Evidence of Invasive Reptiles as Novel Paratenic Hosts of Angiostrongylus cantonensis in the Canary Islands: Implications for Parasite Transmission in Island Ecosystems.

Angiostrongylus cantonensis is an emerging zoonotic nematode whose transmission relies on complex host interactions. Although reptiles are recognized as paratenic hosts, data on invasive reptilian species remain scarce. This study investigated A. cantonensis occurrence in 167 invasive reptiles from the Canary Islands- 51 California kingsnakes (Lampropeltis californiae), 74 Cuban green anoles (Anolis porcatus), and 42 veiled chameleons (Chamaeleo calyptratus)- using nested PCR targeting the internal transcribed spacer 1 (ITS1) region, followed by Sanger sequencing. Parasite DNA was detected in 94.1% of California kingsnakes and 21.6% of Cuban green anoles, whereas all chameleons tested negative. Infection prevalence was significantly higher in California kingsnakes. Neither body size nor sex was associated with infection. These findings provide the first evidence that California kingsnakes and Cuban green anoles act as natural paratenic hosts for A. cantonensis in Europe. The high prevalence in the invasive California kingsnake suggests a key role in amplifying parasite transmission within insular ecosystems, emphasizing the need to incorporate invasive reptiles into One Health surveillance programs to mitigate zoonotic risks and protect biodiversity.