Autochthonous Angiostrongylus cantonensis, Angiostrongylus vasorum, Aelurostrongylus abstrusus and Troglostrongylus brevior infections in native terrestrial gastropods from the Canary Islands

Abstract

The presence of zoonotic relevant Angiostrongylus cantonensis infections has recently been reported in rat final hosts and gastropod intermediate hosts in Tenerife, Spain. However, actual data on A. cantonensis-, Angiostrongylus vasorum-, Aelurostrongylus abstrusus and Troglostrongylus brevior prevalences in endemic slug/snail intermediate hosts in other islands of the Macaronesian Archipelago are still missing. In order to fill this gap, we conducted carried out an epidemiological study on terrestrial native slug (Plutonia lamarckii) and snail (Cornu aspersum, Theba pisana) species in 27 selected locations of Tenerife, Gran Canaria, Fuerteventura, Lanzarote, La Palma and El Hierro. Overall, 131 terrestrial slugs and snails were collected during the in winter/spring season 2018/2019 and examined searching for the presence of metastrongyloid lungworm larvae via artificial digestion. The current data revealed a total prevalence of 4.6% for A. vasorum, 3.8% for A. abstrusus, and 0.8% for A. cantonensis in Macaronesian gastropods. In Tenerife, four lungworm species were detected in intermediate hosts, thereby re-confirming A. cantonensis endemicity for this island. Of note, snails (C. aspersum) originating from El Hierro showed rather high prevalences for A. abstrusus (5%) and A. vasorum (15%) in combination with considerable larval burdens (up to 290 larvae per specimen). This epidemiological study expands the geographic distribution of human, canine and feline lungworm species in Spain. The current data -particularly those on anthropozoonotic A. cantonensis -call for a regular large-scale monitoring on intermediate hosts, paratenic hosts and final hosts to pretend further spread of lungworm-related diseases in man and animals.