Using multi-criteria risk ranking methodology to select case studies for a generic risk assessment framework for exotic disease incursion and spread through Europe.

We present a novel approach of using the multi-criteria pathogen prioritisation methodology as a basis for selecting the most appropriate case studies for a generic risk assessment framework. The approach uses selective criteria to rank exotic animal health pathogens according to the likelihood of introduction and the impact of an outbreak if it occurred in the European Union (EU). Pathogens were evaluated based on their impact on production at the EU level and international trade. A subsequent analysis included criteria of relevance to quantitative risk assessment case study selection, such as the availability of data for parameterisation, the need for further research and the desire for the case studies to cover different routes of transmission. The framework demonstrated is flexible with the ability to adjust both the criteria and their weightings to the user's requirements. A web based tool has been developed using the RStudio shiny apps software, to facilitate this.

Foot and mouth disease risk assessment in Mongolia--local expertise to support national policy.

To address weaknesses in the current foot and mouth disease (FMD) control system and to inform the formulation of a national control strategy, Mongolia conducted two separate risk assessments, one for the Eastern region which in the past has seen re-current introductions of infection, and one for the Western region, where freedom from disease had been demonstrated over several years until FMD was re-introduced in 2013. The risk assessment was conducted in three stages: first local experts developed entry, exposure and consequence pathways during separate workshops in both regions, then data was collected, compiled and analysed, and finally, during a second workshop local experts provided risk estimations for both regions and identified recommendations for risk management. Risk estimates for each pathway were individually recorded, which ensured that views of all experts were equally represented in the risk estimation and which allowed assessing possible impact of different factors related to the background of participating local experts on risk estimates. Entry risk pathways with highest risk estimates were related to livestock movements and in the consequence assessment due to direct contacts. Uncertainty, for which disagreement between participants acted as a proxy, was high in entry pathways and in the assessment of effectiveness of control measures. The risk assessment was conducted with local experts who had no previous risk assessment experience. Through their involvement in the whole process however, they assumed a high level of ownership and despite lively discussions for some risk pathways, a high level of agreement was achieved and credible results were communicated to decision makers. Especially valuable were the derived recommendations. Through the risk assessment the local experts gained a thorough understanding of the FMD risk which resulted in sensible and realistic recommendations, which, if implemented, can lead to a sustainable strengthening of the Mongolian capacities to prevent, control and eradicate FMD. The process was underlined by extensive field data collection, which helped to address important data gaps and therefore to improve quality and reliability of findings. The Mongolian veterinary authority was very committed to the risk assessment and several recommendations have already been integrated in the revision of the national FMD strategy.

Implementing a probabilistic definition of freedom from infection to facilitate trade of livestock: putting theory into praxis for the example of bovine herpes virus-1.

International trade of livestock and livestock products poses a significant potential threat for spread of diseases, and importing countries therefore often require that imported animals and products are free from certain pathogens. However, absolute freedom from infection cannot be documented, since all test protocols are imperfect and can lead to false-negative results. It is possible instead to estimate the "probability of freedom from infection" and its opposite, the probability of infection despite having a negative test result. These probabilities can be estimated based on a pre-defined target prevalence, known surveillance efforts in the target population and known test characteristics of any pre-export test. Here, calculations are demonstrated using the example of bovine herpes virus-1 (BoHV-1). In a population that recently became free of BoHV-1 without using vaccination, the probability of being infected of an animal randomly selected for trade is 800 per 1 million and this probability is reduced to 64 (95% probability interval PI 6-161) per 1 million when this animal is tested negatively prior to export with a gB-ELISA. In a population that recently became free of BoHV-1 using vaccination, the probability of being infected of an animal randomly selected for trade is 200 per 1 million, and this probability can be reduced to 63 (95% PI 42-87) when this animal is tested negatively prior to export with a gE-ELISA. Similar estimations can be made on a herd level when assumptions are made about the herd size and the intensity of the surveillance efforts. Subsequently, the overall probability for an importing country of importing at least 1 infected animal can be assessed by taking into account the trade volume. Definition of the acceptable level of risk, including the probability of false-negative results to occur, is part of risk management. Internationally harmonized target prevalence levels for the declaration of freedom from infection from selected pathogens provide a significant contribution to the facilitation of international trade of livestock and livestock products by allowing exporting countries to design tailor-made output-based surveillance programs, while providing equivalent guarantees regarding the probability of freedom from infection of the population. Combining this with an approach to assess the overall probability of introducing at least 1 infected animal into an importing country during a defined time interval will help importing countries to achieve their desired level of acceptable risk and will help to assess the equivalence of animal health and food safety standards between trading partners.

Assessment of the prevalence of Trichinella spp. in red foxes and Eurasian lynxes from Switzerland.

Trichinella spp. larvae have not been detected in Swiss pigs, horses, or wild boar for many decades, whereas the parasite was repeatedly isolated from red foxes and Eurasian lynxes. Whenever the isolated larvae could be subjected to genotyping, T. britovi was found as infective agent. The present study was initiated to re-assess the epidemiological situation of Trichinella infection in Swiss carnivorous wildlife, namely in red foxes and lynxes. Tissue samples from 1,298 foxes were collected between 2006 and 2007, and those of 55 lynxes between 1999 and 2007. All samples were tested by a standard artificial digestion method and a multiplex-PCR to determine the species and/or genotypes of recovered larvae. Trichinella larvae were found in 21 foxes (1.6%) and 15 lynxes (27.3%), and T. britovi was identified as infecting species in all cases. The geographic distribution of positive foxes showed two main clusters: one in Central Switzerland and one in the West of the country, where also many lynxes were found to be positive. While the prevalence for Trichinella infection in foxes was not statistically correlated with sex or age class, the prevalence in lynx was significantly higher in males compared to females, and in adults compared to juveniles.