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?

To minimise the level of infection and production losses through improved management, integrating all of the various control methods.

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

• There is a lack of evidence on how environmental / pasture / grazing and other tools can be integrated and used to decrease reliance on chemical control and alleviate development of AR.
• Empirically-derived understanding might be limited under different conditions, e.g. as climate and management change.
• Possible external sources of fluke eggs, e.g. from deer, lagomorphs and nutria, might need to be taken into account.

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

Field studies that use and attempt to optimise integrated control, and quantify the benefits, are needed.
Modelling studies can help to generalise the conclusions and apply them to systems where field data are limited, as well as to narrow hypotheses and design efficient studies.

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

• Knowing prevalence of infection and AR, hence the need to change approach.
• Better understanding of environmental drivers of infection is needed to effectively apply integrated control.
• Studies rely on methods to detect infection and these could be improved, e.g. quantification of metacercariae on pasture; detection of eDNA for fluke and snails.
• Solutions limited by the practicality of fencing off or draining waterlogged areas.

Existing knowledge including successes and failures

• Empirical knowledge of the topographical and other environmental determinants of liver fluke risk within farms is sound but avoidance strategies are still not widely applied.
• Predictive understanding is limited to correlates of high infection risk (topography, climate).