Roadmap for nematode control strategies

How do intermediate hosts (‘vectors’), where involved in life cycles, influence epidemiology and approaches to control?

Current knowledge of the population dynamics of intermediate hosts (IH) especially snail IH of trematodes, and how they affect epidemiology, is implicit and not explicit.
How does genetic diversity within snail IH species influence their suitability as hosts and asexual amplification of nematodes?
In the absence of favoured IH, can nematodes switch to alternative IH species and maintain transmission?
Can IH populations be manipulated to decrease transmission and infection risk for livestock?

Ecological studies of snail and other relevant IH species especially in situ, to include abiotic (e.g. topography, soil type, climate) and biotic (e.g. competitors, predators, co-infectors) factors that could influence spatial distribution and transmission potential.
Impacts of farm practices on IH habitat and exposure of livestock.
Studies of IH genetics and susceptibility in controlled conditions.

Laboratory investigations on snail IH are compounded by difficulties in keeping populations in captivity (for Galba spp.).
Better ways of quantifying snail IH and infection status at pasture would facilitate field-based population ecology studies.
Using fencing and/or drainage depends on legislation on environmental integrity and farm subsidies.

Suitable snail habitats are well characterised and various topographical and botanic indicators and predictive models have been developed to help identify them, and integration of IH factors in control are mainly based on avoiding these areas.