100570Licence: CC BY

1-s2.0-S2352771423000903-mainFinal published version, 2.75 MBLicence: CC BY

Cite this

@article{f5f4cc0633574835a55d2e0212634bc0,

title = "Farm biosecurity measures to prevent hepatitis E virus infection in finishing pigs on endemically infected pig farms",

abstract = "Hepatitis E virus (HEV) can be transmitted from pigs to humans and cause liver inflammation. Pigs are a major reservoir of HEV and most slaughter pigs show evidence of infection by presence of antibodies (ELISA) or viral RNA (PCR). Reducing the number of HEV infected pigs at slaughter would likely reduce human exposure, yet how this can be achieved, is unknown. We aimed to identify and quantify the effect of biosecurity measures to deliver HEV negative batches of pigs to slaughter.A case-control study was performed with Dutch pig farms selected based on results of multiple slaughter batches. Case farms delivered at least one PCR and ELISA negative batch to slaughter (PCR−ELISA−), indicating absence of HEV infection, and control farms had the highest proportion of PCR and/or ELISA positive batches (PCR+ELISA+), indicating high within-farm transmission. Data about biosecurity and housing were collected via a questionnaire and an audit. Variables were selected by regularization (LASSO regression) and ranked, based the frequency of variable selection. The odds ratios (OR) for the relation between case-control status and the highest ranked variables were determined via grouped logistic regression.Thirty-five case farms, with 10 to 60% PCR−ELISA− batches, and 38 control farms with on average 40% PCR+ELISA+ batches, were included. Rubber and steel floor material in fattening pens had the highest ranking and increased the odds of a PCR−ELISA− batch by 5.87 (95%CI 3.03–11.6) and 7.13 (95%CI 3.05–16.9) respectively. Cleaning pig driving boards weekly (OR 1.99 (95%CI 1.07–3.80)), and fly control with predatory flies (OR 4.52 (95%CI 1.59–13.5)) were protective, whereas a long fattening period was a risk. This study shows that cleaning and cleanability of floors and fomites and adequate fly control are measures to consider for HEV control in infected farms. Yet, intervention studies are needed to confirm the robustness of these outcomes.",

keywords = "HEV, Mitigation, Risk factors, Zoonosis, Foodborne, Within-farm transmission",

author = "Marina Meester and Tobias, {Tijs J} and {van den Broek}, Jan and Meulenbroek, {Carmijn B} and Martijn Bouwknegt and {van der Poel}, {Wim H M} and Arjan Stegeman",

note = "Publisher Copyright: {\textcopyright} 2023 The Author(s)",

year = "2023",

month = jun,

doi = "10.1016/j.onehlt.2023.100570",

language = "English",

volume = "16",

pages = "1--8",

journal = "One Health",

issn = "2352-7714",

publisher = "Elsevier",

}

TY - JOUR

T1 - Farm biosecurity measures to prevent hepatitis E virus infection in finishing pigs on endemically infected pig farms

AU - Meester, Marina

AU - Tobias, Tijs J

AU - van den Broek, Jan

AU - Meulenbroek, Carmijn B

AU - Bouwknegt, Martijn

AU - van der Poel, Wim H M

AU - Stegeman, Arjan

PY - 2023/6

Y1 - 2023/6

N2 - Hepatitis E virus (HEV) can be transmitted from pigs to humans and cause liver inflammation. Pigs are a major reservoir of HEV and most slaughter pigs show evidence of infection by presence of antibodies (ELISA) or viral RNA (PCR). Reducing the number of HEV infected pigs at slaughter would likely reduce human exposure, yet how this can be achieved, is unknown. We aimed to identify and quantify the effect of biosecurity measures to deliver HEV negative batches of pigs to slaughter.A case-control study was performed with Dutch pig farms selected based on results of multiple slaughter batches. Case farms delivered at least one PCR and ELISA negative batch to slaughter (PCR−ELISA−), indicating absence of HEV infection, and control farms had the highest proportion of PCR and/or ELISA positive batches (PCR+ELISA+), indicating high within-farm transmission. Data about biosecurity and housing were collected via a questionnaire and an audit. Variables were selected by regularization (LASSO regression) and ranked, based the frequency of variable selection. The odds ratios (OR) for the relation between case-control status and the highest ranked variables were determined via grouped logistic regression.Thirty-five case farms, with 10 to 60% PCR−ELISA− batches, and 38 control farms with on average 40% PCR+ELISA+ batches, were included. Rubber and steel floor material in fattening pens had the highest ranking and increased the odds of a PCR−ELISA− batch by 5.87 (95%CI 3.03–11.6) and 7.13 (95%CI 3.05–16.9) respectively. Cleaning pig driving boards weekly (OR 1.99 (95%CI 1.07–3.80)), and fly control with predatory flies (OR 4.52 (95%CI 1.59–13.5)) were protective, whereas a long fattening period was a risk. This study shows that cleaning and cleanability of floors and fomites and adequate fly control are measures to consider for HEV control in infected farms. Yet, intervention studies are needed to confirm the robustness of these outcomes.

AB - Hepatitis E virus (HEV) can be transmitted from pigs to humans and cause liver inflammation. Pigs are a major reservoir of HEV and most slaughter pigs show evidence of infection by presence of antibodies (ELISA) or viral RNA (PCR). Reducing the number of HEV infected pigs at slaughter would likely reduce human exposure, yet how this can be achieved, is unknown. We aimed to identify and quantify the effect of biosecurity measures to deliver HEV negative batches of pigs to slaughter.A case-control study was performed with Dutch pig farms selected based on results of multiple slaughter batches. Case farms delivered at least one PCR and ELISA negative batch to slaughter (PCR−ELISA−), indicating absence of HEV infection, and control farms had the highest proportion of PCR and/or ELISA positive batches (PCR+ELISA+), indicating high within-farm transmission. Data about biosecurity and housing were collected via a questionnaire and an audit. Variables were selected by regularization (LASSO regression) and ranked, based the frequency of variable selection. The odds ratios (OR) for the relation between case-control status and the highest ranked variables were determined via grouped logistic regression.Thirty-five case farms, with 10 to 60% PCR−ELISA− batches, and 38 control farms with on average 40% PCR+ELISA+ batches, were included. Rubber and steel floor material in fattening pens had the highest ranking and increased the odds of a PCR−ELISA− batch by 5.87 (95%CI 3.03–11.6) and 7.13 (95%CI 3.05–16.9) respectively. Cleaning pig driving boards weekly (OR 1.99 (95%CI 1.07–3.80)), and fly control with predatory flies (OR 4.52 (95%CI 1.59–13.5)) were protective, whereas a long fattening period was a risk. This study shows that cleaning and cleanability of floors and fomites and adequate fly control are measures to consider for HEV control in infected farms. Yet, intervention studies are needed to confirm the robustness of these outcomes.

KW - HEV

KW - Mitigation

KW - Risk factors

KW - Zoonosis

KW - Foodborne

KW - Within-farm transmission

UR - http://www.scopus.com/inward/record.url?scp=85160851995&partnerID=8YFLogxK

U2 - 10.1016/j.onehlt.2023.100570

DO - 10.1016/j.onehlt.2023.100570

M3 - Article

C2 - 37363225

SN - 2352-7714

VL - 16

SP - 1

EP - 8

JO - One Health

JF - One Health

M1 - 100570

ER -

Farm biosecurity measures to prevent hepatitis E virus infection in finishing pigs on endemically infected pig farms

Abstract

Bibliographical note

Funding

Keywords

UN SDGs

Access to Document

Other files and links

Fingerprint

Cite this