1225. How Frequently Should Sink Drains Be Disinfected?

BACKGROUND: New evidence shows the relevance of sink drains in the horizontal transmission of multidrug-resistant organisms. We recently demonstrated that a peroxide-based disinfectant (product B) was better than bleach at disinfecting sink drains; however, we did not determine the duration of this effect. In this study, we evaluate the duration of bacterial reduction in sink drains treated with product B and compared it to an enhanced hydrogen peroxide agent (product A). METHODS: Testing was performed in a 26-bed medical intensive care unit at a 566-bed tertiary care hospital in Milwaukee, WI. Two disinfectants were compared: product A (hydrogen peroxide, octanoic acid, and peroxyacetic acid; Virasept, Ecolab) and product B (hydrogen peroxide-based disinfectant; Peroxide Multi Surface Cleaner and Disinfectant, Ecolab). Sinks were randomly assigned to product A, product B, and control (no disinfection). On day 0, baseline cultures were obtained and disinfectant agents were applied. On post-intervention days 1, 3, 5, and, 7, samples from each drain were collected using E-swabs (Copan, Italy). Quantitation of Gram-negative burden was determined by serial dilution in saline plated to MacConkey agar and dilutions that contained 20–200 colonies were used for bacterial colony-forming units (CFU). Multivariate multiple linear regression and analysis of variance were used to compare mean Ln(1+CFU) between groups using R v3.5.0. Environmental sampling, cultures, and statistical analyses were performed blinded to the disinfected used. RESULTS: All three groups had similar CFU counts at baseline (P > 0.05). On day 1, a statistically significant reduction in bacterial CFUs was observed in the group treated with product A compared with sinks treated with product B (P = 0.04) or the control group (P < 0.01). The same differences were observed on day 3 post-intervention. There were no significant reductions on days 5 and 7. CONCLUSION: Product A was the most effective product at disinfecting sink drains but its effect disappeared at 5 days post-disinfection. These results suggest that treating sink drains every 5 days with a hydrogen peroxide mixture would be ideal for healthcare facilities dealing with sink drain contamination. [Image: see text] DISCLOSURES: All authors: No reported disclosures.