Pathogenic Bacteria in Wastewater from Medical City, Baghdad

Abstract

Bacterial contaminants have a direct impact on overall human health. This study focuses on microbial pathogens in sewage discharged from four main municipal stations of BMC/ Baghdad Medical City into the Tigris River. Sensitivity tests were conducted on six isolates against common antibiotics used by Iraqi patients as initial screening tests. The study aimed to characterize prevalent pathogenic and environmental isolates from the Tigris River, receiving sewage water from Baghdad Medical City. Over four months in 2023, two Gram-positive and four Gram-negative bacterial groups were identified in wastewater isolates. Findings highlighted biochemical reactions and antibiotic resistance mechanisms using VITEK 2 Compact Mechanism in the recovered isolates. Two dominant microbial strains in BMC wastewater Klebsiella pneumoniae and Staphylococcus aureus accounted for 34% of a total 106 isolates each. Both strains showed resistance to commonly tested antibiotics with percentages 76% and 62% respectively. Staphylococcus hominis and Pseudomonas putida were a least dominant bacterial groups in sewage samples, accounting for 6.6% each from a total of 106 isolates. However, they showed resistance with percentages 61% and 17% respectively. Each of Ralstonia pickettii and Rhizobium radiobacter accounted for 7.5% and 9.4% from a total of 106 isolates each and were sensitive to most tested antibiotics, with percentage 92% and 90% to respectively. Significant differences (P <0.0001) between the total number of isolates conducted at BMC compared to the control were achieved. Alongside, significant differences between each isolated bacterial group at BMC and UTR were recorded, with results as follows: Staphylococcus hominis, Staphylococcus aureus, Klebsiella Pneumoniae, Rhizobium radiobacter, Ralstonia pickettii, and Pseudomonas putida with (P < 0.000008, 0.000001, 0.000019, 0.000003, 0.00004 and 0.00046), respectively.