The Application of Loop-Mediated Isothermal Amplification Technique for Epidemic Detection of Angiostrongylus cantonensis in Land Snails

Abstract

Angiostrongylus cantonensis is the most common cause of eosinophilic meningitis. This nematode is found in the pulmonary arteries of rats. The definitive hosts in nature are rodents, while intermediate hosts are several animals including snails. The aim of this study was to detect the epidemiology of A. cantonensis in land snails collected from Ban-Thun and Ban Mae Ka districts. A total of 336 land snails (H. distincta: 112 samples; A. fulica: 112 samples; and C. siamensis: 112 samples) were randomly selected and screened for the presence of A. cantonensis by microscopic examination and loop-mediated isothermal amplification (LAMP). The results of microscopic examination showed 61/336 positive samples (18.15%) in which 24 (7.14%) and 37 (11.01%) samples were A. fulica and C. siamensis, respectively. None of H. distincta was positive for A. cantonensis. However, the LAMP technique showed higher sensitivity in detection of A. cantonensis. Using LAMP, 87/336 samples (25.89%) were positive for A. cantonensis, in which 40 (11.90%), 42 (12.50%), and 5 (1.49%) samples were A. fulica, C. siamensis, and H. distincta, respectively. So far, the LAMP technique allowed higher sensitivity in A. cantonensis detection, indicating its potential to be used as a tool for epidemiological investigation of this organism in various intermediate hosts which might contribute to the transmission of angiostrongyliasis to humans.