High-Touch, High-Risk: An Exploratory Microbiome Analysis of Hospital Wheelchairs.

In this exploratory pilot study, quantitative analyses were performed on seven leather wheelchairs and the protective barrier was evaluated on three leather wheelchairs, while shotgun metagenomic sequencing (Illumina and Oxford Nanopore) was conducted on pooled samples obtained from seven leather and three fabric wheelchairs to characterize microbial DNA recovered from wheelchair surfaces under routine clinical conditions. Microbial DNA and biomass were detected on all sampled surfaces, with median DNA concentrations of approximately 0.015 ng/µL, median cell counts of approximately 4.8 × 105 cells/mL, and median OD600 values of approximately 0.038, although variability among wheelchairs was observed. NGS analysis revealed heterogeneous microbial communities composed mainly of taxa associated with human skin microbiota and environmental sources. Opportunistic taxa including Escherichia coli, Staphylococcus haemolyticus, Achromobacter xylosoxidans, and Clostridioides difficile DNA were detected. Differences in microbial composition were observed between the pooled fabric and leather samples, with fabric samples characterized by the dominance of specific taxa and leather samples exhibiting a more heterogeneous microbial profile. In addition, median DNA concentration, cell counts, and OD600 values were reduced by approximately 98-100% on the protective barrier compared with uncovered wheelchair surfaces, with statistically significant differences between conditions. Overall, these findings suggest that hospital wheelchairs may harbor measurable levels of microbial biomass and microbial DNA despite routine sanitation procedures. Lower contamination levels were observed on the protective barrier under the conditions tested. Due to the exploratory nature of the study, the small sample size, and the use of pooled samples for metagenomic analyses, these observations should be interpreted with caution and require confirmation in larger studies.