Prevalence of potentially pathogenic bacteria in showers at a long-term nursing care facility

Pathogenic bacteria on environmental surfaces in nursing homes may contribute to the‬ growing burden of healthcare-associated infections (HAIs), particularly as the U.S. population‬ ages and more individuals transition into long-term care. In this study, 70 swab samples were‬ collected from five community shower rooms at a nursing home over three sampling trips. Five‬ common shower surfaces were sampled: the floor drain, shower bench, faucet/valves, shower‬ curtain, and grab bars. Samples were processed in the UTC CIDC microbiology lab and‬ inoculated onto four selective and differential media: Hardy CHROM MRSA agar (for‬ methicillin-resistant‬‭ Staphylococcus aureus‬‭ [MRSA]‬‭ and‬‭ S. pseudintermedius‬‭ [SIM]), mannitol‬ salt agar (for‬‭ S. aureus‬‭ [SA] and‬‭ S. epidermidis‬‭ [SE]),‬‭ eosin methylene blue agar (for enteric‬ bacteria [ENT] and‬‭ Bacillus‬‭ spp. [BAC]), and‬‭ Pseudomonas‬‭ isolation agar (for‬‭ Pseudomonas‬ spp. [PS] and‬‭ P . aeruginosa‬‭ [PSA]). MRSA and SA were‬‭ the most prevalent species overall,‬ particularly on the floor drain (92.9%) and shower bench (64.3% and 71.4%, respectively).‬ Enteric bacteria and‬‭ Pseudomonas‬‭ species were also‬‭ found at high densities in floor drains,‬ confirming this surface as a key contamination hotspot. BAC, while less pathogenic, was present‬ on lower-contact surfaces like grab bars and shower curtains. This study highlights the urgent‬ need for targeted infection control and disinfection strategies in high-risk areas, especially as the‬ nursing home population continues to grow and remains vulnerable to environmental sources of‬ infection.