Klebsiella pneumoniae from fuchka: insights into the genetic diversity, virulence, and antibiogram profile.

Abstract

Klebsiella pneumoniae is an emerging pathogen of global concern due to its capacity to acquire antimicrobial resistance and virulence determinants, yet its presence in the food environment remains unexplored. This study investigated the prevalence, antimicrobial resistance, virulence genes, biofilm formation, and genomic characteristics of K. pneumoniae isolated from a widely consumed street food in Bangladesh. A total of 90 fuchka and related samples from different sources were collected and analyzed using culture-based methods, PCR confirmation, matrix-assisted laser desorption ionization time-of-flight assay, and 16S rRNA sequencing. Antibiotic sensitivity was determined using the disk diffusion method, and resistance- and virulence-associated genes were detected by PCR. Biofilm formation was quantified using a 96-well microtiter plate assay, and genetic diversity was assessed by enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) fingerprinting. Whole-genome sequencing (WGS) was performed on four representative isolates for in-depth genomic characterization. K. pneumoniae was recovered from 46.7% of samples. Among the isolates, 37.5% exhibited a multidrug-resistant (MDR) phenotype, with universal resistance to ampicillin. Virulence genes including wabG (90.5%) and uge (95.2%) were highly prevalent, whereas rmpA and bfp were absent. Capsular serotypes K3 and K5 were detected in 16.7% of isolates. The class 1 integron (int1) (83.3%) and tetA (56.7%) were the most frequently detected resistance determinants. Biofilm formation was observed in 31% of isolates and significantly associated with the MDR phenotype. WGS revealed clinically relevant sequence types (ST2262) phylogenomically related to human clinical strains. These findings indicate that fuchka may act as a reservoir for virulent and MDR K. pneumoniae, highlighting the urgent need for improved hygiene practices and integration of street food into the One Health antimicrobial surveillance framework.

Importance: The presence of multidrug-resistant (MDR) Klebsiella pneumoniae in ready-to-eat street foods poses a significant public health concern, particularly in low- and middle-income countries where informal food vending is widespread. Fuchka is consumed daily by diverse population groups in Bangladesh, including children and young adults, making it a potential route for silent transmission of clinically important pathogens. The detection of MDR strains harboring virulence factors, integrons, and biofilm-forming ability suggests an elevated risk of persistence, spread, and limited treatment options in case of infection. This study highlights street food as an overlooked reservoir in the One Health framework, bridging community environments and clinical settings. Improved surveillance, vendor hygiene training, and enforcement of food safety regulations are crucial to reduce the risk of dissemination of these high-risk strains.