Virulence Profiles of Diarrheagenic Escherichia coli Isolated from the Western Region of Ghana

Jpn J Infect Dis. 2021 Mar 24;74(2):115-121. doi: 10.7883/yoken.JJID.2020.356. Epub 2020 Aug 31.

Abstract

Diarrheagenic Escherichia coli (DEC), an important agent of infectious diarrhea, is constantly evolving, making its periodic monitoring necessary. However, the DEC genotypes in Ghana remain uncharacterized. We focused on characterizing the molecular serotypes, virulence factors, multilocus sequence types, and the phylogenetic relatedness among different DEC pathotypes recovered from stool samples of pediatric patients with symptoms of diarrhea from the Western region of Ghana. We detected all five common DEC pathotypes, with the majority of the isolates being enterotoxigenic E. coli (ETEC) harboring the heat-labile enterotoxin gene. The DEC strains exhibited diverse serotypic identity with novel and previously reported outbreak strains. Sequence types (ST) ST38, ST316, and ST1722 were most prevalent, and clonal complex 10 (CC10) was the most common CC. A close evolutionary distance was observed among most of the isolates. Coli surface antigen 6 was the most prevalent (44%, n = 11) ETEC-specific colonization factor. Nearly all the isolates harbored lpfA, and the frequencies of other virulence genes such as pap and cnf1 were 7.9% and 18.4%, respectively. This study provides insights into the important and novel genotypes circulating in the Western region of Ghana that should be monitored for public health.

Keywords: diarrhoeagenic Escherichia coli; pathotypes; sequence type; virulence genes.

MeSH terms

  • Child, Preschool
  • DNA, Bacterial
  • Diarrhea / epidemiology
  • Diarrhea / microbiology*
  • Enteropathogenic Escherichia coli / genetics
  • Enterotoxigenic Escherichia coli / genetics
  • Enterotoxins / genetics
  • Escherichia coli / genetics*
  • Escherichia coli / isolation & purification
  • Escherichia coli / pathogenicity*
  • Escherichia coli Infections / epidemiology
  • Escherichia coli Infections / microbiology*
  • Genes, Bacterial
  • Genotype
  • Ghana / epidemiology
  • Humans
  • Infant
  • Multilocus Sequence Typing
  • Phylogeny
  • Virulence
  • Virulence Factors / genetics

Substances

  • DNA, Bacterial
  • Enterotoxins
  • Virulence Factors