A total of 27 E. coli were isolated from pork samples purchased from various public markets in Laguna. Methods were adapted from the NARMS
(2006) protocol and isolates were identified using traditional biochemical methods and confirmed using RapID™ ONE kit (Remel, ThermoFisher,
USA). Minimum inhibitory concentrations (MICs) against against 9 critically important antimicrobials were determined using the Clinical and
Laboratory Standards Institute (CLSI, 2017) broth microdilution procedure using ATCC 25922 as control. Out of the 19 public markets, 17
were positive for presence of E. coli in pork chops. Among the 27 recovered E. coli isolates, two (7.4%) were suspected as E. coli O157:H7.
Resistance were most frequently observed in tetracycline (96%) and doxycycline (93%), followed by cephalothin (89%), trimethoprim (89%),
ampicillin (78%), chloramphenicol (70%) and ciprofloxacin (48%); whereas fewer resistant isolates were detected against kanamycin (4%) and
gentamicin (4%), with MICs ranging from 4-64 μg/ml. All isolates were resistant to at least three antimicrobials indicating a 100% multidrug
resistant bacterial population. These results suggest pork is an important reservoir of antimicrobial resistant E. coli exposing the public
to potential health hazard which may facilitate dissemination of resistant genes to commensal and enteric bacteria through the food chain.
Gladys Maria Pangga and Jonna Rose Maniwang