Streptococcus agalactiae clones infecting humans were selected and fixed through the extensive use of tetracycline

Nat Commun. 2014 Aug 4;5:4544. doi: 10.1038/ncomms5544.

Abstract

Streptococcus agalactiae (Group B Streptococcus, GBS) is a commensal of the digestive and genitourinary tracts of humans that emerged as the leading cause of bacterial neonatal infections in Europe and North America during the 1960s. Due to the lack of epidemiological and genomic data, the reasons for this emergence are unknown. Here we show by comparative genome analysis and phylogenetic reconstruction of 229 isolates that the rise of human GBS infections corresponds to the selection and worldwide dissemination of only a few clones. The parallel expansion of the clones is preceded by the insertion of integrative and conjugative elements conferring tetracycline resistance (TcR). Thus, we propose that the use of tetracycline from 1948 onwards led in humans to the complete replacement of a diverse GBS population by only few TcR clones particularly well adapted to their host, causing the observed emergence of GBS diseases in neonates.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Base Sequence
  • Clone Cells
  • DNA Transposable Elements
  • Europe / epidemiology
  • Genes, Bacterial*
  • Genome, Bacterial*
  • High-Throughput Nucleotide Sequencing
  • Humans
  • Molecular Sequence Data
  • North America / epidemiology
  • Phylogeny
  • Polymorphism, Single Nucleotide
  • Selection, Genetic
  • Streptococcal Infections / drug therapy
  • Streptococcal Infections / epidemiology*
  • Streptococcal Infections / microbiology
  • Streptococcus agalactiae / classification
  • Streptococcus agalactiae / drug effects
  • Streptococcus agalactiae / genetics*
  • Streptococcus agalactiae / isolation & purification
  • Tetracycline / pharmacology*
  • Tetracycline Resistance / drug effects*
  • Tetracycline Resistance / genetics

Substances

  • Anti-Bacterial Agents
  • DNA Transposable Elements
  • Tetracycline

Associated data

  • GENBANK/HG939456