Environmental Parasitology. Interactions between parasites and pollutants in the aquatic environment

Abstract

Summary :In recent years there has been an increasing number of papers showing how parasitism and pollution can interact with each other in aquatic organisms. Among the variety of investigated aspects especially the combined effects of pollution and simultaneous infection on the health of aquatic hosts (molluscs, crustaceans, fish, mammals) is of considerable interest. Effects of pollution on the occurrence and distribution of parasites is another interesting field of "Environmental Parasitology" attracting increasing attention. This mini-review presents some promising examples of interdisciplinary studies paying attention to the fact that under natural conditions no organism will only be affected by either parasites or pollution.

Microhabitat differences surrounding a pond affects the distribution of trematode parasites among a pulmonate snail community

“…This situation can be extremely important for host species with low vagility (e.g., molluscs) via enhancement of the efficiency of parasite transmission by increasing proximity and encounter rate of parasites with their hosts. Changes to the environmental landscape (Alin et al, 1999;Gill et al, 2001;Beale & Monaghan, 2004;Lafferty & Kuris, 2005;Rodriguez-Preito & Fernandez-Juricic, 2005), pollution (MacKenzie et al, 1995;Morley, 2006;Sures, 2008;Morley, 2010;Marcogliese & Pietrock, 2011), and other alterations to the aquatic environment (Lafferty, 1997;Gerard, 2001;Lafferty & Kuris, 2005;Koprivnikar et al, 2007;Gerard et al, 2008) can influence digenetic trematodes due to their complex life cycles. Multiple hosts involved in these life cycles result in a greater potential for at least one of them to be affected by changes in microhabitat.…”

Avian Schistosomes and Outbreaks of Cercarial Dermatitis

“…Although eutrophication contributes to infection risk, cases of cercarial dermatitis or findings of avian schistosomes have also been reported from oligotrophic or mesotrophic systems (8). In addition, other abiotic and biotic factors and human-induced habitat alterations may influence the occurrence of schistosomes and cercarial dermatitis, such as altered hydrology conditions with water-level fluctuation, ice cover, acidification, or dam constructions (268,292,293), anthropogenic pollutants (268,(294)(295)(296)(297), biodiversity change in terms of introducing nonindigenous species that may affect endemic parasites (298), host susceptibility or resistance (9), predation upon trematode free-swimming larval stages by fish and other aquatic animals (295,299,300), or interspecific competition of parasites within the same snail host (301)(302)(303).…”

Abundance and distribution of endoparasitic helminths in Anabas testudineus (Bloch, 1792) from a polluted beel of Bangladesh

“…However, this will be effective only in some cases. Usually pollutants are taken up by the gills or the intestine and accumulate until they reach a steady state concentration and then part of the substances will be excreted by the organism (Sures 2008). Part of the responses against pollutants and parasites are similar, whereas also parasite-specific host reactions occur.…”