Q-223. Seasonal Variation of Multiple Antibiotic Resistant Enterococcus Species in Waters and Sediments of Barceloneta-Manatí, Puerto Rico

N. J. Rodríguez, B. R. Zaidi;
Univ. of Puerto Rico, Mayaguez, PUERTO RICO.

Increased use of antibiotics has resulted in a rise on the levels of antibiotic resistant among bacteria that can easily transfer antibiotic resistant to other bacteria. For this reason pattern of antibiotic resistant in Enterococcus spp. was studied. Samples of waters and sediments were collected from Barceloneta- Manati, Puerto Rico. The sampling areas are located near big pharmaceuticals complex as well as dairy industries. Enterococcus spp. was isolated from river, estuarine and coastal water and sediments during the dry and wet periods and used as an indicator of fecal contamination as well as antibiotic resistance. Total numbers of Enterococcus spp. were determined by using selective medium and identified by standard microbial and biochemical techniques. Minimum inhibitory concentration of penicillin, tetracycline and vancomycin was determined by disc diffusion method. Utilization of multiple antibiotics resistance was determined by using microplates. The number of Enterococcus spp. in river, estuarine and coastal area in 2007 was compared with the samples collected during 2006. There was significant decrease in number of Enterococcus spp. in river samples this year compared to last year. However, the number of Enterococcus spp. increased in coastal water. There was also decrease in number of different Enterococcus species in all samples this year. Enterococcus faecalis was the only species common to all sampling sites during 2007. In 2007 there is also an increase in the number of Enterococcus spp. resistant to the combination of penicillin and tetracycline antibiotics in all sampling sites. For example only 42% were resistant to penicillin and tetracycline in 2006 compared to 90 % in 2007. In April 2007 increase in number of Enterococcus spp. resistant to three antibiotic, tetracycline, penicillin and vancomycin at high concentration was observed. This may be due to unusually high concentrations of antibiotics usage reported during this period due to outbreak of disease in dairy industry.