# Multidrug-resistant Klebsiella pneumoniae and Klebsiella oxytoca isolated from backyard broiler chickens and their contacts with antimicrobial resistance genes of Klebsiella pneumoniae

## TL;DR

This study found high rates of multidrug-resistant Klebsiella in backyard chickens and their human contacts, highlighting a public health concern.

## Contribution

The study identifies specific antimicrobial resistance genes in Klebsiella isolates from chickens and humans in a backyard setting.

## Key findings

- Klebsiella pneumoniae and K. oxytoca showed high resistance to erythromycin and clindamycin in both chickens and humans.
- The most common serotype of K. pneumoniae was K1, and resistance genes like ermB, blaTEM, and blaCTX-M1 were frequently detected.
- Multidrug-resistant Klebsiella isolates were found in 11.3% of chicken and 15% of human stool samples.

## Abstract

The objective of this study was to investigate the prevalence and phenotypic identification of antimicrobial resistance of K. pneumoniae and K. oxytoca recovered from backyard broiler chickens and their human contacts. The serotypes and genotypes of antibiotic resistance genes of K. pneumoniae isolates were investigated. A total of 80 samples were collected from backyard broiler chickens that showed signs of illness, sneezing, coughing, and diarrhea. Twenty stool samples were collected from individuals who had been in contact simultaneously. In total, 19 Klebsiella species were isolated, 12 of which were from broiler chicken samples and seven from human stool samples. Recovery rates of K. pneumoniae were 11.3% (n = 9/80) and 15% (n = 3/20) of broiler and human stool samples, respectively. K. oxytoca was detected in 3 of 80 (3.75%) broiler chicken and 4 of 20 (20%) human stool samples. Antimicrobial susceptibility showed that all 19 Klebsiella isolates were resistant to erythromycin and clindamycin (100%), followed by penicillin (94.7%) and ampicillin (84.3%). Within the 12 K. pneumoniae isolates, the most common serotype was K1. Antibiotic resistance gene profile of K. pneumoniae isolates was observed, with a high carrying rate of the macrolide gene ermB (91.7%), followed by the β-lactam genes blaTEM (75%) and blaCTX-M1 (66.7%). In conclusion, the emergence of multidrug-resistant (MDR) bacteria, K. pneumoniae and K. oxytoca in broiler backyard chickens and their human contacts is alarming, particularly for erythromycin and clindamycin. This underscores the need for alternatives like vaccination, probiotics, and better biosecurity to combat antimicrobial resistance.