Antibiogram of Bacteria and Fungi Isolated from Medical and Non-medical Dumpsites in Rivers State

Abstract

Waste dumpsites could serve as reservoir for the transmission of antimicrobial resistant pathogenic microorganisms. The antibiogram of bacteria and fungi isolated from medical and non-medical dumpsites was investigated. Soil samples from the dumpsite of University of Port Harcourt teachings hospital, Rivers State University teachings hospital, NDDC hostel and faculty of Law were collected aseptically into sterile containers and analysed using standard microbiological techniques. The total heterotrophic bacterial counts ranged from 1.1±0.4 to 1.9±0.9×107 CFU/g, the total coliform counts ranged from 4.1±0.3 to 6.8±0.2×104 CFU/g, the staphylococci count ranged from 3.9±0.8×103 to 1.9±0.1×104 CFU/g while the fungal count ranged from 6.5±0.21×104 to 1.25±0.71×105 CFU/g. The percentage occurrence of the bacterial isolates was E. coli (16.7%), Pseudomonas sp (8.3%), Staphylococcus sp (20.8%), Streptococcus sp (4.2%), Bacillus sp (20.8%), Enterobacter sp (12.5%), Klebsiella sp (8.3%), Flavobacterium sp (4.2%) and Micrococcus sp (4.2%). While the percentage occurrence of the fungal isolates was A. niger (14.3%), A. terreus (10.7%), Mucor sp (14.3%), Geotrichum sp (10.7%), Trichoderma sp (7.1%), A. nidulans (3.6%), A. flavus (7.1%), Rhizopus sp (10.7%), Blastomyces sp (10.7%) and Candida albicans (10.7%). The antibiotic susceptibility pattern of Gram-negative bacterial isolates showed that E. coli was 100% resistant to Ampiclox and Augmentin, and 75% resistant to Cefuroxime, Cefotaxime, Imipenem, Gentamycin, Nalidixic acid, Cefuroxime and Cefixime. Klebsiella was 100% resistant to all the antibiotics except levofloxacin, cefuroxime and Imipenem. Enterobacter sp showed 66.7% resistance to cefotaxime, imipenem and cefixime. Pseudomonas sp was 100% resistant to all the antibiotics except gentamycin. Staphylococcus sp was 100% susceptible to erythromycin, tetracycline and ciprofloxacin. Streptococcus sp was 100% susceptible to co-trimazole and vancomycin but completely resistant to Ampicillin, Meropenem, Erythromycin, Tetracycline, Ceftriaxone and Chloramphenicol. The multi-antibiotic-resistant index ranged from 0.2 to 1.0. The dumpsites contained drug-resistant microorganisms that could be a public health significance.