The purpose of the study was to record different intermediate hosts of A. cantonensis
and to determine the infection prevalence and intensity of this parasite in freshwater
snails in relation to some ecological and biological factors. The study was conducted
at Al-Salam irrigation Canal and Al-Abtal village (north Sinai) for one year, from
March 2004 to February 2005. Thirteen species of freshwater snails of nine families
were examined for A. cantonensis infection. Six species were found infected with A.
cantonensis larvae. These species were L. carinatus, C. bulimoides, C. cyclostomoides,
B. alexandrina, L. natalensis and M. tuberculta. The infection prevalence of A. cantonensis
in the examined snails ranged from 0.63 to 2.24%. L. carinatus snail had the highest
prevalence, mean abundance and mean intensity of A. cantonensis infection. Positive
correlations were found between both prevalence and mean abundance of A. cantonensis
and host size in L. carinatus and M. tuberculata. Negative correlations were detected
between salinity and prevalence, mean abundance and mean intensity of larvae of A.
cantonensis. The results demonstrated seasonal and spatial variation in the prevalence,
mean abundance and mean intensity of infection among examined snails. In this study,
A. cantonensis larvae were found in a wide range of freshwater snails and M. tuberculata
snail was recorded as a new intermediate host for the first time. In conclusion, further
investigations in other areas and controlled laboratory experiments of infection approaches
are required to evaluate the possible threat of this parasite on humans.