P-253. Impact of Restroom Disinfecting/Cleaning Frequency and Product Selection on Risk of Infection

Abstract Background Restrooms are associated with transmission of bacterial and viral illnesses. Disinfecting pathogen-contaminated surfaces represents an intervention for reducing transmission risk. This study assessed whether cleaning/disinfecting frequency affects bacterial pathogen contamination in American patient rooms, long term care facilities and households with ≥ four occupants. Methods During the control phase, toilet surfaces (toilet bowl, water, and rim) were cleaned using a 9.5% w/w hydrochloric acid product only. During the intervention phase, multiple restroom surfaces (vanity/sink, toilet surfaces, floor, doorknob including toilet bowl) were cleaned/disinfected with disinfecting/cleaning products selected for the specific surfaces. Surface samples were collected and tested for heterotrophic and coliform bacteria after 1, 2, 3, or 7 days, with sampling being randomized during the week. The ratio of E. coli to norovirus in feces from an infected person was then used to perform a quantitative microbial risk assessment. Results The greatest numbers of bacteria were recovered on surfaces after three days. The largest reduction in bacterial recovery occurred during a three-day (∼twice-a-week) cleaning cycle, resulting in statistically significant reductions in recovery of heterotrophic bacteria (P = 0.00898) and Escherichia coli (P = 0.01). Conclusion Quantitative microbial risk assessments of commonly touched surfaces suggests that risk of infection by norovirus (highly contagious, excreted in high numbers, low human infectious dose) may be reduced by 91.5% using a three-day (twice-a-week) restroom cleaning/disinfection cycle. Disclosures Charles P. Gerba, PhD, Rickitt Benckiser: Grant/Research Support