We aimed to describe the incidence, pathogens, and antimicrobial susceptibility of central line-associated bloodstream infections (CLABSI) in adult intensive care units (ICU).

State surveillance data from 2011 to 2022 were analyzed to identify patient and device days and CLABSI events. Pathogen data were analyzed to determine the most common organisms and patterns of antimicrobial resistance grouped into 3-year time epochs.

Adult ICU in Victoria, Australia.

Healthcare organizations participating in CLABSI state surveillance.

608 events were reported over 751,350 device days. Overall, CLABSI incidence was 0.81 per 1,000 central-line days, with a 49.3% rate reduction from 2011 to 2022 (1.39 to 0.70 per 1,000 central-line days). Overall device utilization ratio was 0.57, with a 15.4% reduction from 2011 to 2022 (0.67 vs 0.56). Of 690 pathogens, the most common by rank order were coagulase-negative Staphylococci (CNS), Candida species, Staphylococcus aureus, and Enterococcus faecalis. The proportion of CNS-causing events increased by 69.0% from 2011 to 2022; this trend was not observed for other organisms. For every increase in epoch, a 33% decrease in methicillin-resistant S. aureus (MRSA), 4% increase in vancomycin-resistant Enterococcus faecium, and 12% increase in ceftriaxone-resistant Escherichia coli pathogens were observed.

We demonstrate a decreasing incidence of CLABSI in Victorian adult ICU and an increasing burden of infections due to CNS. No significant time trend increases in antimicrobial-resistant organisms, including MRSA, vancomycin-resistant E. faecium, and ceftriaxone-resistant E. coli were observed. These findings are relevant for identifying priorities for CLABSI prevention in Victorian adult ICU.

We explored the utility of the standardized infection ratio (SIR) for surgical site infection (SSI) reporting in an Australian jurisdiction.

Retrospective chart review.

Statewide SSI surveillance data from 2013 to 2019.

Individuals who had cardiac bypass surgery (CABG), colorectal surgery (COLO), cesarean section (CSEC), hip prosthesis (HPRO), or knee prosthesis (KPRO) procedures.

The SIR was calculated by dividing the number of observed infections by the number of predicted infections as determined using the National Healthcare Safety Network procedure-specific risk models. In line with a minimum precision criterion, an SIR was not calculated if the number of predicted infections was <1.

A SIR >0 (≥1 observed SSI, predicted number of SSI ≥1, no missing covariates) could be calculated for a median of 89.3% of reporting quarters for CABG, 75.0% for COLO, 69.0% for CSEC, 0% for HPRO, and 7.1% for KPRO. In total, 80.6% of the reporting quarters, when the SIR was not calculated, were due to no observed infections or predicted infections <1, and 19.4% were due to missing covariates alone. Within hospitals, the median percentage of quarters during which zero infections were observed was 8.9% for CABG, 20.0% for COLO, 25.4% for CSEC, 67.3% for HPRO, and 71.4% for KPRO.

Calculating an SIR for SSIs is challenging for hospitals in our regional network, primarily because of low event numbers and many facilities with predicted infections <1. Our SSI reporting will continue to use risk-indexed rates, in tandem with SIR values when predicted number of SSI ≥1.

To compare antimicrobial prescribing practices in Australian hematology and oncology patients to noncancer acute inpatients and to identify targets for stewardship interventions.

Retrospective comparative analysis of a national prospectively collected database.

Using data from the 2014–2018 annual Australian point-prevalence surveys of antimicrobial prescribing in hospitalized patients (ie, Hospital National Antimicrobial Prescribing Survey called Hospital NAPS), the most frequently used antimicrobials, their appropriateness, and guideline concordance were compared among hematology/bone marrow transplant (hemBMT), oncology, and noncancer inpatients in the setting of treatment of neutropenic fever and antibacterial and antifungal prophylaxis.

In 454 facilities, 94,226 antibiotic prescriptions for 62,607 adult inpatients (2,230 hemBMT, 1,824 oncology, and 58,553 noncancer) were analyzed. Appropriateness was high for neutropenic fever management across groups (83.4%–90.4%); however, hemBMT patients had high rates of carbapenem use (111 of 746 prescriptions, 14.9%), and 20.2% of these prescriptions were deemed inappropriate. Logistic regression demonstrated that hemBMT patients were more likely to receive appropriate antifungal prophylaxis compared to oncology and noncancer patients (adjusted OR, 5.3; P < .001 for hemBMT compared to noncancer patients). Oncology had a low rate of antifungal prophylaxis guideline compliance (67.2%), and incorrect dosage and frequency were key factors. Compared to oncology patients, hemBMT patients were more likely to receive appropriate nonsurgical antibacterial prophylaxis (aOR, 8.4; 95% CI, 5.3–13.3; P < .001). HemBMT patients were also more likely to receive appropriate nonsurgical antibacterial prophylaxis compared to noncancer patients (OR, 3.1; 95% CI, 1.9–5.0; P < .001). However, in the Australian context, the hemBMT group had higher than expected use of fluoroquinolone prophylaxis (66 of 831 prescriptions, 8%).

This study demonstrates why separate analysis of hemBMT and oncology populations is necessary to identify specific opportunities for quality improvement in each patient group.

To conduct a pilot study implementing combined genomic and epidemiologic surveillance for hospital-acquired multidrug-resistant organisms (MDROs) to predict transmission between patients and to estimate the local burden of MDRO transmission.

Pilot prospective multicenter surveillance study.

The study was conducted in 8 university hospitals (2,800 beds total) in Melbourne, Australia (population 4.8 million), including 4 acute-care, 1 specialist cancer care, and 3 subacute-care hospitals.

All clinical and screening isolates from hospital inpatients (April 24 to June 18, 2017) were collected for 6 MDROs: vanA VRE, MRSA, ESBL Escherichia coli (ESBL-Ec) and Klebsiella pneumoniae (ESBL-Kp), and carbapenem-resistant Pseudomonas aeruginosa (CRPa) and Acinetobacter baumannii (CRAb). Isolates were analyzed and reported as routine by hospital laboratories, underwent whole-genome sequencing at the central laboratory, and were analyzed using open-source bioinformatic tools. MDRO burden and transmission were assessed using combined genomic and epidemiologic data.

In total, 408 isolates were collected from 358 patients; 47.5% were screening isolates. ESBL-Ec was most common (52.5%), then MRSA (21.6%), vanA VRE (15.7%), and ESBL-Kp (7.6%). Most MDROs (88.3%) were isolated from patients with recent healthcare exposure.

Combining genomics and epidemiology identified that at least 27.1% of MDROs were likely acquired in a hospital; most of these transmission events would not have been detected without genomics. The highest proportion of transmission occurred with vanA VRE (88.4% of patients).

Genomic and epidemiologic data from multiple institutions can feasibly be combined prospectively, providing substantial insights into the burden and distribution of MDROs, including in-hospital transmission. This analysis enables infection control teams to target interventions more effectively.

Surgical antimicrobial prophylaxis (SAP) is commonly administered in orthopedic procedures. Research regarding SAP appropriateness for specific orthopedic procedures is limited and is required to facilitate targeted orthopedic prescriber behavior change.

To describe SAP prescribing and appropriateness for orthopedic procedures in Australian hospitals.

Multicenter, national, quality improvement study with retrospective analysis of data collected from Australian hospitals via Surgical National Antimicrobial Prescribing Survey (Surgical NAPS) audits from January 1, 2016, to April 15, 2019, were analyzed.

Logistic regression identified hospital, patient and surgical factors associated with appropriateness. Adjusted appropriateness was calculated from the multivariable model. Additional subanalyses were conducted on smaller subsets to calculate the adjusted appropriateness for specific orthopedic procedures.

In total, 140 facilities contributed to orthopedic audits in the Surgical NAPS, including 4,032 orthopedic surgical episodes and 6,709 prescribed doses. Overall appropriateness was low, 58.0% (n = 3,894). This differed for prescribed procedural (n = 3,978, 64.7%) and postprocedural doses (n = 2,731, 48.3%). The most common reasons for inappropriateness, when prophylaxis was required, was timing for procedural doses (50.9%) and duration for postprocedural prescriptions (49.8%). The adjusted appropriateness of each orthopedic procedure group was low for procedural SAP (knee surgery, 54.1% to total knee joint replacement, 74.1%). The adjusted appropriateness for postprocedural prescription was also low (from hand surgery, 40.7%, to closed reduction fractures, 68.7%).

Orthopedic surgical specialties demonstrated differences across procedural and postprocedural appropriateness. The metric of appropriateness identifies targets for quality improvement and is meaningful for clinicians. Targeted quality improvement projects for orthopedic specialties need to be developed to support optimization of antimicrobial use.

To determine the prevalence of antibiotic allergy labels (AALs) in Australian aged care residents and to describe the impact of labels on antibiotic prescribing practices.

Point-prevalence survey.

Australian residential aged care facilities.

We surveyed 1,489 residents in 407 aged care facilities.

Standardized data were collected on a single day between June 1 and August 31, 2018, for residents prescribed an antibiotic. An AAL was reported if it was documented in the resident’s health record. Resident-level data were used to calculate overall prevalence, and antibiotic-level data were used to report relative frequency of AALs for individual antibiotics and classes.

Among 1,489 residents, 356 (24%) had 1 or more documented AALs. The AALs for penicillin (28.3%), amoxicillin or amoxicillin/clavulanic acid (10.5%), cefalexin (7.2%), and trimethoprim (7.0%) were most commonly reported. The presence of an AAL was associated with significantly less prescribing of penicillins (OR, 0.43; 95% CI, 0.31–0.62; P < .001) and significantly more prescribing of lincosamides (OR, 4.81; P < .001), macrolides (OR, 2.03; P = .007), and tetracyclines (OR, 1.54; P = .033). Of residents with AALs, 7 residents (1.9%) were prescribed an antibiotic that was listed on the allergy section of their health record.

A high prevalence of AALs was observed among residents of Australian aged care facilities, comparable to the prevalence of AALs in high-risk hospitalized patients. Significant increases in prescribing of lincosamide, macrolide, and tetracycline agents poses a potential risk to aged populations, and future studies must evaluate the benefits of AAL delabelling programs tailored for aged care settings.

To evaluate time trends in surgical site infection (SSI) rates and SSI pathogens in Australia.

Prospective multicenter observational cohort study.

A group of 81 Australian healthcare facilities participating in the Victorian Healthcare Associated Infection Surveillance System (VICNISS).

All patients underwent surgeries performed between October 1, 2002, and June 30, 2013. National Healthcare Safety Network SSI surveillance methods were employed by the infection prevention staff at the participating hospitals.

Procedure-specific risk-adjusted SSI rates were calculated. Pathogen-specific and antimicrobial-resistant (AMR) infections were modeled using multilevel mixed-effects Poisson regression.

A total of 183,625 procedures were monitored, and 5,123 SSIs were reported. Each year of observation was associated with 11% risk reduction for superficial SSI (risk ratio [RR], 0.89; 95% confidence interval [CI], 0.88–0.90), 9% risk reduction for deep SSI (RR, 0.91; 95% CI, 0.90–0.93), and 5% risk reduction for organ/space SSI (RR, 0.95; 95% CI, 0.93–0.97). Overall, 3,318 microbiologically confirmed SSIs were reported. Of these SSIs, 1,174 (35.4%) were associated with orthopedic surgery, 827 (24.9%) with coronary artery bypass surgery, 490 (14.8%) with Caesarean sections, and 414 (12.5%) with colorectal procedures. Staphylococcus aureus was the most frequently identified pathogen, and a statistically significant increase in infections due to ceftriaxone-resistant Escherichia coli was observed (RR, 1.37; 95% CI, 1.10–1.70).

Standardized SSI surveillance methods have been implemented in Victoria, Australia. Over an 11-year period, diminishing rates of SSIs have been observed, although AMR infections increased significantly. Our findings facilitate the refinement of recommended surgical antibiotic prophylaxis regimens and highlight the need for a more expansive national surveillance strategy to identify changes in epidemiology.

Infect Control Hosp Epidemiol 2015;00(0): 1–8

To measure the interobserver agreement, sensitivity, specificity, positive predictive value, and negative predictive value of data submitted to a statewide surveillance system for identifying central line-associated bloodstream infection (BSI).

Retrospective review of hospital medical records comparing reported data with gold standard according to definitions of central line–associated BSI.

Six Victorian public hospitals with more than 100 beds.

Reporting of surveillance outcomes was undertaken by infection control practitioners at the hospital sites. Retrospective evaluation of the surveillance process was carried out by independent infection control practitioners from the Victorian Hospital Acquired Infection Surveillance System (VICNISS). A sample of records of patients reported to have a central line-associated BSI were assessed to determine whether they met the definition of central line–associated BSI. A sample of records of patients with bacteremia in the intensive care unit during the assessment period who were not reported as having central line–associated BSI were also assessed to see whether they met the definition of central line-associated BSI.

Records of 108 patients were reviewed; the agreement between surveillance reports and the VICNISS assessment was 67.6% (κ = 0.31). Of the 46 reported central line–associated BSIs, 27 were confirmed to be central line–associated BSIs, for a positive predictive value of 59% (95% confidence interval [CI], 43%–73%). Of the 62 cases of bacteremia reviewed that were not reported as central line–associated BSIs, 45 were not associated with a central line, for a negative predictive value of 73% (95% CI, 60%–83%). Estimated sensitivity was 35%, and specificity was 87%. The positive likelihood ratio was 3.0, and the negative likelihood ratio was 0.72.

The agreement between the reporting of central line–associated BSI and the gold standard application of definitions was unacceptably low. False-negative results were problematic; more than half of central line–associated BSIs may be missed in Victorian public hospitals.