420. ­­Impact of Intensified Prevention Measures On Rates of Hospital-Acquired Carbapenem-Resistant Acinetobacter baumannii In Endemic Setting

Abstract Background During the last decade, hospital-acquired carbapenem-resistant Acinetobacter baumannii (HA-CRAB) have become endemic in acute care facilities in Israel. Despite the increasing rates CRAB carriage among hospitalized patients in endemic settings, the role of active surveillance cultures (ASC) is still debated. The aim of the study was to evaluate the impact of different components of control measures conducted in an endemic acute care hospital Methods The study consisted of a 12-month baseline period (1 January 2019–31 December 2019; period 1), 12-month 1st intervention period (1 January 2020- December 2020; period 2); 6-month 2nd intervention period (1 January 2021-30 June 2021; period 3) and a 9-month follow-up period (1 June 2021–31 March 2022; period 4). During period 1, basic infection-control measures were implemented including contact precautions for CRAB carriers. During period 2, all CRAB carries were cohorted in a single ward and managed by dedicated health care workers. Enhanced environmental cleaning was conducted by a dedicated team. During periods 3 and 4, high-risk patients were screened on admission; weekly cultures were obtained in high-risk units. The incidence density rate (IDR) of HA-CRAB was defined as the per-patient number of first CRAB isolate from clinical specimens. Incidence rates ratios (IRR) were compared between the study periods. Results During the baseline period, IDR of HA-CRAB was 4.9/10,000 patient days (PD). During period 2, no significant decrease was observed (IDR 3.9/10,000 PD, IRR 0.7 95% CI 0.49-1.16, p=0.15). In response to ongoing transmission in several wards, ASC program was initiated in January 2021. IDR during period 3 was 5.3/10,000 PD (IRR 1.1, 95% CI 0.74- 1.56, p=0.64). Since January 2021, 2.1% (78/3799) were found to be colonized on admission and 5.5% (100/1809) were detected by weekly screening. Among the 291 patients who were detected with CRAB during this period, 70.9% were identified by ASC. During period 4, IDR was 3.1/10,000 PD (IRR 0.60, 95% CI 0.40-0.88, p=0.007). Conclusion The comprehensive intervention that combined intensified control measures with routine ASC was effective in reducing the incidence of HA-CRAB in endemic setting. Disclosures Yasmin Maor, MD, MSD: Advisor/Consultant|MSD: Honoraria|Pfizer: Honoraria.