Bacteriological Profile and Antibiotic Resistance Patterns of Wastewater Effluents in 2 Hospitals of Ethiopia

Abstract

The wastewater effluent is a hotspot for a multitude of microorganisms, including environmental pathogens, true human pathogens, and animal pathogens. In the absence of standardized wastewater treatment facilities, these pathogens contaminate surface and groundwater, further contributing to the spread of drug-resistant bacteria. This study aimed to investigate the bacteriological profiles and antibiotic resistance patterns in hospital wastewater in Addis Ababa, Ethiopia. A cross-sectional study was conducted from September 2023 to March 2024. Wastewater samples were collected from 2 hospitals using a grab sampling technique. Bacteria were identified using standard biochemical tests and MALDI-TOF Mass Spectrometry. Antibiotic susceptibility testing was performed using the Kirby-Bauer disk diffusion method. Data were verified for completeness and analyzed using the Statistical Package for the Social Sciences version 27. From the total samples collected, 219 bacterial isolates were recovered. The dominant bacteria were K. pneumoniae (57/219; 26%) and E. coli (47/219; 21.5%). K. pneumoniae showed the highest resistance levels to cefuroxime and tetracyclines, each (32/57; 85.1%). The magnitude of ESBLs and carbapenemase producers were (37/195; 19%), and (6/195; 3.1%), respectively. Overall, (115/219; 52.5%) of the isolates were multidrug-resistant. Wastewater generated from hospitals contaminate downstream rivers and pose public health risk. Therefore, proper wastewater treatment is needed.