Antibiotics | National Survey on Extended-Spectrum Beta-Lactamase (ESBL)-Producing Escherichia coli in Broilers in Indonesia

This study conducted the first nationwide survey on ESBL-producing E. coli in Indonesian broilers, revealing its molecular characteristics and multidrug resistance. The findings provide critical baseline data for monitoring antimicrobial resistance.

 

Literature Overview
This article 'Occurrence and Molecular Characterization of Extended-Spectrum Beta-Lactamase (ESBL)-Producing Escherichia coli in Broilers in Indonesia', published in the journal Antibiotics, reviews and summarizes the national prevalence and molecular features of ESBL-producing E. coli in Indonesian broiler populations. Through large-scale sample analysis, the study provides detailed regional genotype distribution and resistance pattern data.


Background Knowledge
ESBL-producing E. coli is a pathogen resistant to multiple β-lactam antibiotics, primarily mediated by blaCTX-M, blaTEM, and blaSHV genes. These resistant strains pose significant public health risks in clinical and livestock environments. Indonesia's broiler industry is extensive but lacks a national antimicrobial resistance monitoring system. Previous studies indicate widespread blaCTX-M distribution in Asian regions, particularly CTX-M-1 subtypes, while blaTEM and blaSHV are more common in Europe. This study fills the gap in nationwide surveillance, providing scientific evidence for policy formulation and antimicrobial management strategies.

 

 

Research Methods and Experiments
The research team isolated and analyzed 2182 E. coli strains from broiler cecal samples collected across three major regions (East, Central, West) in Indonesia between 2018 and 2020. Antimicrobial susceptibility testing and ESBL phenotypic confirmation were performed following CLSI standards. ESBL-associated genes (blaCTX-M, blaCTX-M-1, blaCTX-M-9, blaTEM, blaSHV, and blaOXA-1) were detected using multiplex/tetraplex PCR. Phylogenetic group analysis was conducted to assess genetic diversity. The experimental workflow included sample collection, bacterial isolation, phenotypic and genotypic identification, resistance analysis, and statistical comparison.


Key Conclusions and Perspectives

• The national average prevalence of ESBL-producing E. coli was 9.9%, with Western Indonesia showing significantly higher rates than Central and Eastern regions (15.2% vs 8.0% and 7.2%).
• 98.5% of ESBL-producing E. coli exhibited multidrug resistance (MDR), including 31% resistant to six antibiotic classes and 3% resistant to nine antibiotic classes.
• blaCTX-M genes were detected in 97.5% of ESBL-producing strains, with blaCTX-M-1 accounting for 97.5% and blaCTX-M-9 only 2.5%.
• blaTEM genes occurred in 33% of ESBL-producing strains, while blaSHV and blaOXA-1 genes were not detected.
• Phylogenetic analysis identified group A (42%) and group E (22.5%) as predominant lineages, with group E showing significantly higher proportions in Eastern Indonesia compared to Western regions.
• Most ESBL-producing strains exhibited high resistance to β-lactam antibiotics (e.g., cefotaxime, ampicillin) but remained susceptible to meropenem and tigecycline.

Research Significance and Prospects
The study highlights the prevalence and multidrug resistance of ESBL-producing E. coli in Indonesia's broiler industry, emphasizing the urgent need for improved antimicrobial management to curb resistant gene dissemination. Future research should integrate whole-genome sequencing and farm-level data to elucidate resistance drivers. Long-term monitoring is essential to evaluate the effectiveness of antimicrobial management policies.

 

 

Conclusion
This study provides the first systematic assessment of ESBL-producing E. coli in Indonesian broilers, including prevalence rates, resistance profiles, genotype distributions, and phylogenetic features. Results demonstrate blaCTX-M dominance, widespread multidrug resistance, and significant regional differences. These findings establish foundational data for antimicrobial policy development by governmental and research institutions. Future efforts should prioritize longitudinal monitoring and whole-genome sequencing to track resistance evolution and implement effective interventions.

 

Nur Hidayatullah, Imron Suandy, Montira Intanon, Riska Desitania, and Nattakarn Awaiwanont. Occurrence and Molecular Characterization of Extended-Spectrum Beta-Lactamase (ESBL)-Producing Escherichia coli in Broilers in Indonesia. Antibiotics.