Molecular detection of Angiostrongylus vasorum in gastropods in Surrey, UK

Surrey, a county in southern England, is a hot spot for angiostrongylosis in domestic dogs but there have been no investigations into the intermediate hosts of Angiostrongylus vasorum in this area. This study aimed to determine the prevalence of A. vasorum in gastropods in Guildford, the most populous town in Surrey, and to ascertain which gastropod species can act as intermediate hosts for A. vasorum. Gastropods (n=97) were sampled in six locations, representing urban, suburban and rural environments and identified to species based on morphological features. A PCR assay was used to detect A. vasorum DNA in gastropod tissue and the species of infected specimens was confirmed by sequencing of mitochondrial genes. 4.1% (4/97) of sampled gastropods and 9.1% (4/44) of sampled slugs were A. vasorum positive. Infected gastropod species were Arion rufus (n=3) and Deroceras invadens (n=1), the first description of the latter species as a potential intermediate host for A. vasorum. Two infected slugs were sampled in urban environments and two in suburban environments. The results demonstrate that there is a risk of transmission of A. vasorum to domestic dogs from the gastropod population in urban and suburban areas of Guildford