Survival and transmission of community-associated methicillin-resistant Staphylococcus aureus from fomites

Am J Infect Control. 2011 Apr;39(3):219-25. doi: 10.1016/j.ajic.2010.07.005.

Abstract

Background: Transmission of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) from fomites appears to play an important role in CA-MRSA outbreaks. However, the amount and duration of transmissibility of MRSA have not been quantified.

Methods: We assessed the survival and transmission of the CA-MRSA strain USA300-0114 from 9 fomites (razors, plastic toys, ceramic, soap, wood, vinyl, towels, bed sheets, and shoulder pads). Fomites were inoculated then briefly pressed onto sterile pigskin at 5 minutes; days 1, 2, 3, 7, and 10; and then weekly for 10 weeks. The experiment was repeated using 2 methicillin-susceptible S aureus (MSSA) and 3 health care-associated (HA) MRSA strains on select fomites.

Result: Bacteria could be transmitted to skin from all fomites except soap. Transmissibility decreased over time but more rapidly from porous (eg, towels) than nonporous (eg, vinyl) fomites (P = .0002), with some fomites showing transmissibility for more than 8 weeks after contamination. The CA-MRSA strain was transmissible longer than the HA-MRSA strains (P < .0001) and 1 MSSA strain.

Conclusion: CA-MRSA strains are transmissible from many fomites to skin with contaminated nonporous fomites exhibiting transmissibility many weeks after contamination. Transmissibility of HA-MRSA strains demonstrated attenuated transmissibility compared with CA-MRSA strains. Findings may have implications for CA-MRSA infection prevention.

MeSH terms

  • Animals
  • Community-Acquired Infections / microbiology*
  • Community-Acquired Infections / transmission
  • Fomites / microbiology*
  • Humans
  • Methicillin-Resistant Staphylococcus aureus / isolation & purification*
  • Microbial Viability*
  • Skin / microbiology
  • Staphylococcal Infections / microbiology*
  • Staphylococcal Infections / transmission
  • Swine
  • Time Factors