Still not sterile: viability-based assessment of the skin microbiome following pre-surgical application of a broad-spectrum antiseptic reveals transient pathogen enrichment and long-term recovery

• DOI: 10.1128/spectrum.02873-24
• Publication Date: 2025-04-10T13:02:16Z
• Authors: Elizabeth C. Town...; Kayla Xu; Karinda De La Cruz; Lynda Huang; Shelby Sandstrom; Delanie Arend; Owen Gromek; John Scarborough; Anna Huttenlocher; Angela L. F. Gibson; Lindsay R. Kalan
• Keywords: Bioburden; Antiseptic; Propidium monoazide

ABSTRACT Broad-spectrum antiseptics such as chlorhexidine gluconate (CHG) have widespread use pre-surgical tools to lower skin microbial burden and reduce the risk of surgical site infection. However, short- long-term effects CHG on healthy communities remain undefined due confounding binding with persistent bacterial DNA surface. Here, we aim accurately characterize immediate impact preparation CHG-based human microbiome. Twenty-eight patients undergoing elective surgeries were enrolled. Swabs a control microbiome collected at multiple time points before up 2 weeks after surgery. A propidium monoazide (PMAxx)-based viability assay was optimized selectively evaluate from live microbes in complex viability-qPCR viable 16S ribosomal RNA gene profiling. Pre-operative induces measurable reduction bioburden site. On day surgery, sites displayed significant increase relative abundance several SSI-associated genera including Acinetobacter, Bacillus, Escherichia-Shigella, Pseudomonas compared baseline. Bacillus species isolated subjects baseline also demonstrate resistance minimum inhibitory concentrations exceeding 1,000 µg/mL. Although there are major shifts upon exposure CHG, find that these largely transient. For majority individuals, community structure recover near by post-surgical follow-up. IMPORTANCE Surgical infections continue occur despite adoption antiseptics. Before often wash their whole body times (CHG)-based antiseptic soap applied operating room. persisting dead cells skin. We target CHG. Our findings application significantly reduces skin; however, potentially pathogenic bacteria remain. Post-surgery, eventually recovers resemble its pre-CHG exposed state. Collectively, identify tangible avenues for improving formulations further support is viable, stable, resilient chemical perturbation.