Molecular Surveillance and Dissemination of Klebsiella pneumoniae on Frequently Encountered Surfaces in South African Public Hospitals

Microb Drug Resist. 2022 Mar;28(3):306-316. doi: 10.1089/mdr.2020.0546. Epub 2021 Jun 24.

Abstract

Bacteria that cause life-threatening illnesses in humans are also capable of contaminating hospital surfaces, thus pose as a potential source of infection. This study aimed to investigate the prevalence, genetic diversity, virulence, and antibiotic resistance profile of Klebsiella pneumoniae in South Africa. In a nonoutbreak setting involving four public hospitals, 777 samples were collected in three different wards from 11 different sites. Phenotypic and genotypic methods were used for isolation and identification. The Kirby-Bauer disk-diffusion method was used to examine antibiotic resistance followed by the combination disk method to characterize extended-spectrum β-lactamases (ESBLs). Antibiotic resistance and virulence genes were screened using PCR and clonality was investigated using enterobacterial repetitive intergenic consensus (ERIC)-PCR. Seventy-five (10%) K. pneumoniae isolates were recovered. These isolates were obtained from all four hospitals and all three wards involved. However, only six frequently touched surfaces were contaminated. Thirty (40%) isolates were characterized as ESBLs showing high resistance to antibiotics and mostly harboring the blaCTX-M group one gene. Virulence genes were highly prevalent among all the isolates. ERIC-PCR showed that the isolates recovered from different sites within the same hospital were genetically similar. The study highlighted that K. pneumoniae can contaminate various surfaces and this persistence allows for the dissemination of bacteria within the hospital environment. The information from this study can assist hospitals to evaluate and improve current infection prevention and control interventions in place.

Keywords: Klebsiella pneumoniae; South Africa; antibiotic resistance; bacterial contamination; clonality; public hospital environment; virulence factors.

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Drug Resistance, Multiple, Bacterial / genetics
  • Genes, Bacterial
  • Hospitals, Public*
  • Klebsiella pneumoniae / drug effects*
  • Klebsiella pneumoniae / isolation & purification*
  • Microbial Sensitivity Tests
  • Phenotype
  • South Africa / epidemiology
  • beta-Lactamases / genetics

Substances

  • Anti-Bacterial Agents
  • beta-Lactamases