284. Efficacy of Skin and Nasal Povidone-Iodine Preparation and Iodine-containing Formulations in Treating MRSA Colonization of Ex Vivo Mucosal Tissue Model
Session: Poster Abstract Session: HAI: MSSA, MRSA, and other Gram-Positives
Thursday, October 27, 2016
Room: Poster Hall
  • ID week poster 284 Peterson et al final.pdf (462.8 kB)
  • Background: Mupirocin decolonization of nasal Staphylococcus aureus prior to surgery decreases surgical site infections (SSIs), however, treatment is 5 days and resistance occurs. 3M™ Company povidone-iodine (PVP-I) based Skin and Nasal Antiseptic (SNP) has rapid, broad spectrum antibacterial activity and resistance is low. Recently, a clinical trial of SNP nasal decolonization resulted in significantly fewer S. aureus SSIs than mupirocin-treated patients; therefore, iodine-containing formulations are being considered as alternatives to mupirocin. The aim of this study was to determine the efficacy of 3M™ SNP and iodine containing-formulations (Betadine® Solution and Clorox Healthcare™ Nasal Antiseptic Swabs) in treating methicillin-resistant S. aureus (MRSA) colonization of ex vivo mucosal tissue.

    Methods: Explants of porcine vaginal mucosa (PVM, 5 mm, full-thickness squamous epithelium) were infected with MRSA USA300 LAC strain (1 x 106CFU/explants). Following 2h infection, explants were treated with Betadine® Solution, 3M™ SNP, or Clorox Healthcare™ Nasal Antiseptic for 1 h or left untreated. Explants were washed with PBS + 2% mucin to mimic mucocilliary clearance and incubated at 37˚C for 1 h, 6 h, or 24 h. Bacteria were enumerated by transferring explants to neutralization broth, vortex mixing and plating. Data presented are M ± SEM, N ≥ 3, n=3.

    Results: Treatment with 3M™ SNP, Betadine® Solution or Clorox Healthcare™ Nasal resulted in a 4.6 ± 1.9 log10, 4.8 ± 1.9 log10 or 3.1 ± 1.9 log10 reduction in MRSA (CFU/explants), respectively. All were significantly different from untreated control 1 h post-wash. 3M™ SNP had significant persistence at 6 h (4.4 ± 1.3 log10 reduction) and at 24 h. By 24 h, regrowth was observed in some treatment groups, however the antimicrobial effect of 3M™ SNP was significantly better than that of all other treatments (6.0 ± 1.7 log10 versus Betadine® Solution’s 1.9 ± 1.8 log10, or Clorox Healthcare™ Nasal’s 2.8 ± 1.8 log10 difference from untreated controls).

    Conclusion: Iodine-containing formulations significantly reduce MRSA colonization of ex vivo mucosal tissue at 1 h; however, 3M™ SNP was persistent and superior to other iodine-containing formulations for reducing MRSA burden over 24h.

    Marnie Peterson, PharmD, PhD1, Michele Anderson, PhD1, Laura Breshears, PhD1, Tera Nordby, BS2, Michelle Hulse Stevens, MD2 and Matt Scholz, MS2, (1)Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, MN, (2)Infection Prevention Division, 3M Company, St. Paul, MN


    M. Peterson, 3M: Grant Investigator and Scientific Advisor , Consulting fee and Research support

    M. Anderson, 3M: Grant Investigator , Research support

    L. Breshears, 3M: Grant Investigator , Research support

    T. Nordby, 3M: Employee and Shareholder , Salary

    M. Hulse Stevens, 3M: Employee and Shareholder , Salary

    M. Scholz, 3M: Employee and Shareholder , Salary

    Findings in the abstracts are embargoed until 12:01 a.m. CDT, Wednesday Oct. 26th with the exception of research findings presented at the IDWeek press conferences.