Controlled human infection (CHI) models can provide insights into transmission of pathogens such as Streptococcus pyogenes (Strep A). As part of the Controlled Human Infection with Penicillin for Streptococcus pyogenes (CHIPS) trial, we explored the potential for transmission among participants deliberately infected with the Strep A emm75 strain. Three approaches to understanding transmission were employed: the use of agar settle plates to capture possible droplet or airborne spread of Strep A; measurement of distance droplets could spread during conversation; and environmental swabbing of high-touch items to detect Strep A on surfaces. Of the 60 (27%) CHIPS trial participants across five cohorts, 16 were enrolled in this sub-study; availability of study staff was the primary reason for selection. In total, 189 plates and 260 swabs were collected. Strep A was grown on one settle plate from a participant on the second day, using plates placed 30 cm away. This participant received the placebo dose of penicillin and had met the primary endpoint of pharyngitis. Whole-genome sequencing identified this to be the challenge strain. Strep A was not detected on any swabs. In this small sample of CHI participants, we did not find evidence of Strep A transmission by the airborne route or fomites, and just one instance of droplet spread while acutely symptomatic with streptococcal pharyngitis. Although these experiments provide evidence of minimal transmission within controlled clinical settings, greater efforts are required to explore Strep A transmission in naturalistic settings.IMPORTANCEStreptococcus pyogenes remains a significant driver of morbidity and mortality, particularly in under-resourced settings. Understanding the transmission modalities of this pathogen is essential to ensuring the success of prevention methods. This proposed paper presents a nascent attempt to determine the transmission potential of Streptococcus pyogenes nested within a larger controlled human infection model.

Objective: To explore the impact of COVID-19 pandemic disruptions on general practice trainees interdependent learning, from the perspectives of trainees and the whole of the practice team.

Setting: Four rural general practices in Queensland that continued to supervise registrars, junior doctors and medical students through the pandemic.

Participants: Twenty-three members of the general practice teams, including general practitioners, practice managers, receptionists, practice nurses, registrars, junior doctors and medical students.

Design: Audio-recorded semi-structured interviews were conducted with all participants following an initial survey. Thematic analysis and the theory of interdependent learning were used to understand how supervision and training was both disrupted and sustained during the pandemic period. Reporting is informed by the Consolidated Criteria for Reporting Qualitative Research (COREQ) guidelines.

Results: Learning affordances were transformed by the rapid implementation of physical distancing and other infection control measures. Telehealth consultations and remote working impacted on the interdependent relationship between the work environment, supervision team and trainees.

Conclusion: Practice staff identified new ways of working that arose through this period, including changes to practice team roles and the supervisory dynamic that enabled patient care and trainee learning to continue. Social connectedness was important to the trainees and the implications for future training need to be further evaluated.

Background: Many patients with hematological malignancy develop fever after chemotherapy/conditioning but before chemotherapy-induced neutropenia (preneutropenic fever [PNF]). The proportion of PNF with an infectious etiology is not well established.

Methods: We conducted a single-center, prospective observational substudy of PNF (neutrophils >0.5 cells/μL, ≥38.0°C) in adults receiving acute myeloid leukemia (AML) chemotherapy, or allogeneic hematopoietic cell transplant (allo-HCT) conditioning enrolled in a neutropenic fever randomized controlled trial between 1 January and 31 October 2018. Eligible patients had anticipated neutropenia ≥10 days and exclusions included concurrent infection and/or neutropenia prior to chemotherapy or conditioning. PNF rates and infections encountered were described. Associations between noninfectious etiologies and fever were explored. Antimicrobial therapy prescription across preneutropenic and neutropenic periods was examined.

Results: Of 62 consecutive patients included (43 allo-HCT, 19 AML), 27 had PNF (44%) and 5 (19%) had an infective cause. Among allo-HCT, PNF occurred in 14 of 17 (82%) who received thymoglobulin; only 1 of 14 (7%) had infection. During AML chemotherapy, 18 of 19 received cytarabine, of which 8 of 18 (44%) had PNF and 3 of 8 (38%) had infection. Most patients with PNF had antimicrobial therapy continued into the neutropenic period (19/27 [70%]). Those with PNF were more likely to be escalated to broader antimicrobial therapy at onset/during neutropenic fever (5/24 [21%] vs 2/30 [7%]).

Conclusions: Rates of PNF were high, and documented infection low, leading to prolonged and escalating antimicrobial therapy. In the absence of infection, early cessation of empiric therapy after PNF is recommended as an important stewardship intervention.

Background: Procalcitonin (PCT) is a blood marker used to help diagnose bacterial infections and guide antibiotic treatment. PCT testing was widely used/adopted during the COVID-19 pandemic in the UK.

Objectives: Primary: to measure the difference in length of early (during first 7 days) antibiotic prescribing between patients with COVID-19 who did/did not have baseline PCT testing during the first wave of the pandemic. Secondary: to measure differences in length of hospital/ICU stay, mortality, total days of antibiotic prescribing and resistant bacterial infections between these groups.

Methods: Multi-centre, retrospective, observational, cohort study using patient-level clinical data from acute hospital Trusts/Health Boards in England/Wales. Inclusion: patients ≥16 years, admitted to participating Trusts/Health Boards and with a confirmed positive COVID-19 test between 1 February 2020 and 30 June 2020.

Results: Data from 5960 patients were analysed: 1548 (26.0%) had a baseline PCT test and 4412 (74.0%) did not. Using propensity-score matching, baseline PCT testing was associated with an average reduction in early antibiotic prescribing of 0.43 days [95% confidence interval (CI): 0.22-0.64 days, P < 0.001) and of 0.72 days (95% CI: 0.06-1.38 days, P = 0.03] in total antibiotic prescribing. Baseline PCT testing was not associated with increased mortality or hospital/ICU length of stay or with the rate of antimicrobial-resistant secondary bacterial infections.

Conclusions: Baseline PCT testing appears to have been an effective antimicrobial stewardship tool early in the pandemic: it reduced antibiotic prescribing without evidence of harm. Our study highlights the need for embedded, rapid evaluations of infection diagnostics in the National Health Service so that even in challenging circumstances, introduction into clinical practice is supported by evidence for clinical utility.

Study registration number: ISRCTN66682918.

Aim: In 2021, infection control guidelines, including those specific to feeding environments, were introduced by the International Olympic and Paralympic Committees to reduce virus transmission at the Tokyo 2020 Summer and Beijing 2022 Winter games. This observational cross-sectional study aimed to investigate caterers' compliance to these guidelines which included measures for personal hygiene, sanitisation, and physical distancing at these events.

Methods: Expert sport dietitians attending Tokyo (n = 15) and Beijing (n = 7) games were surveyed to rate 11 COVID-19 countermeasures as fully (100%), partially or non-compliant at nine dining locations across both events. Descriptive analysis of each countermeasure based on observed compliance and location was conducted and reported as a proportion of the total responses. To better understand participant perspectives of the factors influencing compliance, open responses were systematically coded into themes and sub-themes by researchers through content analysis. Themes generated from participant comments were categorised based on their relevance to specific countermeasures and locations to identify commonalities and disparities in participant experiences, perceptions, and observations.

Results: All main dining halls at both events were observed as 100% compliant to countermeasures on more occasions compared with Tokyo's venues and satellite villages. However, Beijing's three main dining halls, showed a greater compliance compared with Tokyo's main dining hall, likely due to overcrowding in Tokyo. Comments suggested that smaller dining spaces, with overcrowding, may have contributed to reduced compliance to physical distancing measures. Food safety concerns were raised about gastrointestinal distress in Beijing due to food cross-contamination.

Conclusion: Findings suggest that the food service environment may influence caterers' abilities to comply with foodservice safety and infection control guidelines. In the post-pandemic era, enhanced quality control and standardised risk mitigation strategies are needed to improve athletes' health at international sporting events.

Background and objectives: Surgical site infection (SSI) after dermatological surgery is associated with poor outcomes. Developing clinical prediction rules based on the predicted probability of infection might encourage guided prophylaxis and judicious prescribing. The purpose of this study was to develop a clinical prediction rule based on identified risk factors for SSI in a large general practice patient cohort.

Method: We examined a large, pooled dataset from four randomised controlled trials performed in a regional centre of North Queensland, Australia. Multivariable logistic regression identified a prediction model. Bootstrapping was used for internal validation. A scoring system was based on predicted probabilities of infection.

Results: The final prediction rule included age >55 years and the anatomical site, histology and complexity of the excision. The area under the curve was 0.704.

Discussion: Our prediction rule encourages judicious use of prophylaxis in clinical practice.

Objectives: The occurrence of infection in the ankle and hindfoot presents a formidable surgical challenge. Currently, there is a lack of consensus regarding its treatment strategies. The purpose of this study was to investigate the outcomes of one-stage arthroscopic ankle and tibiotalocalcaneal (TTC) arthrodesis with external fixation in the treatment of septic ankle and hindfoot arthritis.

Methods: A retrospective consecutive case-series study was conducted involving six patients diagnosed with acute or chronic septic ankle or hindfoot arthritis, who underwent operative intervention entailing thorough debridement, arthroscopically assisted one-stage ankle or TTC fusion, and external fixation. The American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score and visual analog scale (VAS) pain score were determined preoperatively and at the final follow-up. Demographic and clinical data, inclusive of perioperative and postoperative complications, were recorded. Comparisons of AOFAS ankle-hindfoot score and VAS pain score between preoperative measures and those at the final follow-up were conducted using paired t-tests or paired Wilcoxon rank-sum tests.

Results: The study cohort comprised two males and four females, with a mean age of 48.7 years (range, 26-75) at the time of surgical intervention. At the final follow-up (mean, 26.5 months; range, 16-48), the AOFAS scores exhibited a significant improvement, ascending from an initial mean of 38.8 (range, 12-57) to 80.0 (range, 54-92) (p = 0.007). VAS scores indicated a substantial reduction in pain, decreasing from 6.5 (range, 4-9) to 0 (range, 0-5) (p = 0.046). All patients had achieved osseous consolidation, with a hindfoot infection control rate of 100%.

Conclusion: One-stage arthroscopic ankle and TTC arthrodesis with external fixation is as an effective therapeutic choice for septic ankle or hindfoot arthritis. This approach yields favorable outcomes characterized by effective infection control, favorable osseous consolidation, and significant functional restoration of the affected limb.

Introduction: Radiography students complete professional placements in various clinical settings and must adhere to distinct infection prevention and control (IPC) protocols. The aim of this study was to explore radiography students' training, knowledge, attitudes, and practice (KAP) relating to IPC in the use of contrast media injectors in computed tomography (CT).

Methods: An online survey study was undertaken with radiography students enrolled at two Australian universities. Survey questions related to contrast media training and KAP regarding IPC in CT. Data was summarised using descriptive statistics, with comparisons between experience in public and private practice. One free-text response question focused on non-adherence to IPC best practice, analysed using content analysis.

Results: In total, 40 students completed the survey (9% response rate). Reports of IPC and contrast media equipment training was high, with disposition for further training. Regarding IPC knowledge, 65% of students responded correctly to all 'knowledge' items (individual scores range: 60-100%). Low consensus was observed regarding whether gloves replace the need for hand hygiene and if CT contrast tubing poses risk to healthcare workers (85% each). Mean scores ranged from 41% to 100% regarding identification of sterile syringe and tubing components. Responses to the open-ended question were categorised into four themes: 'High non-adherence risk working conditions', 'attitudes and practice', 'knowledge', and 'prioritise good IPC practice'.

Conclusions: Radiography students demonstrate varied comprehension of IPC regarding contrast media equipment, and results suggest need for collaborative efforts between academic institutions and clinical training sites to integrate IPC protocols into curricula and on-site training.

The escalating global burden of antimicrobial resistance (AMR) represents a critical public health challenge. This rise in antibiotic resistance is concomitant with heightened antibiotic consumption, with an estimated annual usage of 100,000 to 200,000 tons. A recent systematic review, which analysed data from 204 countries, reported that AMR was responsible for 4.95 million deaths in 2019 (Murray et al., 2022). The growing threat of AMR is imposing a significant financial burden on the global economy, with the CDC reporting an additional annual cost of $20 billion in the U.S. and €9 billion in Europe. The emerging field of bacteriophage therapy offers promising potential as a game-changer in the era of AMR. However, existing literature reveals numerous research gaps and technological challenges, including insufficient information on phage pharmacology, genomics, and a lack of preclinical and clinical data. In addition to conducting further research to address existing knowledge gaps, establishing phage banks in clinical facilities could be a transformative advancement in the fight against AMR.

Carbapenems are the antibiotics of choice for treating multidrug-resistant bacterial infections. Metallo-β-lactamases (MBLs) are carbapenemases capable of hydrolyzing nearly all therapeutically available beta-lactam antibiotics. Consequently, this research assessed the distribution of two MBL genes and three β-lactamases and their associated phenotypic resistance in diarrheal and urinary-tract infections (UTIs) to guide future policies. Samples were collected through a cross-sectional study, and β-lactamase genes were detected via PCR. A total of 228 diarrheal bacteria were isolated from 240 samples. The most predominant pathogens were Escherichia coli (32%) and Klebsiella spp. (7%). Phenotypic resistance to amoxicillin-clavulanic acid, aztreonam, cefuroxime, cefixime, cefepime, imipenem, meropenem, gentamicin, netilmicin, and amikacin was 50.4%, 65.6%, 66.8%, 80.5%, 54.4%, 41.6%, 25.7%, 41.2%, 37.2%, and 42.9%, respectively. A total of 142 UTI pathogens were identified from 150 urine samples. Klebsiella spp. (39%) and Escherichia coli (24%) were the major pathogens isolated. Phenotypic resistance to amoxicillin-clavulanic acid, aztreonam, cefuroxime, cefixime, cefepime, imipenem, meropenem, gentamicin, netilmicin, and amikacin was 93.7%, 75.0%, 91.5%, 93.7%, 88.0%, 72.5%, 13.6%, 44.4%, 71.1%, and 43%, respectively. Twenty-four diarrheal isolates carried blaNDM-1 or blaVIM genes. The overall MBL gene prevalence was 10.5%. Thirty-six UTI pathogens carried either blaNDM-1 or blaVIM genes (25.4%). Seven isolates carried both blaNDM-1 and blaVIM genes. MBL genes were strongly associated with phenotypic carbapenem and other β-lactam antibiotic resistance. blaOXA imparted significantly higher phenotypic resistance to β-lactam antibiotics. Active surveillance and stewardship programs are urgently needed to reduce carbapenem resistance in Bangladesh.

During the COVID-19 pandemic, changes occurred within the surgical patient population. An increase in the frequency of resistant Gram-negative bacteria has since been recorded worldwide. After the start of the COVID-19 pandemic, microbiological diagnostics in our institution was performed using MALDI-TOF mass spectrometry. With this study, we wanted to confirm whether it contributed to a greater number of pathogenic bacteria detected in surgical ICU patients. A total of 15,033 samples taken from 1781 surgical patients were compared during the period from 2016 to February 2020 and during the COVID-19 pandemic from March 2020 to February 2023. On patients' admission, pathogenic bacteria were mostly isolated from the respiratory system (43.1% and 44.9%), followed by urine cultures (18.4 vs. 15.4%) before and during the pandemic. After the onset of the COVID-19 pandemic, there was a significant increase in the frequency of isolation of Enterobacter spp. (5.4 before vs. 9%, p = 0.014) and other enterobacteria (6.9 vs. 10.8%, p = 0.017) on patients' admission to the ICU, respectively. Despite this change, mortality in the ICU during the post-COVID-19 period was reduced from 23 to 9.6% (p < 0.001). The frequency of bacterial isolation did not change with the application of MALDI-TOF technology. By identifying the microorganism while simultaneously recognizing some resistance genes, we were able to start targeted therapy earlier. With the application of other infection control methods, MALDI-TOF may have contributed to the reduction in mortality in surgical ICU patients during the COVID-19 pandemic.

Background: Surgical headwear is designed to maintain sterility and prevent microbial contamination. However, the environmental impact of the healthcare industry carries an obligation to develop sustainable alternatives. We aim to explore the environmental impact and safety of reusable surgical headwear.

Methods: A systematic review and meta-analysis were performed using MEDLINE, Embase, Scopus, Google Scholar, PubMed, and the Cochrane Library until December 10, 2023. Studies were reviewed for suitability and risk of bias using the ROBINS-I tool, with the results aggregated using Review Manager Version 5.4 for odds ratios (ORs) and 95% confidence intervals (CIs), and the I² was used to assess heterogeneity.

Results: This systematic review included nine studies, and the meta-analysis included six studies involving 45,708 procedural cases. There was no significant difference in surgical site infection (SSI) rates between the reusable and disposable groups (OR: 0.79; 95% CI: 0.59-1.07; P = 0.13). Policy implementation did not affect SSI rates (OR: 1.21; 95% CI: 0.85-1.73; P = 0.30). Reusable surgical head covers demonstrated a significantly lower carbon footprint (P < 0.001), ozone depletion (P < 0.005), fossil fuel depletion (P < 0.005), terrestrial acidification (P < 0.005), and fine particulate matter formation (P < 0.005) than disposable alternatives.

Conclusion: Reusable surgical headwear matches disposable options for SSI incidence and offers environmental advantages. These findings support a shift towards reusable alternatives in healthcare, aligning patient safety with ecological responsibility. By adopting reusable alternatives, healthcare systems can actively contribute to planetary health, thereby highlighting the significant role of sustainable practices in modern medical settings.

Clinical relevance: Antimicrobial stewardship aims to improve how antibiotics are prescribed by clinicians and used by patients, to ensure safe appropriate use, and to prevent and contain antimicrobial resistance.

Background: Australian optometrists can prescribe a range of antimicrobial agents, but to what extent they consider antimicrobial stewardship is not known. This study evaluated what final-year optometry students and optometrists understood about antimicrobial stewardship in eye care and considered relevance to oral prescribing and education.

Methods: A knowledge, attitude, and practice (KAP) questionnaire was developed comprising four sections: i) demographic questions, ii) 10 multiple choice questions regarding Knowledge about antimicrobial agents and likely pathogens, diagnosis, treatment, and preventing resistance, iii) 10 Likert rating scale questions about thoughts and Attitudes, iv) mix of question types (5× MCQ: course of action, 16 Likert scale: confidence) related to Practice (diagnosis, management, and prescribing). Descriptive analyses were conducted (medians, mean±SD, and distributions).

Results: Thirteen students and 36 optometrists completed the survey. Both groups had a good understanding of microbial resistance and antibiotic prescribing for ocular conditions; average knowledge scores were 9.2 ± 0.7 and 8.7 ± 1.1 for students and practitioners, respectively. Scores were neutral to agree for questions related to the need for more educational programs. The answers of practice-related MCQs had a dichotomy of answers indicating a diversity of opinion, as can be the case in practice. Average total practice confidence scores were approximately 57/80 for students and 68/80 for optometrists. Optometrists and students were very confident in their ability to conduct an appropriate case history and use their knowledge and clinical skills, including slit lamp anterior eye assessment. The lowest confidence scores were for conducting microbial testing, i.e. taking swabs for pathology.

Conclusion: Student and optometrist knowledge, attitudes, and practice around antimicrobial stewardship were high and in line with other health professions globally. There is scope for increased stewardship training.

Background: There is little known about antibiotic de-escalation (ADE) practices in the intensive care unit (ICU).

Objective: The objective was to determine the proportion of patients who received ADE within 24 hours of actionable cultures and identify predictors of timely ADE.

Methods: Multicenter cohort study in ICUs of 15 hospitals in Australia and New Zealand. Adult patients were included if they were started on broad-spectrum antibiotics within 24 hours of ICU admission. The ADE was defined as switching from a broad-spectrum agent to a narrower-spectrum agent or antibiotic cessation. The primary outcome was ADE within 24 hours of an actionable culture, where ADE was possible.

Results: The 446 patients included in the study had a mean age of 63 ± 16 years, 60% were male, 32% were mechanically ventilated, and 19% were immunocompromised. Of these, 161 (36.1%) were not eligible for ADE and 37 (8.3%) for whom ADE within 24 hours of actionable culture could not be determined. In the remaining 248 patients, ADE occurred ≤24 hours in 60.5% (n = 150/248) after actionable cultures. In the multivariable logistic regression analysis, ADE was less likely to occur within 24 hours for patients with negative cultures (odds ratio [OR] = 0.48, 95% confidence interval [CI] = 0.25-0.92, P = 0.03).

Conclusion and relevance: Timely ADE may not occur in 40% of patients in the ICU and is less likely to occur in patients with negative cultures. Timely ADE can be improved, and patients with negative cultures should be targeted as part of antimicrobial stewardship efforts.

Background: Despite the burden of pyelonephritis after kidney transplantation, there is no consensus on initial empirical antibiotic management.

Methods: We surveyed clinicians throughout the world on their practice and opinions about the initial empirical therapy of post-transplant pyelonephritis, using clinical vignettes. A panel of experts from 19 countries on six continents designed this survey, and invited 2145 clinicians to participate.

Results: A total of 721 clinicians completed the survey (response rate: 34%). In the hypothetical case of a kidney transplant recipient admitted with pyelonephritis but not requiring intensive care, most respondents reported initiating either a 3rd-generation cephalosporin (37%) or piperacillin-tazobactam (21%) monotherapy. Several patient-level factors dictated the selection of broader-spectrum antibiotics, including having a recent urine culture showing growth of a resistant organism (85% for extended-spectrum ß-lactamase-producing organisms, 90% for carbapenemase-producing organisms, and 94% for Pseudomonas aeruginosa). Respondents attributed high importance to the appropriateness of empirical therapy, which 87% judged important to prevent mortality. Significant practice and opinion variations were observed between and within countries.

Conclusion: High-quality studies are needed to guide the empirical management of post-transplant pyelonephritis. In particular, whether prior urine culture results should systematically be reviewed and considered remains to be determined. Studies are also needed to clarify the relationship between the appropriateness of initial empirical therapy and outcomes of post-transplant pyelonephritis.

The traditional method of monitoring hand hygiene (HH) based on specific indications does not ensure that HH is performed for all required indications during patient care. This study aimed to compare HH performance rates (HHPRs) based on specific indications versus overall patient care among nurses at a university hospital. The study retrospectively analyzed HH monitoring data for 1398 indications from 543 patients and 190 nurses. Observations were conducted continuously, tracking a single healthcare worker from before patient contact until the end of the contact within a 30-min period. The indication-based HHPR was found to be 89.1%, while the patient-based HHPR was 78.1%. In the context of patient-based HHPR, the lowest rates were observed among nurses in the emergency room (48.3%) and those with less than 1 year of work experience (66.7%). Moreover, the largest discrepancy between indication-based and patient-based HHPR was noted among emergency room nurses with less than 1 year of experience. This significant difference underscores the need for patient-based HH monitoring, particularly for nurses in emergency settings and those with limited experience.

Diphtheria is a potentially fatal bacterial infection caused by toxin-producing strains of corynebacteria, most often Corynebacterium diphtheriae and less commonly Corynebacterium ulcerans. Incidence of the disease has fallen significantly since the introduction of vaccination programs; it is now rare in countries with high vaccination coverage such as Australia. This article presents the most recent respiratory cases of diphtheria in two children in New South Wales-the first locally acquired childhood cases in Australia in 30 years-and discusses potential contributing factors. These encompass the lack of clinical awareness and the delays in laboratory diagnosis in regional laboratories. The cases also highlight the problem of vaccine hesitancy and the role that primary carers play in addressing these anxieties. While clinical management of the cases progressed well, factors in the public health responses were complicated by access to appropriate care and by delays in antibiotic sensitivity profiles. The public health response to these cases raises important considerations for clinicians and public health practitioners, including preparedness for rare and re-emerging diseases, the need for culturally safe environments and the importance of addressing vaccine hesitancy. Preparedness requires consideration of the capacity of regional health systems with fewer resources and of how public health departments can support response to multiple crises. Preparedness also relies on access to necessary diagnostic laboratory resources, on up-to-date guidelines, and on maintaining awareness among clinicians for these rare infections.