Background: Single room isolation with contact precautions is widely regarded as a fundamental strategy to prevent the transmission of multidrug-resistant organisms (MDROs). However, its implementation demands substantial resources, limiting its universal application to all MDROs. In this study, we assessed the effect of discontinuing single room isolation for vancomycin-resistant Enterococcus (VRE). Methods: This is a retrospective, observational study conducted at a single 750-bed tertiary center. We conducted an interrupted time series analysis to compare incidence rates and trends of new-onset VRE colonization and bacteremia during the one year before and after the strategy change on January 1, 2023. Results: Single-room occupancy decreased from 79.7% pre-intervention to 23.6% postintervention (P < 0.001). The incidence rate of new-onset VRE colonization was 0.452 and 0.535 per 1,000 patient-days in the pre- and post-intervention periods, respectively, with no statistically significant difference (P = 0.202). However, there was a slightly increasing trend (0.036 [95% confidence interval, −0.002, 0.074] increase per month, P = 0.066). The new-onset VRE bacteremia incidence rate was not differed in incidence (0.060 and 0.055, P= 0.571) or trend (P = 0.720). Conclusion Our study suggests that discontinuing single-room isolation for VRE patients may not affect the incidence of new-onset VRE bacteremia, but caution is needed due to the potential increase in colonization.

Background: Since the emergence of hypervirulent strains of Clostridioides difficile, the incidence of C. difficile infections (CDI) has increased significantly. Methods: To assess the incidence of CDI in Korea, we conducted a prospective multicentre observational study from October 2020 to October 2021. Additionally, we calculated the incidence of CDI from mass data obtained from the Health Insurance Review and Assessment Service (HIRA) from 2008 to 2020. Results: In the prospective study with active surveillance, 30,212 patients had diarrhoea and 907 patients were diagnosed with CDI over 1,288,571 patient-days and 193,264 admissions in 18 participating hospitals during 3 months of study period; the CDI per 10,000 patientdays was 7.04 and the CDI per 1,000 admission was 4.69. The incidence of CDI was higher in general hospitals than in tertiary hospitals: 6.38 per 10,000 patient-days (range: 3.25–12.05) and 4.18 per 1,000 admissions (range: 1.92–8.59) in 11 tertiary hospitals, vs. 9.45 per 10,000 patient-days (range: 5.68–13.90) and 6.73 per 1,000 admissions (range: 3.18–15.85) in seven general hospitals. With regard to HIRA data, the incidence of CDI in all hospitals has been increasing over the 13-year-period: from 0.3 to 1.8 per 10,000 patient-days, 0.3 to 1.6 per 1,000 admissions, and 6.9 to 56.9 per 100,000 population, respectively. Conclusion The incidence of CDI in Korea has been gradually increasing, and its recent value is as high as that in the United State and Europe. CDI is underestimated, particularly in general hospitals in Korea.

Background: Single room isolation with contact precautions is widely regarded as a fundamental strategy to prevent the transmission of multidrug-resistant organisms (MDROs). However, its implementation demands substantial resources, limiting its universal application to all MDROs. In this study, we assessed the effect of discontinuing single room isolation for vancomycin-resistant Enterococcus (VRE). Methods: This is a retrospective, observational study conducted at a single 750-bed tertiary center. We conducted an interrupted time series analysis to compare incidence rates and trends of new-onset VRE colonization and bacteremia during the one year before and after the strategy change on January 1, 2023. Results: Single-room occupancy decreased from 79.7% pre-intervention to 23.6% postintervention (P < 0.001). The incidence rate of new-onset VRE colonization was 0.452 and 0.535 per 1,000 patient-days in the pre- and post-intervention periods, respectively, with no statistically significant difference (P = 0.202). However, there was a slightly increasing trend (0.036 [95% confidence interval, −0.002, 0.074] increase per month, P = 0.066). The new-onset VRE bacteremia incidence rate was not differed in incidence (0.060 and 0.055, P= 0.571) or trend (P = 0.720). Conclusion Our study suggests that discontinuing single-room isolation for VRE patients may not affect the incidence of new-onset VRE bacteremia, but caution is needed due to the potential increase in colonization.

Implant-associated infections pose significant challenges for diagnosis and treatment due to the formation of biofilm on device surfaces. Biofilms are complex microbial communities that adhere to surfaces and are encased in a self-produced extracellular polymeric substance (EPS) matrix. Their presence on implants can lead to persistent infections, implant failure, and increased morbidity and mortality. This review explores the role of biofilms in the pathogenesis of implant-associated infections and examines current strategies for their diagnosis and prevention.

Implant-associated infections pose significant challenges for diagnosis and treatment due to the formation of biofilm on device surfaces. Biofilms are complex microbial communities that adhere to surfaces and are encased in a self-produced extracellular polymeric substance (EPS) matrix. Their presence on implants can lead to persistent infections, implant failure, and increased morbidity and mortality. This review explores the role of biofilms in the pathogenesis of implant-associated infections and examines current strategies for their diagnosis and prevention.

Cytomegalovirus (CMV) is the most important opportunistic viral pathogen in solid organ transplant (SOT) recipients.The Korean guideline for the prevention of CMV infection in SOT recipients was developed jointly by the Korean Society for Infectious Diseases and the Korean Society of Transplantation. CMV serostatus of both donors and recipients should be screened before transplantation to best assess the risk of CMV infection after SOT. Seronegative recipients receiving organs from seropositive donors face the highest risk, followed by seropositive recipients. Either antiviral prophylaxis or preemptive therapy can be used to prevent CMV infection. While both strategies have been demonstrated to prevent CMV infection post-transplant, each has its own advantages and disadvantages. CMV serostatus, transplant organ, other risk factors, and practical issues should be considered for the selection of preventive measures. There is no universal viral load threshold to guide treatment in preemptive therapy. Each institution should define and validate its own threshold.Valganciclovir is the favored agent for both prophylaxis and preemptive therapy. The evaluation of CMV-specific cellmediated immunity and the monitoring of viral load kinetics are gaining interest, but there was insufficient evidence to issue recommendations. Specific considerations on pediatric transplant recipients are included.

Background: Single room isolation with contact precautions is widely regarded as a fundamental strategy to prevent the transmission of multidrug-resistant organisms (MDROs). However, its implementation demands substantial resources, limiting its universal application to all MDROs. In this study, we assessed the effect of discontinuing single room isolation for vancomycin-resistant Enterococcus (VRE). Methods: This is a retrospective, observational study conducted at a single 750-bed tertiary center. We conducted an interrupted time series analysis to compare incidence rates and trends of new-onset VRE colonization and bacteremia during the one year before and after the strategy change on January 1, 2023. Results: Single-room occupancy decreased from 79.7% pre-intervention to 23.6% postintervention (P < 0.001). The incidence rate of new-onset VRE colonization was 0.452 and 0.535 per 1,000 patient-days in the pre- and post-intervention periods, respectively, with no statistically significant difference (P = 0.202). However, there was a slightly increasing trend (0.036 [95% confidence interval, −0.002, 0.074] increase per month, P = 0.066). The new-onset VRE bacteremia incidence rate was not differed in incidence (0.060 and 0.055, P= 0.571) or trend (P = 0.720). Conclusion Our study suggests that discontinuing single-room isolation for VRE patients may not affect the incidence of new-onset VRE bacteremia, but caution is needed due to the potential increase in colonization.

Purpose: To identify ceftolozane/tazobactam (C/T)-resistant Pseudomonas aeruginosa isolates in Korea and to investigate the resistance mechanism. Methods: We performed antibiotic susceptibility testing for 42 carbapenem-resistant, non-carbapenemase-producing P. aeruginosa isolates from Korea. Multilocus sequence typing was performed for all isolates. Whole-genome sequencing was performed for four carbapenem-resistant P. aeruginosa isolates, including two C/T-resistant isolates and two C/T-susceptible isolates. Results: We identified two C/T-resistant P. aeruginosa isolates (P70 and P112) among 42 carbapenem-resistant, non-carbapenemase-producing P. aeruginosa isolates. We found multiple amino acid substitutions in AmpC, AmpR, efflux pump systems, and a porin protein in C/T-resistant P. aeruginosa isolates. These were not reported previously in C/T-resistant P. aeruginosa isolates. Conclusion C/T-resistant P. aeruginosa isolates with multiple amino acid alterations were identified, implying that resistance to this novel antibiotics should be constantly monitored.

Background: Single room isolation with contact precautions is widely regarded as a fundamental strategy to prevent the transmission of multidrug-resistant organisms (MDROs). However, its implementation demands substantial resources, limiting its universal application to all MDROs. In this study, we assessed the effect of discontinuing single room isolation for vancomycin-resistant Enterococcus (VRE). Methods: This is a retrospective, observational study conducted at a single 750-bed tertiary center. We conducted an interrupted time series analysis to compare incidence rates and trends of new-onset VRE colonization and bacteremia during the one year before and after the strategy change on January 1, 2023. Results: Single-room occupancy decreased from 79.7% pre-intervention to 23.6% postintervention (P < 0.001). The incidence rate of new-onset VRE colonization was 0.452 and 0.535 per 1,000 patient-days in the pre- and post-intervention periods, respectively, with no statistically significant difference (P = 0.202). However, there was a slightly increasing trend (0.036 [95% confidence interval, −0.002, 0.074] increase per month, P = 0.066). The new-onset VRE bacteremia incidence rate was not differed in incidence (0.060 and 0.055, P= 0.571) or trend (P = 0.720). Conclusion Our study suggests that discontinuing single-room isolation for VRE patients may not affect the incidence of new-onset VRE bacteremia, but caution is needed due to the potential increase in colonization.

Implant-associated infections pose significant challenges for diagnosis and treatment due to the formation of biofilm on device surfaces. Biofilms are complex microbial communities that adhere to surfaces and are encased in a self-produced extracellular polymeric substance (EPS) matrix. Their presence on implants can lead to persistent infections, implant failure, and increased morbidity and mortality. This review explores the role of biofilms in the pathogenesis of implant-associated infections and examines current strategies for their diagnosis and prevention.