Roadmap for the development of control strategies for liver fluke

What are we trying to achieve and why? What is the problem we are trying to solve?

• How can we use environmental and other data to predict F.hepatica risk at various geographical levels?
• Prediction of disease risk in space and time would allow farmers to react appropriately and help develop strategies by policymakers and industry

What are the scientific and technological challenges (knowledge gaps needing to be addressed)?

• Empirical approaches to prediction will always be limited by the scope of the data used to calibrate them, so involve substantial and ongoing work to enable expansion to other areas and to future conditions.
• New data streams from remote sensing greatly enhance availability of environmental information but this must be matched by management and parasitological data to transform hazard prediction into risk prediction.

What approaches could/should be taken to address the research question?

Recent studies have explored the use of very high‐resolution satellite and drone imagery to map small water bodies and the intermediate host snails on pasture, but further research is required to make this approach operational and to develop sustainable business cases. Enhanced capability to monitor water bodies at high spatial resolution could be provided by recent sentinel European Space Agency (ESA) satellites, which carry a range of technologies, such as radar and multi‐spectral imaging instruments for land, ocean and atmospheric observation
(https://sentinel.esa.int).

What else needs to be done before we can solve this need?

• Correlations between remotely sensed data and environmental drivers of transmission (e.g. water bodies versus soil saturation) must be demonstrated.
• Systems for automated processing of streamed data on important environmental, climatic, management and parasitological factors, conversion to useful risk predictions, and delivery to end users in a timely and usable way.

Existing knowledge including successes and failures

Despite the important progress in this area, the spatial distribution of F. hepatica in southern, central and eastern Europe, remains poorly described. Furthermore, additional research is required to improve the spatial resolution of
F. hepatica risk maps from broad administrative or farm level to pasture level so that risk maps can support the implementation of specific management advices on drainage, grazing strategies and targeted (selective) treatments.