Modelling recent and future climatic suitability for fasciolosis in Europe

Abstract

Abstract. Fasciola hepatica is a parasitic worm responsible for fasciolosis in grazed ruminants in Europe. The free-living stages of this parasite are sensitive to temperature and soil moisture, as are the intermediate snail hosts the parasite depends on for its life-cycle. We used a climate-driven disease model in order to assess the impact of recent and potential future climate changes on the incidence of fasciolosis and to estimate the related uncertainties at the scale of the European landmass. The current climate appears to be highly suitable for fasciolosis throughout the European Union with the exception of some parts of the Mediterranean region. Simulated climatic suitability for fasciolosis significantly increased during the 2000s in central and northwestern Europe, which is consistent with an observed increased in ruminant infections. The simulation showed that recent trends are likely to continue in the future with the estimated pattern of climate change for northern Europe, possibly extending the season suitable for development of the parasite in the environment by up to four months. For southern Europe, the simulated burden of disease may be lower, but the projected climate change will increase the risk during the winter months, since the simulated changes in temperature and moisture support the development of the free-living and intra-molluscan stages between November and March. In the event of predicted climate change, F. hepatica will present a serious risk to the health, welfare and productivity of all ruminant livestock. Improved, bespoke control programmes, both at farm and region levels, will then become imperative if problems, such as resistance of the parasite associated with increased drug use, are to be mitigated.

Outbreak of acute fasciolosis in sheep farms in a Mediterranean area arising as a possible consequence of climate change

“…Levels and seasonal patterns of parasite challenge to livestock are likely to be affected by climate change, through direct effects on life cycle stages and intermediate host outside the definitive host (Morgan and Van Dijk, 2012). Our results represent a small-scale validation of the prediction model developed by Caminade et al (2015) at the European level. In southern Europe, altough the simulated burden of fasciolosis is low, projected climate change will affect winter transmission and support the development of the free-living and the intra-molluscan stages (Caminade et al, 2015).…”

“…Our results represent a small-scale validation of the prediction model developed by Caminade et al (2015) at the European level. In southern Europe, altough the simulated burden of fasciolosis is low, projected climate change will affect winter transmission and support the development of the free-living and the intra-molluscan stages (Caminade et al, 2015). The findings of the present study confirm that liver flukes present an increasing, already serious risk to the health, welfare and productivity of sheep, goat and cattle potentially compromising Europe's food security (Caminade et al, 2015).…”

“…Rapsch et al (2008) mention that the distribution of the free-living stages and the intermediate molluscan host, G. truncatula depend on a range of climatic factors, particularly temperature and rainfall, that also affect the survival of F. hepatica eggs and metacercarie. Therefore, climatic factors are seen as sensitive means for forecasting annual F. hepatica prevalence and the geospatial variability of the liver fluke (Lopez et al, 2012;Caminade et al, 2015;Ducheyne et al, 2015). Prediction of infection risk can be used to increase awareness of the possible economic impact on husbandry and allow the organisation of animal health control programmes (Bennema et al, 2010).…”

Implications of between-isolate variation for climate change impact modelling of Haemonchus contortus populations

“…181 Finally, changes in selection pressures under future climate change scenarios and adaptation and 182 evolution of parasite populations in response to these changes is difficult to incorporate into climate 183 impact simulations and as a result most models make assumptions of no adaptation (Rose et al, 184 2015; Caminade et al, 2015). However, such assumptions may be quickly invalidated.…”

Mapping and modelling helminth infections in ruminants in Europe: experience from GLOWORM

“…Furthermore, the climate-based Ollerenshaw Mt model for F. hepatica was expanded (Caminade et al, 2015) and a Q 0 model for H. contortus developed, tested and validated (Bolajoko et al, 2015), with a view to the apply these model frameworks on a spatial basis in future.…”