Occurrence and antimicrobial resistance of pathogenic vibrios isolated from green mussel, perna viridis L. 1758 in Bacoor Bay, Cavite, Philippines

Abstract

Objective. To determine the occurrence and antimicrobial resistance of pathogenic vibrios from green mussel, Perna viridis in Bacoor Bay, Cavite. Methods. Vibrios were isolated using TCBS agar and confirmed using API Identification kit. The relationship between the density of vibrios and environmental parameters such as months, harvest sites and other physico-chemical parameters of water was determined. The isolated vibrios were subjected to antibiotic resistance testing to determine the resistance patterns. Results. Pathogenic vibrios were isolated in all of the 90 mussel samples. Of the 183 vibrio isolates, 75 strains were V. alginolyticus and 53 strains belonged to V. cholerae wherein 18 (34%) of these were V. cholerae serotype 01. Forty nine (49) strains belonged to V. parahaemolyticus and six were V. vulnificus. Using the regression analysis, salinity, water temperature and pH have significant correlation on the density of vibrios (p=0.0309) with regression model, total vibrios = -16990763 + 145858 Salinity + 186808 Temperature + 1037886 pH. In the antimicrobial resistance assay, ampicillin had the highest drug resistance (37.8%) followed by nalidixic acid (10.4%), tetracycline (10.4%) and co-trimoxazole (9.3%). Conclusion. Pathogenic vibrios were isolated in mussels of Bacoor, Cavite and can be predicted using salinity, temperature and pH of the water. Thirty six percent (36%) of Vibrio isolates were resistant to ampicillin.