Authors

C Smith²; ER Morgan¹; R Jones³;  ¹ Queen's University Belfast, UK;  ² Aberystwyth University, UK;  ³ IBERS, Aberystwyth University, UK

Discussion

Galba truncatula is the main host of the liver fluke Fasciola hepatica across Europe, North Africa, and South America. As such, understanding the environmental preferences of this species is vital for creating strategies to control this and other trematode infections such as rumen flukes. This systematic literature review evaluated the current understanding of the snail’s environmental preferences to identify factors that might aid control and areas where further research is needed. Searches were conducted across Web of Science and Google Scholar between March and August 2023, with results screened to find papers which explicitly focused on G. truncatula, with a total of 198 papers evaluated. These studies were assessed for risk of bias using the Mixed Methods Appraisal Tool, and the country of origin, habitat type and habitat pH were noted, along with any other information regarding the snail’s environmental preference noted by the authors. The results indicate that the snail is most commonly found in farmland open drainage systems, on river and stream banks, and in pools and ponds, and is capable of surviving across a wide range of climates. However, the impacts of many environmental factors are unclear due to limited data and inconsistent results and terminology between studies. The pH tolerance of the snail is around 5-9, but within this range there are a roughly equal number of studies which state that G. truncatula prefers acidic, basic, or neutral habitats. Overall, the results show that many aspects of the snail’s environmental preferences require further research to clarify abiotic and biotic impacts on populations. This information will be vital in creating robust risk assessments of fluke infection, predicting how the snail and hence trematode transmission may be impacted by climate change, and the opportunities for environmental control strategies.