Incidence of community acquired ESBL-producing bacteria among asymptomatic University students in Anambra State, Nigeria

  • Chidimma R. Chukwunwejim Department of Pharmaceutical Microbiology and Biotechnology, Enugu State University of Science and Technology, Enugu, Nigeria
  • Peter M. Eze Department of Pharmaceutical Microbiology and Biotechnology, Nnamdi Azikiwe University, Awka
  • Nonye T. Ujam Department of Pharmaceutical Microbiology and Biotechnology, Enugu State University of Science and Technology, Enugu, Nigeria
  • Isaiah C. Abonyi Department of Environmental Health Science, Nnamdi Azikiwe University, Awka, Nigeria
  • Chika P. Ejikeugwu Department of Applied Microbiology, Ebonyi State University, Abakiliki, Nigeria
  • Dominic O. Abony Department of Pharmaceutical Microbiology and Biotechnology, Nnamdi Azikiwe University, Awka, Nigeria
  • Charles O. Esimone Department of Pharmaceutical Microbiology and Biotechnology, Nnamdi Azikiwe University, Awka, Nigeria
Keywords: Extended Spectrum β-Lactamase (ESBL), Antibiotic resistance, Gram-negative bacteria, Asymptomatic, Nigeria


This study was conducted to investigate the incidence of community acquired extended-spectrum β-lactamase (ESBL)-producing bacteria among asymptomatic students of Nnamdi Azikiwe University, Awka, Anambra State, South-East Nigeria. A total of 102 non-duplicate strains of Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa were isolated from fecal samples (n=273) collected from the participating students. The isolates were subjected to antimicrobial susceptibility tests to determine their antimicrobial resistance profile. Their multiple antibiotic resistance (MAR) indices were also evaluated.  Screening of the isolates for possible ESBL production was carried out by disk diffusion test using cefotaxime and ceftazidime disks. ESBL-production by the resistant strains was confirmed using the double-disk synergy test. Most of the isolates were found to be multi-drug resistant, as all K. pneumoniae and P. aeruginosa strains (100%), and 98.4% of the E. coli strains, had MAR indices ≥0.2. A total of 22 ESBL-producing bacterial species were confirmed, and the frequency of E. coli, K. pneumoniae and P. aeruginosa isolates among the ESBL-producing bacteria were n=20 (90.9%), n=2 (9.1%), and n=0 (0.0%) respectively. The total number of ESBL-producing bacterial strains isolated accounted for 8.1 % of the entire sample population. Although this prevalence rate may not indicate an alarming situation, it is important that the proliferation of ESBL-producing bacteria in the community be contained, since a high incidence of ESBL-producing organisms will create significant therapeutic problems in the near future. There is therefore need to develop strategies to reduce their spread in the community especially through monitoring, surveillance and proper detection protocol.



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How to Cite
Chukwunwejim, C., Eze, P., Ujam, N., Abonyi, I., Ejikeugwu, C., Abony, D., & Esimone, C. (2018). Incidence of community acquired ESBL-producing bacteria among asymptomatic University students in Anambra State, Nigeria. European Journal of Biological Research, 8(3), 138-147. Retrieved from
Research Articles