A total of 60 samples (25 each of fish samples and fish surface swabs and 10 dried salt fish samples) collected from various markets of Hyderabad were subjected to cultural and PCR methods for the presence of Listeria monocytogenes. Primers derived from hlyA and iap genes were used for the detection of Listeriolysin O and p60 respectively. Four samples (2 fish samples, 2 fish surface swabs) were positive by PCR assay, whereas only two samples (one each of fish samples and fish surface swabs) were positive by cultural methods for presence of Listeria monocytogenes. The PCR assay detected hlyA gene of L.monocytogenes in only one fish sample. The presence of this organism in seafood is a great public health concern. The results of this study suggest that PCR could be an excellent tool for detection of Listeria monocytogenes in sea foods as well as in livestock foods.
