748. The Changing Epidemiology of Clostridioides difficile Infection and the NAP1/027 Strain in Two Quebec Hospitals

Abstract Background In 2003, many hospitals in Québec, Canada experienced an increase in the incidence of healthcare-associated C. difficile infection (HA-CDI) associated with increased morbidity and mortality. This increase was associated with the dissemination of the NAP1/027 strain. The objective of this study was to describe the epidemiology of HA-CDI in two tertiary care hospitals based in Montréal from 2003 to 2019. Methods Surveillance for HA-CDI was performed using standard definitions from 2003 to 2019 at the Montreal General Hospital (MGH) and Royal Victoria Hospital (RVH), in Montréal, Québec. C. difficile was isolated from stool specimens using standard methods. Pulsed field gel electrophoresis and ribotyping were performed to determine genotype. Antibiotic utilization and infection control interventions implemented over the same time period were reviewed. Results A total of 4314 cases of CDAD were identified during the study period: 2295 at the RVH and 2019 at the MGH. The incidence decreased from 29.5 to 5.9 cases per 10,000 patient-days between 2003 and 2019 at the RVH and from 23.8 to 3.9 cases per 10,000 patient-days at the MGH. Of the 124 isolates available for genotyping in 2003, 112 were NAP1 (90.3%) compared to 5 out of 53 (9.4%) in 2019. Fluoroquinolone utilization decreased from 230 to 139 DDDs per 1,000 patient-days between 2003 and 2019, whereas total antibiotic utilization increased from 1296 to 1550 DDDs per 1,000 patient-days. Infection Control interventions included empirically placing patients with diarrhea on precautions, intensified cleaning measures, formal antibiotic stewardship, introduction of a real-time PCR C. difficile test in June 2010, and a move to a facility with only single rooms at the RVH in April 2015. Incidence of HA-CDI at the RVH and MGH and antibiotic utilization between 2003 and 2019 Conclusion An important change in HA-CDI epidemiology was observed in two Canadian tertiary care hospitals based in Montréal between 2003 and 2019. There was a significant decrease in incidence of HA-CDI and a genotype shift from a predominance of NAP1 strains to non-NAP1 strains. Utilization of fluoroquinolones, to which the NAP1 strain is resistant, concurrently decreased. Infection control interventions targeting isolation, diagnosis, disinfection, and antibiotic stewardship have contributed to the major observed reduction in HA-CDI incidence. Disclosures All Authors: No reported disclosures

endonuclease analysis (REA) strain typing was performed on the recovered CD isolates.
Results. Toxin testing was positive in 19/50 (38%) cases. Compared to stool toxin-negative cases, toxin-positive cases were older (95% vs. 71% were age ≥ 65, p = 0.06), more likely to have a history of CDI (37% vs. 23%, p = 0.34), and have ≥ 1 CDI episodes within 6 months (37% vs. 19%, p = 0.26). Treatment for CDI was more common in patients who had a positive toxin text. (95% vs 61%, p= 0.009). Among the 38 patients that received treatment, 33 received vancomycin (87%) and 8 patients (21%) had rCDI at 30 days. Of the 8 patients with rCDI, 2 were re-admitted to the hospital for CDI. The average PCR cycle threshold was lower in the toxin-positive stools compared to toxin-negative stools (24.46 and 29.96, p< 0.001; Fig. 1) The endemic REA group Y was the most common CD strain recovered (30%) and the previously epidemic and virulent REA group BI strain was recovered in 11% of the cases.
Conclusion. CDI cases diagnosed by positive stool PCR and positive toxin tests had more typical risk factors for CDI, a lower PCR cycle threshold and were more likely to have been treated for CDI. Outcomes were similar in this setting where infection with the virulent BI strain was uncommon.
Disclosures Background. Clostridioides difficile is the leading cause of hospital associated infections. In 2017 it lead to an estimated 223,900 cases, 12,800 deaths and $1 billion in attributable healthcare costs. [1] Judicious use of antibiotics and good hand hygiene practices form the cornerstone of prevention. During the COVID-19 pandemic there has been a focus on infection control practices such as hand hygiene, which would also lead to decreased incidence of other contagious infections such as C. difficile diarrhea.
Methods. We looked at the incidence of C. difficile infection in a tertiary care hospital, 1 year before and 1 year after the start of the COVID-19 pandemic. We looked at the absolute number of hospital associated C. difficile infections and the rate per 1000 patient days. The testing methodology changed during the time of the study. Initially it included NAAT for C. difficile, however in March of 2020 the testing strategy included testing for GDH antigen and toxin A/B to differentiate between infection and asymptomatic colonization.
Results. From January 1 st and December 31 st 2019 there were a total of 182 C. difficile infections with a rate of 1.29% per 1000 patient days. Between January 1 st and December 31 st 2020 there were a total of 51 C. difficile infections with a rate of 0.39% per 1000 patient days. There was an absolute risk reduction of 0.9% and relative risk reduction of 69.7%. Hand hygiene audits did not show a difference in adherence between the two periods, with a compliance rate of 98% for both.
Conclusion. Our data suggests that there was a substantial reduction in C. difficile infection rate after widespread knowledge of COVID-19 and implementation of enhanced infection prevention strategies. These included frequent reminders of hand washing, gowning and social distancing to name some. This information was conveyed in the form of widely disseminated signs in highly visible areas, frequent reminders electronically and in person between staff and providers. There are limitations in our study, which include difficulty in longitudinally assessing the extent to which patient care providers adhered to infection prevention strategies and a change in testing strategy for C. difficile diagnosis during this time.
Disclosures. All Authors: No reported disclosures Background. In 2003, many hospitals in Québec, Canada experienced an increase in the incidence of healthcare-associated C. difficile infection (HA-CDI) associated with increased morbidity and mortality. This increase was associated with the dissemination of the NAP1/027 strain. The objective of this study was to describe the epidemiology of HA-CDI in two tertiary care hospitals based in Montréal from 2003 to 2019.

The Changing Epidemiology of Clostridioides difficile Infection and the NAP1/027 Strain in Two Quebec Hospitals
Methods. Surveillance for HA-CDI was performed using standard definitions from 2003 to 2019 at the Montreal General Hospital (MGH) and Royal Victoria Hospital (RVH), in Montréal, Québec. C. difficile was isolated from stool specimens using standard methods. Pulsed field gel electrophoresis and ribotyping were performed to determine genotype. Antibiotic utilization and infection control interventions implemented over the same time period were reviewed.
Results. A total of 4314 cases of CDAD were identified during the study period: 2295 at the RVH and 2019 at the MGH. The incidence decreased from 29.5 to 5.9 cases per 10,000 patient-days between 2003 and 2019 at the RVH and from 23.8 to 3.9 cases per 10,000 patient-days at the MGH. Of the 124 isolates available for genotyping in 2003, 112 were NAP1 (90.3%) compared to 5 out of 53 (9.4%) in 2019. Fluoroquinolone utilization decreased from 230 to 139 DDDs per 1,000 patient-days between 2003 and 2019, whereas total antibiotic utilization increased from 1296 to 1550 DDDs per 1,000 patient-days. Infection Control interventions included empirically placing patients with diarrhea on precautions, intensified cleaning measures, formal antibiotic stewardship, introduction of a real-time PCR C. difficile test in June 2010, and a move to a facility with only single rooms at the RVH in April 2015.
Incidence of HA-CDI at the RVH and MGH and antibiotic utilization between 2003 and 2019 Conclusion. An important change in HA-CDI epidemiology was observed in two Canadian tertiary care hospitals based in Montréal between 2003 and 2019. There was a significant decrease in incidence of HA-CDI and a genotype shift from a predominance of NAP1 strains to non-NAP1 strains. Utilization of fluoroquinolones, to which the NAP1 strain is resistant, concurrently decreased. Infection control interventions targeting isolation, diagnosis, disinfection, and antibiotic stewardship have contributed to the major observed reduction in HA-CDI incidence.
Disclosures. All Authors: No reported disclosures