Angiostrongylus cantonensis and the giant African snail ­ threat or not?

ABSTRACT

Objective: Angiostrongylus cantonensis or the rat lungworm can cause eosinophilic meningitis in humans. The Giant African snail has been reported to be a suitable intermediate host for this parasite. As the population of Giant African snails has recently exploded, there is an increased risk of transmission of this helminths to humans residing in this country. Therefore the objective of this study is to detect the presence of the rat lungworm in the Giant African Snails in Trinidad by conventional polymerase chain reaction (PCR). Design and Methodology: A total of 178 Giant African snails were collected from ten different locations throughout Trinidad. DNA was extracted from 25 mg of the mantle of each Giant African snail using the DNeasy® PoweSoil® Kit. Conventional PCR was performed using the primers AngioF1 and AngioR1 to amplify a 1,134bp fragment of the 18S rRNA gene of Angiostrongylus spp. The PCR reactions and conditions were are adapted from Qvarnstrom et al in 2007(1). Results: Six of the DNA extracted samples were positive for Angiostrongylus spp. by conventional PCR. Conclusion: Giant African snails in Trinidad are a suitable intermediate host for the rat lungworm and can increase transmission of these helminths to humans. Therefore Angiostrongylus cantonensis infection should be considered to be a differential for eosinophilic meningitis in humans.