Did the healthcare vaccine mandate work? An evaluation of the impact of the COVID-19 vaccine mandate on vaccine uptake and infection risk in a large cohort of Canadian healthcare workers.

BACKGROUND: We aimed to evaluate the impact of healthcare vaccine mandates on vaccine uptake and infection risk in a cohort of Canadian healthcare workers (HCWs). METHODS: We conduct interrupted time series analysis through a regression discontinuity in time approach to estimate the immediate and delayed impact of the mandate. Multi-level mixed effect modelling fitted with restricted maximum likelihood was used to estimate impact on infection risk. RESULTS: The immediate and sustained effects of the mandate was a 0.19% (p <0.05) and a 0.012% (p <0.05) increase in the daily proportion of unvaccinated HCWs getting their first dose, respectively. An additional 623 (95% confidence interval (CI): 613 - 667) HCWs received first doses compared to the predicted uptake absent the mandate. Adjusted test positivity declined by 0.053% (95% CI: 0.035%,0.069) for every additional day the mandate was in effect. DISCUSSION: Our results indicate that the mandate was associated with significant increases in vaccine uptake and infection risk reduction in the cohort. CONCLUSIONS: Given the benefit that vaccination could bring to HCWs, understanding strategies to enhance uptake is crucial for bolstering health system resilience, but steps must be taken to avert approaches that sacrifice trust, foster animosity, or exacerbate staffing constraints for short-term results.

Adherence to stewardship recommendations for antibiotic discontinuation reduces antibiotic-associated adverse drug events.

Inappropriate antibiotic use may lead to increased adverse drug events (ADEs). This study assessed whether an antimicrobial stewardship recommendation to discontinue antibiotics in patients with low likelihood for bacterial infection reduced antibiotic duration and antibiotic-associated ADEs. At a 4-hospital system, hospitalized adult patients receiving empiric antibiotics for suspected infection were identified between May 2, 2016 and June 30, 2018. For those patients who were deemed unlikely to have a bacterial infection, a note was left by an infectious diseases physician recommending antibiotic discontinuation. Patient cases were considered "adherent" to recommendations if antibiotics were discontinued within 48 hours of the note and "non-adherent" to recommendations if antibiotics were continued beyond this. Duration of antibiotics and potential antibiotic-associated ADEs were collected retrospectively. Attribution of the adverse event to the antibiotic was decided upon by the investigators. The incidence of ADEs and duration of antibiotics between the adherent and non-adherent groups were compared. Of 253 patients deemed unlikely to have a bacterial infection, 114 (45%) treatment teams stopped antibiotics within 48 hours of the recommendation, and 139 (55%) continued antibiotics. The total number of ADEs was significantly higher in the non-adherent group compared to the adherent group (34 ADEs vs 9 ADEs, P = .001). The median number of total prescribed antibiotic days was higher in the non-adherent group than in the adherent group (5 days vs 1 day, P < .001). This study demonstrates that stewardship programs may prevent ADEs by recommending antibiotic discontinuation in patients with low suspicion for bacterial infection.

Vaccination, time lost from work, and COVID-19 infections: a Canadian healthcare worker retrospective cohort study.

The COVID-19 pandemic highlighted hurdles for healthcare delivery and personnel globally. Vaccination has been an important tool for preventing severe illness and death in healthcare workers (HCWs) as well as the public at large. However, vaccination has resulted in some HCWs requiring time off work post-vaccination to recover from adverse events. We aimed to understand which HCWs needed to take time off work post-vaccination, for which vaccine types and sequence, and how post-vaccination absence impacted uptake of booster doses in a cohort of 26,267 Canadian HCWs. By March 31, 2022, more than 98% had received at least two doses of the approved COVID-19 vaccines, following a two-dose mandate. We found that recent vaccination and longer intervals between doses were associated with significantly higher odds of time-loss, whereas being a medical resident and receiving the BNT162b2 vaccine were associated with lower odds. A history of lab-confirmed SARS-CoV-2 infection was associated with lower odds of receiving a booster dose compared with no documented infection, aOR 0.61 (95% CI: 0.55, 0.68). Similarly, taking sick time following the first or second dose was associated with lower odds of receiving a booster dose, aOR 0.83 (95% CI: 0.75, 0.90). As SARS-CoV-2 becomes endemic, the number and timing of additional doses for HCWs requires consideration of prevention of illness as well as service disruption from post-vaccination time-loss. Care should be taken to ensure adequate staffing if many HCWs are being vaccinated, especially for coverage for those who are more likely to need time off to recover.

Urban-rural divide in COVID-19 infection and vaccination rates in healthcare workers in British Columbia, Canada.

Introduction: Healthcare workers (HCWs) play a critical role in responding to the COVID-19 pandemic. Early in the pandemic, urban centres were hit hardest globally; rural areas gradually became more impacted. We compared COVID-19 infection and vaccine uptake in HCWs living in urban versus rural locations within, and between, two health regions in British Columbia (BC), Canada. We also analysed the impact of a vaccine mandate for HCWs. Methods: We tracked laboratory-confirmed SARS-CoV-2 infections, positivity rates and vaccine uptake in all 29,021 HCWs in Interior Health (IH) and all 24,634 HCWs in Vancouver Coastal Health (VCH), by occupation, age and home location, comparing to the general population in that region. We then evaluated the impact of infection rates as well as the mandate on vaccination uptake. Results: While we found an association between vaccine uptake by HCWs and HCW COVID-19 rates in the preceding 2-week period, the higher rates of COVID-19 infection in some occupational groups did not lead to increased vaccination in these groups. By 27 October 2021, the date that unvaccinated HCWs were prohibited from providing healthcare, only 1.6% in VCH compared with 6.5% in IH remained unvaccinated. Rural workers in both areas had significantly higher unvaccinated rates compared with urban dwellers. Over 1800 workers, comprising 6.7% of rural HCWs and 3.6% of urban HCWs, remained unvaccinated and set to be terminated from their employment. While the mandate prompted a significant increase in uptake of second doses, the impact on the unvaccinated was less clear. Conclusions: As rural areas often suffer from under-staffing, loss of HCWs could have serious impacts on healthcare provision as well as on the livelihoods of unvaccinated HCWs. Greater efforts are needed to understand how to better address the drivers of rural-related vaccine hesitancy.

Résumé Introduction: Les travailleurs de la santé (TS) jouent un rôle essentiel dans la réponse à la pandémie de COVID-19. Au début de la pandémie, les centres urbains ont été les plus durement touchés à l'échelle mondiale; les zones rurales ont progressivement été plus touchées. Nous avons comparé l'infection à la COVID-19 et l'adoption du vaccin chez les travailleuses et travailleurs de la santé vivant dans des zones urbaines et rurales au sein de deux régions sanitaires de la Colombie-Britannique (C.-B.), au Canada, et entre ces régions. Nous avons également analysé l'impact d'un mandat de vaccination pour les travailleuses et travailleurs de la santé. Méthodes: Nous avons suivi les infections au SRAS-CoV-2 confirmées en laboratoire, les taux de positivité et l'adoption du vaccin chez les 29 021 TS d'Interior Health (IH) et les 24 634 TS de Vancouver Coastal Health (VCH), par profession, âge et lieu de résidence, en les comparant à la population générale de cette région. Nous avons ensuite évalué l'impact des taux d'infection ainsi que du mandat sur le recours à la vaccination. Résultats: Bien que nous ayons trouvé une association entre l'adoption du vaccin par les TS et les taux de COVID-19 des travailleurs de la santé au cours de la période de deux semaines précédentes, les taux plus élevés d'infection par la COVID-19 dans certains groupes professionnels n'ont pas entraîné une augmentation de la vaccination dans ces groupes. En date du 27 octobre 2021, date à laquelle il était interdit aux travailleuses et travailleurs de santé non vaccinés de fournir des soins de santé, seul 1,6% des travailleuses et travailleurs de la VCH, contre 6,5% des travailleuses et travailleurs de l'IH, n'étaient toujours pas vaccinés. Les travailleuses et travailleurs ruraux des deux zones présentaient des taux de non-vaccination significativement plus élevés que les citadins. Plus de 1 800 travailleuses et travailleurs, soit 6,7% des TS ruraux et 3,6% des TS urbains, n'étaient toujours pas vaccinés et devaient être licenciés. Bien que le mandat ait entraîné une augmentation significative de la prise des deuxièmes doses, l'impact sur les personnes non-vaccinées était moins clair. Conclusions: Comme les zones rurales souffrent souvent d'un manque de personnel, la perte de TS pourrait avoir de graves répercussions sur la prestation des soins de santé ainsi que sur les moyens de subsistance des TS non-vaccinés. Des efforts plus importants sont nécessaires pour comprendre comment mieux aborder les facteurs d'hésitation à SE faire vacciner en milieu rural. Mots-clés: Travailleuses et travailleurs de la santé, COVID-19, vaccination, mandat de vaccination, milieu rural.

A multi-site, international laboratory study to assess the performance of penicillin susceptibility testing of Staphylococcus aureus.

OBJECTIVES: There is clinical uncertainty over the optimal treatment for penicillin-susceptible Staphylococcus aureus (PSSA) infections. Furthermore, there is concern that phenotypic penicillin susceptibility testing methods are not reliably able to detect some blaZ-positive S. aureus. METHODS: Nine S. aureus isolates, including six genetically diverse strains harbouring blaZ, were sent in triplicate to 34 participating laboratories from Australia (n = 14), New Zealand (n = 6), Canada (n = 12), Singapore (n = 1) and Israel (n = 1). We used blaZ PCR as the gold standard to assess susceptibility testing performance of CLSI (P10 disc) and EUCAST (P1 disc) methods. Very major errors (VMEs), major error (MEs) and categorical agreement were calculated. RESULTS: Twenty-two laboratories reported 593 results according to CLSI methodology (P10 disc). Nineteen laboratories reported 513 results according to the EUCAST (P1 disc) method. For CLSI laboratories, the categorical agreement and calculated VME and ME rates were 85% (508/593), 21% (84/396) and 1.5% (3/198), respectively. For EUCAST laboratories, the categorical agreement and calculated VME and ME rates were 93% (475/513), 11% (84/396) and 1% (3/198), respectively. Seven laboratories reported results for both methods, with VME rates of 24% for CLSI and 12% for EUCAST. CONCLUSIONS: The EUCAST method with a P1 disc resulted in a lower VME rate compared with the CLSI methods with a P10 disc. These results should be considered in the context that among collections of PSSA isolates, as determined by automated MIC testing, less than 10% harbour blaZ. Furthermore, the clinical relevance of phenotypically susceptible, but blaZ-positive S. aureus, remains unclear.

Overview and Methods for the Youth Risk Behavior Surveillance System - United States, 2021.

The Youth Risk Behavior Surveillance System (YRBSS) is the largest public health surveillance system in the United States, monitoring a broad range of health-related behaviors among high school students. The system includes a nationally representative Youth Risk Behavior Survey (YRBS) and separate school-based YRBSs conducted by states, tribes, territories, and local school districts. In 2021, these surveys were conducted during the COVID-19 pandemic. The pandemic underscored the importance of data in understanding changes in youth risk behaviors and addressing the multifaceted public health needs of youths. This overview report describes 2021 YRBSS survey methodology, including sampling, data collection procedures, response rates, data processing, weighting, and analyses. The 2021 YRBS participation map, survey response rates, and a detailed examination of student demographic characteristics are included in this report. During 2021, in addition to the national YRBS, a total of 78 surveys were administered to high school students across the United States, representing the national population, 45 states, two tribal governments, three territories, and 28 local school districts. YRBSS data from 2021 provided the first opportunity since the onset of the COVID-19 pandemic to compare youth health behaviors using long-term public health surveillance. Approximately half of all student respondents represented racial and ethnic minority groups, and approximately one in four identified as lesbian, gay, bisexual, questioning, or other (a sexual identity other than heterosexual) (LGBQ+). These findings reflect shifts in youth demographics, with increased percentages of racial and ethnic minority and LGBQ+ youths compared with previous YRBSS cycles. Educators, parents, local decision makers, and other partners use YRBSS data to monitor health behavior trends, guide school health programs, and develop local and state policy. These and future data can be used in developing health equity strategies to address long-term disparities so that all youths can thrive in safe and supportive environments. This overview and methods report is one of 11 featured in this MMWR supplement. Each report is based on data collected using methods presented in this overview. A full description of YRBSS results and downloadable data are available (https://www.cdc.gov/healthyyouth/data/yrbs/index.htm).

Experiences of Unstable Housing Among High School Students - Youth Risk Behavior Survey, United States, 2021.

Youths experiencing unstable housing face higher risks for poor physical, mental, and sexual health outcomes and increased risk for suicide compared with their peers experiencing stable housing. In addition, youths of color and sexual minority youths are disproportionately more likely to experience homelessness. For the first time, in 2021, the nationally representative Youth Risk Behavior Survey included an item assessing housing stability, or nighttime residence among students in grades 9-12 in the United States. During 2021, 2.7% of U.S. high school students experienced unstable housing. Among racial and ethnic subgroups, Native Hawaiian or other Pacific Islander youths were most likely to experience unstable housing, followed by American Indian or Alaska Native and Black youths. Sexual minority (lesbian, gay, bisexual, and questioning or other) youths were more likely to experience unstable housing compared with their heterosexual peers. Compared with students who were stably housed, students who were unstably housed were more likely to engage in risky sexual behaviors, substance use, and suicide ideation and attempts, and to experience violence. These findings highlight which adverse health risks and behaviors are elevated among youths experiencing housing insecurity. Focused public health interventions are required to address the disproportionate burden of health risks prevalent among youths who are unstably housed.

Penicillin de-labelling in vancouver, British Columbia, Canada: comparison of approaches, outcomes and future directions.

BACKGROUND: Inaccurate penicillin allergy labels lead to inappropriate antibiotic prescriptions and harmful patient consequences. System-wide efforts are needed to remove incorrect penicillin allergy labels, but more health services research is required on how to best deliver these services. METHODS: Data was extracted from five hospitals in Vancouver, British Columbia, Canada from October 2018-May 2022. The primary outcomes of this study were to outline de-labelling protocol designs, identify the roles of various healthcare professionals in de-labelling protocols and identify rates of de-labelling penicillin allergies and associated adverse events at various institutions. Our secondary outcome was to describe de-labelling rates for special populations, including pediatric, obstetric and immunocompromised subpopulations. To achieve these outcomes, participating institutions provided their de-labelling protocol designs and data on program participants. Protocols were then compared to find common themes and differences. Furthermore, adverse events were reviewed and percentages of patients de-labelled at each institution and in total were calculated. RESULTS: Protocols demonstrated a high level of variability, including different methods of participant identification, risk-stratification and roles of providers. All protocols used oral and direct oral challenges, heavily involved pharmacists and had physician oversight. Despite the differences, of the 711 patients enrolled in all programs, 697 (98.0%) were de-labelled. There were 9 adverse events (1.3%) with oral challenges with mainly minor symptoms. CONCLUSIONS: Our data demonstrates that de-labelling programs effectively and safely remove penicillin allergy labels, including pediatric, obstetric and immunocompromised patients. Consistent with current literature, most patients with a penicillin allergy label are not allergic. De-labelling programs could benefit from increasing clinician engagement by increasing accessibility of resources to providers, including guidance for de-labelling of special populations.

COVID-19 hospitalisations in immunocompromised individuals in the Omicron era: a population-based observational study using surveillance data in British Columbia, Canada.

Background: People with immune dysfunction are at higher risk of severe outcomes from COVID-19 infection, but relatively little epidemiologic information is available for mostly vaccinated population in the Omicron era. This population-based study compared relative risk of breakthrough COVID-19 hospitalisation among vaccinated people identified as clinically extremely vulnerable (CEV) vs non-CEV individuals before treatment became more widely available. Methods: COVID-19 cases and hospitalisations reported to the British Columbia Centre for Disease Control (BCCDC) between January 7, 2022 and March 14, 2022 were linked with data on their vaccination and CEV status. Case hospitalisation rates were estimated across CEV status, age groups and vaccination status. For vaccinated individuals, risk ratios for breakthrough hospitalisations were calculated for CEV and non-CEV populations matched on sex, age group, region, and vaccination characteristics. Findings: Among CEV individuals, a total of 5591 COVID-19 reported cases were included, among which 1153 were hospitalized. A third vaccine dose with mRNA vaccine offered additional protection against severe illness in both CEV and non-CEV individuals. However, 2- and 3-dose vaccinated CEV population still had a significantly higher relative risk of breakthrough COVID-19 hospitalisation compared with non-CEV individuals. Interpretation: Vaccinated CEV population remains a higher risk group in the context of circulating Omicron variant and may benefit from additional booster doses and pharmacotherapy. Funding: BC Centre for Disease Control and Provincial Health Services Authority.

Masking strategy to protect healthcare workers from COVID-19: An umbrella meta-analysis.

BACKGROUND: The burden of severe disease and death due to SARS-CoV-2 (COVID-19) pandemic among healthcare workers (HCWs) worldwide has been substantial. Masking is a critical control measure to effectively protect HCWs from respiratory infectious diseases, yet for COVID-19, masking policies have varied considerably across jurisdictions. As Omicron variants began to be predominant, the value of switching from a permissive approach based on a point of care risk assessment (PCRA) to a rigid masking policy needed to be assessed. METHODS: A literature search was conducted in MEDLINE (Ovid platform), Cochrane Library, Web of Science (Ovid platform), and PubMed to June 2022. An umbrella review of meta-analyses investigating protective effects of N95 or equivalent respirators and medical masks was then conducted. Data extraction, evidence synthesis and appraisal were duplicated. RESULTS: While the results of Forest plots slightly favoured N95 or equivalent respirators over medical masks, eight of the ten meta-analyses included in the umbrella review were appraised as having very low certainty and the other two as having low certainty. CONCLUSION: The literature appraisal, in conjunction with risk assessment of the Omicron variant, side-effects and acceptability to HCWs, along with the precautionary principle, supported maintaining the current policy guided by PCRA rather than adopting a more rigid approach. Well-designed prospective multi-centre trials, with systematic attention to the diversity of healthcare settings, risk levels and equity concerns are needed to support future masking policies.

Abbott ID NOW™ COVID-19 assay: do not discard the swab.

We compared the performance of ID NOW™ COVID-19 assay nasal swabs with RT-PCR of nasopharyngeal swabs for SARS-CoV-2 in an outbreak setting, determining whether addition of RT-PCR of residual nasal swabs (rNS) (post ID NOW™ elution) would increase overall analytic sensitivity. Devices were placed at 2 long term and 1 acute care sites and 51 participants were recruited. Prospective paired nasopharyngeal and nasal samples were collected for RT-PCR and ID NOW™.  ID NOW™ had a positive and negative categorical agreement of 86% and 93% compared to RT-PCR of nasopharyngeal swabs. Sensitivity and specificity of the ID NOW™ was 86% and 100%, positive and negative predictive value was 100% and 95% (COVID-19 positivity rate: 8%). Addition of rNS RT-PCR increased the positive and negative categorical agreement to 93% and 97%. Based on these results, we propose an alternative workflow which includes complementary testing of rNS on a secondary assay.

A retrospective review of empiric acyclovir prescribing practices for suspected viral central nervous system infections: A single-centre study.

Background: Acyclovir has an important role in the treatment of viral central nervous system (CNS) infection, especially herpes simplex virus (HSV)-1 encephalitis. It is therefore used broadly as empiric therapy for many patients who present to the hospital with symptoms of a possible neurologic infection. We sought to review our practices in acyclovir prescribing, deprescribing, and associated investigations for the clinical syndromes it treats. Methods: Through a retrospective chart review, we identified patients prescribed acyclovir for a possible CNS infection upon admission to Vancouver General Hospital between January 1, 2019, and December 31, 2019. Patient demographics, signs, symptoms, and comorbidities were taken from admission consultation notes or discharge summaries; their investigations, including laboratory tests and imaging, were also recorded. The primary purpose was to describe the appropriateness of empiric acyclovir use in suspected meningoencephalitis cases. Results: Among the 108 patients treated with acyclovir, 94 patients had an indication for starting empiric treatment for encephalitis or meningitis. There was suspicion and workup for encephalitis alone in 76 patients. Among discharge diagnoses, the most common was delirium of a different identified source (18 cases), followed by unknown/other (15 cases). There were seven patients whose CSF viral PCR test was positive for HSV or varicella-zoster virus (VZV); three of them had HSV-1 encephalitis. There were two total adverse events recorded attributed to acyclovir; both cases were of mild acute kidney injury. Conclusion: We found that in many patients, acyclovir was not necessary or could have been stopped earlier, avoiding toxicity and drug costs.

Historique: L'acyclovir joue un rôle important dans le traitement des infections virales du système nerveux central (SNC), notamment l'encéphalite herpétique. Il est donc largement utilisé comme traitement empirique auprès de nombreux patients qui consultent à l'hôpital à cause de symptômes d'éventuelle infection neurologique. Les chercheurs ont révisé leurs pratiques en matière de prescription et de déprescription d'acyclovir ainsi que les examens connexes de syndromes cliniques que traite ce médicament. Méthodologie: Les chercheurs ont procédé à une analyse rétrospective des dossiers pour en extraire les patients à qui on avait prescrit de l'acyclovir à cause d'une éventuelle infection du SNC à leur admission au Vancouver General Hospital entre le 1er janvier et le 31 décembre 2019. Ils ont obtenu la démographie, les signes, les symptômes et les autres maladies des patients dans les notes de consultation à l'admission ou dans les résumés au congé. Ils ont également consigné les examens auxquels les patients ont été soumis, y compris les tests de laboratoire et d'imagerie. L'objectif primaire consistait à décrire le bien-fondé de l'utilisation empirique d'acyclovir en cas de soupçon de méningoencéphalite. Résultats: Chez les 108 patients ayant reçu un traitement à l'acyclovir, 94 présentaient une indication de traitement empirique contre l'encéphalite ou la méningite. Les soupçons et le bilan d'encéphalite seule étaient observés chez 76 patients. Parmi les diagnostics au congé, les plus courants étaient un délire provenant d'une autre source (18 cas), suivi d'un diagnostic inconnu ou autre (15 cas). Chez sept patients, le test PCR du liquide céphalorachidien pour analyser le virus a donné un résultat positif au virus herpès simplex (VHS) ou au virus varicelle-zona, y compris trois cas d'encéphalite à VHS-1. Au total, deux événements indésirables attribués à l'acyclovir ont été consignés, tous deux de lésion rénale aiguë légère. Conclusion: Les chercheurs ont établi que l'aciclovir était inutile ou aurait pu être interrompu plus tôt chez de nombreux patients, ce qui aurait évité la toxicité et réduit les coûts de médicaments.

Vaginal microbiome-host interactions modeled in a human vagina-on-a-chip.

BACKGROUND: A dominance of non-iners Lactobacillus species in the vaginal microbiome is optimal and strongly associated with gynecological and obstetric health, while the presence of diverse obligate or facultative anaerobic bacteria and a paucity in Lactobacillus species, similar to communities found in bacterial vaginosis (BV), is considered non-optimal and associated with adverse health outcomes. Various therapeutic strategies are being explored to modulate the composition of the vaginal microbiome; however, there is no human model that faithfully reproduces the vaginal epithelial microenvironment for preclinical validation of potential therapeutics or testing hypotheses about vaginal epithelium-microbiome interactions. RESULTS: Here, we describe an organ-on-a-chip (organ chip) microfluidic culture model of the human vaginal mucosa (vagina chip) that is lined by hormone-sensitive, primary vaginal epithelium interfaced with underlying stromal fibroblasts, which sustains a low physiological oxygen concentration in the epithelial lumen. We show that the Vagina Chip can be used to assess colonization by optimal L. crispatus consortia as well as non-optimal Gardnerella vaginalis-containing consortia, and to measure associated host innate immune responses. Co-culture and growth of the L. crispatus consortia on-chip was accompanied by maintenance of epithelial cell viability, accumulation of D- and L-lactic acid, maintenance of a physiologically relevant low pH, and down regulation of proinflammatory cytokines. In contrast, co-culture of G. vaginalis-containing consortia in the vagina chip resulted in epithelial cell injury, a rise in pH, and upregulation of proinflammatory cytokines. CONCLUSION: This study demonstrates the potential of applying human organ chip technology to create a preclinical model of the human vaginal mucosa that can be used to better understand interactions between the vaginal microbiome and host tissues, as well as to evaluate the safety and efficacy of live biotherapeutics products. Video Abstract.

Pattern of acquisition of hospital-associated pathogens in the ICU of an academic tertiary care hospital.

BACKGROUND: Among hospitalized patients, a 48-hour window from time of hospitalization defines nosocomial infections and guides empiric antibiotic selection. This time frame may lead to overuse of broad-spectrum antibiotics. Our primary objective was to determine the earliest and median time since hospital admission to acquire antibiotic-resistant pathogens among patients admitted to the intensive care unit (ICU) of an academic, tertiary care hospital. METHODS: Retrospective chart review was conducted for adult patients admitted to the ICU from home or another hospital within the same health authority in 2018, to identify the time to acquisition of hospital-associated pathogens: methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales, non-ESBL ceftriaxone-resistant Enterobacterales, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia. Patients transferred from hospitals outside the health authority, admitted to ICU after 14 days of hospitalization, who were solid organ or bone marrow transplant recipients, or who were otherwise immunocompromised were excluded. RESULTS: In 2018, 1,343 patients were admitted to this ICU; 820 met the inclusion criteria. Of these, 121 (14.76%) acquired a hospital-associated pathogen in the ICU. The probability of isolating a hospital-associated pathogen by 48 hours of hospital admission was 3%. The earliest time to isolate any of these pathogens was 29 hours, and the median was 9 days (interquartile range [IQR] 3.8-15.6 days). CONCLUSIONS: Most patients (85.3%) in this ICU never acquired a hospital-associated pathogen. The median time to acquire a hospital-associated pathogen among the remaining patients suggests that initiating empiric broad-spectrum antibiotics on the basis of a 48-hour threshold may be premature.

HISTORIQUE : Chez les patients hospitalisés, une fenêtre de 48 heures après le moment de l'hospitalisation définit les infections nosocomiales et oriente la sélection d'antibiotiques empiriques. Cette période peut favoriser la surutilisation d'antibiotiques à large spectre. L'objectif primaire de l'étude visait à déterminer la période la plus courte et la période médiane à compter de l'admission pour que les patients admis en soins intensifs à partir d'un hôpital universitaire de soins tertiaires contractent des agents pathogènes antibiorésistants. MÉTHODOLOGIE: Les chercheurs ont procédé à un examen rétrospectif des dossiers des patients adultes admis en soins intensifs à partir de la maison ou d'un autre hôpital de la même autorité sanitaire en 2018, afin de déterminer la période avant de contracter des agents pathogènes associés au milieu hospitalier : Staphylococcus aureus résistant à la méthicilline, entérocoque résistant à la vancomycine, Enterobacterales producteurs de bêta-lactamases à spectre élargi (BLSE), Enterobacterales résistant à la ceftriaxine non producteurs de BLSE, Pseudomonas aeruginosa et Stenotrophomonas maltophilia. Ont été exclus les patients transférés d'un hôpital hors de l'autorité sanitaire, admis en soins intensifs plus de 14 jours après l'hospitalisation, receveurs d'un organe plein ou de moelle osseuse ou autrement immunodéprimés. RÉSULTATS: En 2018, 1 343 patients ont été admis en soins intensifs, dont 820 respectaient les critères d'inclusion. De ce nombre, 121 (14,67 %) ont contracté un agent pathogène en soins intensifs. La probabilité d'isoler un tel agent dans les 48 heures suivant l'admission en milieu hospitalier s'élevait à 3 %. Ces agents pathogènes ont été isolés au plus tôt 29 heures après l'hospitalisation, et au bout d'une période médiane de neuf jours (plage interquartile [PIQ] 3,8 à 15,6 jours). CONCLUSIONS: La plupart des patients (85,3%) de cette unité de soins intensifs n'ont jamais contracté d'agent pathogène associé au milieu hospitalier. Selon la période médiane avant d'acquérir un tel agent pathogène chez les autres patients, il serait prématuré d'entreprendre une antibiothérapie à large spectre au seuil de 48 heures.