First Expert Elicitation of Knowledge on Drivers of Emergence of Bovine Besnoitiosis in Europe

Abstract

Bovine besnoitiosis (BB) is a chronic and debilitating parasitic disease in cattle caused by the protozoan parasite Besnoitia besnoiti. South European countries are affected and have reported clinical cases of BB. However, BB is considered as emerging in other countries/regions of central, eastern and northern Europe. Yet, data on drivers of emergence of BB in Europe are scarce. In this study, fifty possible drivers of emergence of BB in cattle were identified. A scoring system was developed per driver. Then, the scoring was elicited from eleven recognized European experts to: (i) allocate a score to each driver, (ii) weight the score of drivers within each domain and (iii) weight the different domains among themselves. An overall weighted score was calculated per driver, and drivers were ranked in decreasing order of importance. Regression tree analysis was used to group drivers with comparable likelihoods to play a role in the emergence of BB in cattle in Europe. Finally, robustness testing of expert elicitation was performed for the seven drivers having the highest probability to play a key role in the emergence of BB: i.e., (i) legal/illegal movements of live animals from neighbouring/European Union member states or (ii) from third countries, (iii) risk of showing no clinical sign and silent spread during infection and post infection, (iv) as a consequence, difficulty to detect the emergence, (v) existence of vectors and their potential spread, (vi) European geographical proximity of the pathogen/disease to the country, and (vii) animal density of farms. Provided the limited scientific knowledge on the topic, expert elicitation of knowledge, multi-criteria decision analysis, cluster and sensitivity analyses are very important to prioritize future studies, e.g., the need for quantitative import risk assessment and estimation of the burden of BB to evidence and influence policymaking towards changing (or not) its status as a reportable disease, with prevention and control activities targeting, firstly, the top seven drivers. The present methodology could be applied to other emerging animal diseases.

First report of Besnoitia bennetti in Irish donkeys: an emerging parasitic disease in Europe

“…Serological results also suggested the role of African lions (Panthera leo) and wild cats ( Felis sylvestris catus ) in the biological cycle of the parasite [ 48 , 49 ]; however, attempts to confirm domestic cats as the definitive host have been unsuccessful [ 1 ]. Trans-boundary animal trade and movement was identified as a risk factor for the establishment of new outbreaks of bovine besnoitiosis in naive areas [ 2 , 50 ]. Interestingly, one of the clinically affected donkeys reported in the study from the UK [ 23 ] originated from the Irish herd of The Donkey Sanctuary.…”

First Expert Elicitation of Knowledge on Possible Drivers of Observed Increasing Human Cases of Tick-Borne Encephalitis in Europe

“…The methodology followed in this expert elicitation of knowledge is the same as that previously published by the UREAR-ULiège for other emerging/zoonotic diseases [ 39 , 40 , 41 ], but adapted by a panel of experts for TBE. Briefly, we listed 59 possible drivers grouped in eight domains and elicited forty European experts to: (i) allocate a score per driver, (ii) weight this score within each domain, and (iii) weight the different domains and attribute an uncertainty level per domain.…”

“…A driver was defined as a factor that has the potential to directly or indirectly precipitate (“drive”) or lead to the emergence or increasing incidence of TBE in humans. A former questionnaire created to rank drivers of the emergence of animal and zoonotic diseases [ 39 , 40 , 41 ] was adjusted to capture specific possible drivers for TBE. Overall, fifty-nine drivers were identified and classified in eight different domains ( Table A1 ).…”

Validation of a commercial version of a competitive enzyme linked immunosorbent assay for the detection of antibodies to Besnoitia besnoiti

“…Insects are able to transfer the infection by horizontal mechanical transmission, but most likely only over very short distances [ 8 ]. Animal trade and transportation as well as the inadvertently incorporation of infected animals into naïve herds are regarded the main way by which the infection spreads in regions and crosses borders of countries [ 1 , 2 ] as recently also mentioned in an expert elicitation [ 9 ].…”