Prevalenceand Antibiotic Susceptibility Pattern of Pseudomonas aeruginosa and Escherichia coli O157:H7 Isolated from two Hospital Environments in Zaria, Nigeria

Aims: The aim of this study is to determine the prevalence and antibacterial susceptibility of Pseudomonas aeruginosa and Escherichia coli and to screen for Escherichia coli O157:H7.

Study Design: Samples for the studies were collected from surfaces in the hospitals. A total number of 310 samples were collected from the two hospitals; 155 samples were collected.

Place and Duration Studies: Department of Microbiology, Ahmadu Bello University, Zaria, Nigeria. The work was carried out between May 2012 and March 2013.

Methodology: The pathogens were isolated using differential Biochemical tests both conventional and kits were carried out for the identification of the P. aeruginosa and E. coli. The isolates of Escherichia coli were screen for E. coli O157:H7 using serology test. The antimicrobial susceptibility pattern was determined using Kirby-Bauer-CLSI modified single disc diffusion technique.

Results: The results from Major Ibrahim B. Abdullahi memorial hospital showed that 16 (69.6%) and 7 (30.4%) were P. aeruginosa, and E. coli respectively. And from St. Luke Anglican hospital 13 (61.9%), P. aeruginosa and 8 (38.1%) E. coli were isolated. There was zero (0) prevalence of Escherichia coli O157:H7 in the two hospitals selected for the study. Pseudomonas aeruginosa was 100% susceptible to ceftazidime and imipenem, E. coli was also 100% susceptible to gentamicin, cefoxitin and ceftazidime. P. aeruginosa and E. coli were more resistant to tetracycline. The multidrug resistant of the isolates from Major Ibrahim B. Abdullahi memorial hospital showed that 12.5% of P. aeruginosa and 14.3% of E. coli were also multidrug resistant. There was no multidrug resistant isolates among E. coli from St. Luke’s Anglican hospital but 30.8% of P. aeruginosa were multidrug resistant isolates.

Conclusion: The result of this study indicates that inanimate surfaces near infected patients and those frequently touched surfaces within the hospital environment were contaminated by Pseudomonas aeruginosa and Escherichia coli. Therefore, there is need for better improved sanitation in the study sites with concerted efforts in screening and monitoring occurrence of Pseudomonas aeruginosa from time to time.