Occurrence and Antimicrobial Resistance of Pathogenic Vibrios Isolated from Green Mussel, Perna viridis L. 1758 in Bacoor Bay, Cavite, Philippines

Norbel A. Tabo,1,2 Vivian B. Ramirez,2 Hazel Anne L. Tabo2 and Nina G. Gloriani1

1Medical Microbiology Department, College of Public Health,
University of the Philippines-Manila
2Biological Sciences Department, College of Science,
De La Salle University- Dasmariñas, Cavite


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 resitance 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 O1. Forty nine (49) strains belonged to 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.

Key Words: antimicrobial susceptibility pattern, occurrence, pathogenic vibrios