The aquatic environment as a reservoir of Vibrio cholerae O1 in hydrographic basins of the state of Pernambuco, Brazil

ScientificWorldJournal. 2013:2013:746254. doi: 10.1155/2013/746254. Epub 2013 Feb 25.

Abstract

After the worldwide cholera epidemic in 1993, permanent environmental monitoring of hydrographic basins was established in Pernambuco, Brazil, where cholera is endemic. After a quiescent period, 4 rfbN (serogroup O1) positive water samples that were culture negative were detected by multiplex single-tube nested PCR (MSTNPCR); 2 of these were also ctxA (cholera toxin) positive. From May to June 2012, 30 V. cholerae O1 isolates were obtained by culturing samples. These isolates were analyzed for the presence of virulence genes by PCR, intergenic spacer region 16S-23S PCR (ISR-PCR), and pulsed field gel electrophoresis (PFGE). The isolates were positive for the rfbN gene and negative for the assessed pathogenic genes and were classified into 2 groups by ISR and the same profile by PFGE. Close genetic similarity was observed between them (2012) and environmental strains from 2004 to 2005, indicating the permanence of endemic V. cholerae O1 in the region.

MeSH terms

  • Bacterial Proteins / analysis
  • Brazil
  • DNA, Bacterial / analysis*
  • DNA, Intergenic / analysis
  • Disease Reservoirs / microbiology*
  • Electrophoresis, Gel, Pulsed-Field
  • Multiplex Polymerase Chain Reaction / methods
  • RNA, Ribosomal, 16S / analysis
  • RNA, Ribosomal, 23S / analysis
  • Vibrio cholerae O1 / classification
  • Vibrio cholerae O1 / genetics
  • Vibrio cholerae O1 / isolation & purification*
  • Virulence Factors / analysis
  • Water Microbiology*

Substances

  • Bacterial Proteins
  • DNA, Bacterial
  • DNA, Intergenic
  • RNA, Ribosomal, 16S
  • RNA, Ribosomal, 23S
  • RfbN protein, Vibrio cholerae
  • Virulence Factors