Antimicrobial resistance determinants of Escherichia coli isolates recovered from some rivers in Osun State, South-Western Nigeria: Implications for public health

Yinka Titilawo; Larry Obi; Anthony Okoh

doi:10.1016/j.scitotenv.2015.03.095

Antimicrobial resistance determinants of Escherichia coli isolates recovered from some rivers in Osun State, South-Western Nigeria: Implications for public health

Sci Total Environ. 2015 Aug 1:523:82-94. doi: 10.1016/j.scitotenv.2015.03.095. Epub 2015 Apr 7.

Authors

Yinka Titilawo¹, Larry Obi², Anthony Okoh²

Affiliations

¹ SA-MRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice 5700, South Africa; Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, Alice 5700, South Africa. Electronic address: olayinkatemi@yahoo.co.uk.
² SA-MRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice 5700, South Africa; Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, Alice 5700, South Africa.

PMID: 25862994
DOI: 10.1016/j.scitotenv.2015.03.095

Abstract

The inevitable development of resistance has sunk the great success achieved in the discovery of antimicrobial agents and dashed the hope of man in the recovery from infections and illnesses, as diseases and disease agents that were once thought to be controlled by antimicrobials are now re-emerging in new leagues resistance to therapy. A total of 300 PCR confirmed Escherichia coli isolates recovered from different river sources in Osun State, Nigeria were evaluated for their antibiogram profiling by the disc diffusion method and the resistant isolates were further profiled for their genotypic antimicrobial resistance determinants by polymerase chain reaction assays. Among the 20 antimicrobials selected from 10 families, resistance among sulfonamides, β-lactams and tetracyclines were found to be most frequent than phenicols and aminoglycosides with a noticeable increase in the number of multi-drug resistance ranging from three to nine antimicrobials. A total of 19 resistance determinants were assessed with their prevalence and distributions obtained as follows; [sulfonamides sulI (8%), sulII (41%)], [β-lactams; ampC 22%; blaTEM, (21%), and blaZ (18%),], [tetracyclines tetA (24%), tetB (23%), tetC (18%), tetD (78%), tetK (15%), and tetM, (10%)], [phenicols; catI (37%), catII (28%), and cmIA1 (19%)] and [aminoglycosides; aacC2 (8%), aphA1 (80%), aphA2 (80%), aadA (79%) and strA (38%)]. The Pearson chi-square exact test revealed many strong significant associations among ampC, blaTEM, blaZ and tetA genes with some determinants screened. The findings signify high increase in the prevalence of multidrug resistant E. coli isolates and resistance determinants indicating increased public health risks associated with the ingestion of waters from untreated sources. Hence, a necessity for safe water supply, provision of proper sanitation facilities and good surveillance programmes to monitor antimicrobial resistance patterns in water bodies.

Keywords: Escherichia coli; Genetic marker; Multi-drug resistance; Nigeria; Prevalence; Rivers.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Drug Resistance, Multiple, Bacterial / genetics*
Environmental Monitoring
Escherichia coli / classification
Escherichia coli / genetics*
Nigeria
Rivers / microbiology*
Water Microbiology*