Abstract
For endemic infections in cattle that are not regulated at the European Union level, such as bovine viral diarrhea virus (BVDV), European Member States have implemented control or eradication programs (CEP) tailored to their specific situations. Different methods are used to assign infection-free status in CEP; therefore, the confidence of freedom associated with the “free” status generated by different CEP are difficult to compare, creating problems for the safe trade of cattle between territories. Safe trade would be facilitated with an output-based framework that enables a transparent and standardized comparison of confidence of freedom for CEP across herds, regions, or countries. The current paper represents the first step toward development of such a framework by seeking to describe and qualitatively compare elements of CEP that contribute to confidence of freedom. For this work, BVDV was used as a case study. We qualitatively compared heterogeneous BVDV CEP in 6 European countries: Germany, France, Ireland, the Netherlands, Sweden, and Scotland. Information about BVDV CEP that were in place in 2017 and factors influencing the risk of introduction and transmission of BVDV (the context) were collected using an existing tool, with modifications to collect information about aspects of control and context. For the 6 participating countries, we ranked all individual elements of the CEP and their contexts that could influence the probability that cattle from a herd categorized as BVDV-free are truly free from infection. Many differences in the context and design of BVDV CEP were found. As examples, CEP were either mandatory or voluntary, resulting in variation in risks from neighboring herds, and risk factors such as cattle density and the number of imported cattle varied greatly between territories. Differences were also found in both testing protocols and definitions of freedom from disease. The observed heterogeneity in both the context and CEP design will create difficulties when comparing different CEP in terms of confidence of freedom from infection. These results highlight the need for a standardized practical methodology to objectively and quantitatively determine confidence of freedom resulting from different CEP around the world.
| Original language | English |
|---|---|
| Pages (from-to) | 4654-4671 |
| Number of pages | 18 |
| Journal | Journal of Dairy Science |
| Volume | 103 |
| Issue number | 5 |
| DOIs | |
| Publication status | Published - 1 May 2020 |
Funding
This work was carried out with the financial support of the Dutch Ministry of Agriculture, Nature and Food Quality and is part of the STOC free project that was awarded a grant by the European Food Safety Authority (EFSA) and was co-financed by public organizations in the countries participating in the study. The assistance of the Irish Cattle Breeding Federation in providing data relating to the Irish CEP is gratefully acknowledged. Scotland's Rural College (SRUC) gratefully acknowledges Helen Carty (SRUC Vet Services), Jenny Purcell, Ian Murdoch, and Paul Gavin (Scottish Government), the SRUC Beef & Sheep KTE Group, and other colleagues at the Epidemiology Research Unit (ERU) for providing information relating to the Scottish CEP. SRUC also acknowledges the Scottish Government for provision of funding to ERU team members under the Strategic Research Program 2016-2021 Research Deliverables 2.2.6 Animal Disease Epidemiology. Also gratefully acknowledged is GDS Brittany for providing information on the CEP that runs in Brittany. We thank Mia Holmberg (SVA, Uppsala, Sweden) for her support in data collection. The authors have not stated any conflicts of interest.
Keywords
- bovine viral diarrhea virus
- control program
- freedom from infection
- surveillance
