Marine snails play an important role in the transmission of cercariae to fish as a source of zoonotic diseases. The current study aimed to screen the collected snails for prevalence of cercarial infections for the whole year using parasitological and molecular genetic methods for 550 marine snails belonging to the genus Nerita. PCR technique using internal transcribed spacer region of ribosomal DNA (ITS-rDNA) specific primers was done to detect the prevalence of larval trematode infection in some infected snails as positive control and all non-infected snails. The results of PCR technique showed higher infection prevalence (55.82%) than classical methods (21.45%). Such studies can assist in collecting data on the ecological relevance of disease distribution in the sympatric fish and the pattern of transmission of digenean trematodes by snails and finally in prevention and control of the following fish and human diseases.