Emerging resistant strains: a atudy of the antibiotic resistance of enterococcus species isolated in Pasig River, Manila, Philippines (2012)

Abstract

The Pasig River is one of the major waterways in the country, connecting Laguna de Bay and Manila Bay. It traverses most of Metro Manila and has been used as a commercial route by boats and ferries since the Spanish Era. It now serves as sites for different industrial and residential areas despite the presence of wastes and other microorganisms. The objective of this study is to isolate and detect the antibiotic resistance of Enterococcus species present in Pasig River. Water samples from Pasig River were collected from 10 sites. These were subjected to Direct Plate Counting to determine the present microbial load of Pasig River and different biochemical and agar tests to confirm the presence of Enterococcus in the collected water samples. Results of the plate counting showed that Carlos P. Garcia had the lowest microbial load with only 8.63 x 10² CFU/ mL while Quezon Bridge, A. Luna St., P. Tuazon and Nagpayong Ferry Station produced plates that exceeded the significant count of 300 and thus had an average of =3.00 x 10³ CFU/ mL.Upon confirmation of Enterococcus species, 25 isolates were subjected to the Antimicrobial Susceptibility Testing (AST) via the Kirby-Bauer Disk Diffusion Method. All isolates were identified to be resistant to Penicillin and Ampicillin while showing complete susceptibility to High Level Streptomycin. Nine (9) isolates showed intermediate susceptibility to Vancomycin while fifteen (15) isolates showed complete resistance to the antibiotic.