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bioRxiv · 10.1101/2025.08.02.668282

Wild boar trade and African swine fever risk of introduction into new territories: A quantitative release assessment with retrospective data of wild boar shipments to France and Spain (2010-2017).

Abstract

Wild boar (WB) (Sus scrofa) farming and trade in EU countries consistently developed at the end of the last century, primarily for repopulating hunting estates within the sport hunting industry. Since the introduction of African swine fever (ASF) in the Caucasus in 2007 and its subsequent spread from Eastern to Central Europe, international WB trade increased the risk of ASF introduction into new territories. In order to prevent such events, the EU veterinary authorities decided to ban WB trade in June 2018. In our study, we documented retrospective WB trade movements to France and Spain between 2010 and 2017, and used this data to undertake a quantitative risk assessment for ASF introduction resulting from those shipments. A total of 127 trade events introducing live WB into France (n=93) and Spain (n=34) from Eastern EU countries were recorded between 2010 and 2017, encompassing a total of 5567 animals. Hungary was the main exporter to both countries while Poland was the main exporter to France. The highest annual risk of ASF release was related to shipments from Poland to France after 2014 coinciding with an epidemic phase of ASF in that country. During the same period, the risk of ASFV introduction from Hungary to France was much smaller but gradually increased, coinciding with outbreaks in adjacent Ukraine territory during 2015 onward. Despite no outbreaks in France nor Spain were detected to date, quantified values of ASF introduction risk into Western Europe were very high, suggesting that prohibiting international WB trade in 2018 was well justified. Our study highlights the relevance to monitor and supervise more closely legal wildlife production within the EU countries. Our results are an interesting example on how to use trade data to design and implement risk reduction strategies to reduce the spread of pathogens in the wildlife trade sector. Highlights This is the first documented report of the legal trade of live WB between EU countries during the last decade (2010-2017) prior to the EU Commissions decision to prohibit shipments of live wild pigs from ASF-infected areas in June 2018. It provides insight into the level of trade between Eastern and Southern EU countries between 2010 and 2017. Results highlight that the risks of disease introduction and dissemination of African swine fever through the legal wildlife trade during the study period were very high and measures taken by banning WB trade in June 2018 were totally justified. Our data suggest that collecting and sharing information on wildlife production and trade can be beneficial for identifying and managing disease risks. This work served as a good example of a risk assessment exercise with potential applications for other infectious pathogens as well as wildlife production and trade situations such as promoting cross-sector collaboration between animal health, agricultural and wildlife authorities or strengthening the design and implementation of regulations in the surveillance of captive wild animals

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BibTeXRIS

JORI, F., Pleydell, D., BURNICHON, E., Casal, J., Barasona, J. A.. 2025-08-02. Wild boar trade and African swine fever risk of introduction into new territories: A quantitative release assessment with retrospective data of wild boar shipments to France and Spain (2010-2017).. https://doi.org/10.1101/2025.08.02.668282

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