Predators, aquatic vectors, and trophic cascades

In a stimulating and thought-provoking review, Lopez and Duffy [1] recently suggested that predation may mediate host-parasite interactions in aquatic ecosystems through density-mediated and trait-mediated indirect effects. Their arguments are compelling, but two issues raised in this excellent paper deserve comment. The first is that vector-borne transmission is rare in aquatic environments, and the second relates to the lack of examples of predator-driven trophic cascades that affect parasites.