Isolation of community-acquired methicillin-resistant Staphylococcus aureus in healthy carriers in a Mexican community

Int J Infect Dis. 2014 Jan:18:22-6. doi: 10.1016/j.ijid.2013.08.010. Epub 2013 Oct 2.

Abstract

Objectives: Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) clones are spreading rapidly among the population in many regions worldwide. Little information is available on CA-MRSA in Mexico. The aim of this study was to identify CA-MRSA strains in the nose and throat of healthy people in a Mexican community.

Methods: A total of 131 MRSA strains from the nose and throat obtained from healthy people in Mexico City were characterized. The genes mecA, lukS-PV/lukF-PV, and ACME-arcA were detected by PCR. Staphylococcal cassette chromosome mec (SCCmec), pulsed-field gel electrophoresis (PFGE), and spa typing were performed.

Results: Bacteria that had a Panton-Valentine leukocidin (PVL)-positive gene and SCCmec type IV or V were designated as CA-MRSA strains. We found that 21.4% of MRSA strains were CA-MRSA and that the percentage of CA-MRSA strains was similar in the nose and the throat. A great diversity of profiles was found in the strains identified by PFGE pattern and spa typing. Only one strain similar to the USA300 genotype was found; this strain carried the ACME-arcA gene.

Conclusions: CA-MRSA strains were detected in the nose and throat of healthy people. We identified a high level of genetic diversity among CA-MRSA strains in healthy people of Mexico City, which were different from the USA and pandemic clone profiles.

Keywords: CA-MRSA; Healthy carriers; Mexican community; Nose; Throat.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Bacterial Proteins / genetics
  • Bacterial Toxins / genetics
  • Carrier State / microbiology*
  • Child
  • Child, Preschool
  • DNA, Bacterial / isolation & purification
  • Electrophoresis, Gel, Pulsed-Field
  • Exotoxins / genetics
  • Female
  • Humans
  • Infant
  • Leukocidins / genetics
  • Male
  • Methicillin-Resistant Staphylococcus aureus / genetics*
  • Methicillin-Resistant Staphylococcus aureus / isolation & purification*
  • Mexico
  • Middle Aged
  • Nose / microbiology
  • Penicillin-Binding Proteins
  • Pharynx / microbiology
  • Schools
  • Young Adult

Substances

  • Bacterial Proteins
  • Bacterial Toxins
  • DNA, Bacterial
  • Exotoxins
  • Leukocidins
  • Panton-Valentine leukocidin
  • Penicillin-Binding Proteins
  • mecA protein, Staphylococcus aureus