Work

Environmental Reservoirs of bla, qnr and mcr-1 Resistance Genes in Enterobacteriaceae from Animal and Wastewater Sources in Daloa, Côte d’Ivoire

Year: 2025

Type: article

Abstract: The environmental spread of antibiotic resistance genes is an increasing public health concern, particularly in resource-limited countries where waste management systems are often inadequate. This study aimed to identify Enterobacteriaceae in different ecosystems of Daloa city (Côte d’Ivoire) and to assess the occurrence of critical resistance genes, including bla-TEM, bla-SHV, bla-CTX-M, qnrA, qnrB, qnrS, and mcr-1. Forty samples were collected from poultry and pig feces, wastewater from gutters, and a water body receiving domestic waste. Bacteria were isolated on selective media, identified using the API 20E system, and subjected to multiplex PCR for resistance gene detection. A total of 60 isolates were recovered, primarily Escherichia coli (73.3%), followed by Salmonella spp. (13.3%), Enterobacter cloacae (8.3%), and Klebsiella oxytoca (5%). The most frequently detected genes were qnrB (30%) and bla-SHV (15%), whereas mcr-1 was not detected in any isolate. Analysis of gene distribution across environments revealed that quinolone resistance genes were generally more widespread and prevalent than β-lactam resistance genes. These findings underscore the role of environmental ecosystems in the dissemination of antibiotic resistance and highlight the urgent need to strengthen surveillance and waste management strategies.

Source: American journal of microbiological research

DOI: 10.12691/ajmr-13-5-3