Multiple Antibiotic Resistance Quotients (RQs) of Plesiomonas shigelloides Recovered from some Rivers in Southwest Nigeria

Abstract

The freshwater environment represents a habitat of diverse microorganisms and have also been identified as a contributor to the continuous spread of waterborne diseases in addition to antibiotic resistance determinants.  This study, evaluated antibiotic resistance quotients of Plesiomonas shigelloides isolates recovered from selected freshwaters in Osun and Oyo states, Southwest Nigeria. Water samples, collected over 12 months, were analysed using standard procedures and subsequently confirmed by means of polymerase chain reaction (PCR) technique using PS gene. Confirmed Plesiomonas shigelloides (44%) were screened for in-vitro antibiotic resistance profile against a panel of 20 commonly used antibiotics. Resistance by all P. shigelloides from the selected sampling sites were frequently observed against sulphamethoxazole (100%), erythromycin (87-93%) ampicilin (79-90%), cephalotin (63-82%), streptomycin (55- 64%), and chloramphenicol (48 -58%) though susceptibility against netilmicin (100%), meropenem (91-94%), gentamicin (83-88%), imipenem (72-79%) amikacin (65-70%), ciprofloxacin (68-70%) norfloxacin (54-59%) were similarly observed across all sampled sites. Multiple antibiotic resistance indexes among P. shigelloides across the sampled rivers ranged between 0.14 – 0.62 with highest MAR index of 0.62 recorded in some isolates from SR2 (Dandaru river) and SR4 (Eleyele river). These findings indicated high prevalence of antibiotic resistance P. shigelloides in the freshwater, which may well be attributed to undue antimicrobial usage around the selected rivers, thereby necessitating recommendation of good hygiene and proper sanitation as well as enforcing legislation against indiscriminate use and disposal of antimicrobials in the study communities.