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?

• What are the important factors governing the amplification of fluke populations and how does this assist propagation of infection?
• Can onward propagation be reduced to below the threshold for population persistence and what is the most efficient way to achieve this?

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

• Level of asexual reproduction within snail hosts appears to vary widely but the role of different factors (e.g. snail genotype and age, competition within snails, microclimatic conditions, parasite strain) has not been elucidated.
• Estimation of R0 for fluke supposes construction and calibration of a mechanistic transmission model, which does not yet exist.

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

• Well-targeted experiments to calibrate R0 estimation.
• Exploration of whether an R0-type model can replicate or improve on the performance of empirical risk models.

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

Similar areas of uncertainty to mathematical models (see 4).

Existing knowledge including successes and failures

• This would be a new approach to fluke epidemiology and could complement other methods.
• Mechanistic, stochastic and R0 models are under development and preliminary models have been published.