PLASMID PROFILE ANALYSIS AND CURING OF MULTIDRUG RESISTANT BACTERIA ISOLATED FROM HOSPITALS WASTE DUMP SITE IN CALABAR METROPOLIS, NIGERIA

*I. E. Andy and E. A. Okpo

ABSTRACT

This study investigated the plasmid profile analysis and curing of multidrug resistant bacteria isolated from hospitals waste dump site in Calabar metropolis. Samples collection, identification of bacterial isolates, antibiotic susceptibility of the isolates and multiple antibiotic resistance (MAR) index were done using standard techniques. Plasmid DNA extraction were done using zyppy plasmid miniprep kits. Curing of multidrug resistant bacteria isolates was done using acridine orange and cured isolates were re-subjected to antibiotic susceptibility testing. Replicate data were analysed using analysis of variance and student t-test. The bacteria isolated from samples were Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Streptococcus spp, Salmonella spp, Klebsiella pneumoniae, Providencia spp, Enterobacter aerogenes, Proteus spp, Chryseobacterium spp, Bacillus cereus and Serratia marcescens. There was no significant variation in the number of bacterial isolates from the difference sampling points (p>0.05). Bacteria isolates that showed resistance to at least one member from the three classes of antibiotics used were selected as the multidrug resistance isolates and they were Pseudomonas aeruginosa, Providencia sp, Chryseobacterium sp, Providencia rettgeri, Escherichia coli and Staphylococcus aureus. Their MAR index ranged from 0.8-1.0. The selected MDR isolates were all positive for plasmid DNA with sizes greater than 15kbp. It was observed that after curing, the MDR isolates were sensitive to all the antibiotics they were resistance to, which indicates that their resistance were borne on plasmid. The high prevalence of multidrug resistant bacteria and their various resistance pattern observed in the study represents a potential health risk.

Keywords: Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa.