Canada communicable disease report = Releve des maladies transmissibles au Canada最新文献

Background: The National Advisory Committee on Immunization (NACI) reviews the evolving evidence on influenza immunization and provides annual recommendations regarding the use of seasonal influenza vaccines. The NACI Statement on seasonal influenza vaccines for 2025-2026 updates the NACI recommendations from the previous year.

Objective: To summarize the 2025-2026 NACI seasonal influenza vaccine recommendations and to highlight new and updated information.

Methods: For the development of the Statement on seasonal influenza vaccines for 2025-2026, the NACI Influenza Working Group applied the NACI evidence-based process to assess available evidence and formulate recommendations. These recommendations were evaluated and approved by NACI based on the available evidence.

Results: Key updates for the 2025-2026 influenza season include: 1) removal of the preferential recommendation for quadrivalent influenza vaccines in children; 2) reiteration of the safety of concurrent administration of seasonal influenza vaccines and other vaccines, including COVID-19, based on updated evidence; 3) new evidence on the protective effects of influenza vaccination on cardiovascular events; 4) updated language for Indigenous populations; and 5) addition of individuals at higher risk of avian influenza A(H5N1) exposure as a group for whom influenza vaccination is particularly important.

Conclusion: NACI recommends that seasonal influenza vaccine should be offered annually to anyone six months of age and older who does not have a contraindication to the vaccine. Influenza vaccination is particularly important for people at high risk of influenza-related complications or hospitalization, people capable of transmitting influenza to those at high risk, and others as outlined in the Statement.

Background: Outcome surveillance is an important component of infection prevention and control (IPAC) programs to guide healthcare decisions. It is crucial that the reported data are of the highest quality. Reviewing completeness, accuracy and timeliness of the data is important to reduce data inconsistencies. However, many IPAC staff do not have training in data cleaning or data quality activities.

Methods: Expert epidemiologists across Canada have created best practice guidance for data quality activities to provide sufficient detail to improve this important patient safety activity. Most of these activities are simple checks to review the accuracy of the data without requiring additional review of the patient record or linkage to other datasets.

Results: Based on consensus by surveillance experts across jurisdictions, comprehensive recommendations for data quality in IPAC surveillance programs were developed to improve completeness (22%), accuracy (68%), and timeliness (10%) of the data.

Conclusion: The data quality activities list may be used in Canadian IPAC surveillance activities to support or improve existing surveillance data quality activities for IPAC programs.

Background: People who inject drugs are disproportionately affected by HIV and hepatitis C infections. Estimating the size and distribution of this population is essential in monitoring infectious diseases rates and progress towards elimination.

Objective: This study aims to estimate the population sizes of people in Canada who have ever injected drugs, stratified by sex (assigned at birth), province/region and steroid injection, and those who have recently injected drugs (past 12 months), stratified by sex and steroid injection. While a previous national study reported estimates of recent injection by province, this study provides the first estimates of people who have ever injected drugs at both the national and provincial/regional levels. It is also the first to incorporate stratification by sex and steroid injection, using the most currently available data.

Methods: Using combined cycles (2017-2021) of the Canadian Community Health Survey (CCHS), a nationally representative population-based survey, we applied the weighted prevalence of injection drug use to the 2021 Statistics Canada national population size estimate of individuals aged 15 years or more. To this, further adjustments were made using additional data to account for populations not sampled in the CCHS and under-reporting of injection drug use in surveys.

Results: In 2021, an estimated 388,400 (95% CI: 338,900-436,500) people in Canada had ever injected drugs, representing 1.22% of the Canadian population 15 years of age and older. Among these, 75% were male and 25% were female. These estimates varied across regions, ranging from 0.92% to 2.47%. The estimated number of people who have recently injected drugs was 100,300 (95% CI: 82,300-119,200) or 0.31% of the population, of which 74% were male and 26% were female.

Conclusion: Estimates of people who inject drugs at the national and provincial/regional levels can be used to track key epidemiological metrics that inform public health policy and programming.

Background: There is a growing body of evidence on the potential benefit of influenza vaccination against the occurrence of cardiovascular (CV) events.

Objective: This umbrella review of systematic reviews and meta-analyses (SRMAs) aims to summarize the available evidence on the risk of CV events in adults after receipt of influenza vaccine.

Methods: Four electronic databases were searched (CINAHL, PubMed, SYSVAC and Cochrane Library) for SRMAs published in English or French, between January 1, 2000, and January 14, 2025. Eligible SRMAs included those with a quantitative synthesis of data examining the association between influenza vaccination and the risk of CV events in adults. Data from the included SRMAs were extracted using predefined variables. The quality of each SRMA was assessed by two independent reviewers using the AMSTAR 2 tool.

Results: The review included 25 SRMAs published between 2012 and 2024. Overall, 15 SRMAs were deemed to be of moderate or high quality and were further considered in the evidence synthesis. The most frequently evaluated clinical outcomes were myocardial infarction (MI), all-cause and CV mortality, and major adverse cardiovascular events (MACE). In vaccinated individuals at high-risk for CV events, the risk of CV death was significantly reduced by 23% to 47%, MACE by 26% to 37%, MI by 29% to 34%, and stroke by 13% to 19% compared to unvaccinated individuals.

Conclusion: High-quality evidence from the existing literature supports influenza vaccination as an effective preventive measure for reducing CV disease burden. Highlighting this benefit to patients could increase vaccine uptake and improve both influenza and CV outcomes, especially where coverage remains suboptimal.

Over the past 20 years, Trichophyton mentagrophytes (T. mentagrophytes) infections affecting the genital and pubic regions, with suspected sexual transmission, have been increasingly reported in South Asia and Europe. The first case in the United States was reported in 2024. We describe the first confirmed case of T. mentagrophytes genotype VII infection causing Majocchi granuloma in a Canadian male who had recently travelled to Mexico, with suspected sexual transmission. Raising awareness among healthcare professionals is critical for early diagnosis and preventing long-term sequelae. Tinea corporis presenting with deep lesions in the pubogenital region and not responding to topical medications should prompt consideration of sexually transmitted fungal infection and extended testing including molecular identification by DNA sequencing of fungal cultures.

Background: Antimicrobial resistance (AMR) is one of the major public health threats of our time. Human activities across the One Health spectrum, such as the misuse and overuse of antimicrobials, can accelerate the resistance threat. A variety of antimicrobials used in veterinary medicine are also important in human medicine. As part of Canada's commitment to address AMR and antimicrobial use (AMU), and to align with international best practices aimed to minimize the impacts of AMR and preserve the effectiveness of existing antimicrobials, regulatory controls and enhanced surveillance initiatives have been implemented in veterinary medicine and animal health to improve intelligence on the quantities of antimicrobials available for use in animals. These efforts include the implementation of the national Veterinary Antimicrobial Sales Reporting (VASR) system in Canada, in 2018. The focus of this article is to describe the VASR data collection system and platform.

Methods: A custom-built data collection and analytical system was developed to enhance understanding of the volume of antimicrobials available for use in animals and contribute to the broader surveillance of trends in AMU and AMR in an effort to support stewardship. Partners from Health Canada's Veterinary Drugs Directorate, the Public Health Agency of Canada's Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, and the Canadian Network for Public Health Intelligence worked together to envision, develop, and implement the national-scale, purpose-built technological intervention, the VASR system.

Results: The VASR surveillance system provides a robust data collection and analytical informatics platform to improve intelligence on antimicrobial sales available for veterinary use in Canada.

Conclusion: An innovative, purpose-built national antimicrobial sales reporting system was developed. This web-based platform is effective for data submission by the participants and facilitates analysis to provide a comprehensive picture of medically important antimicrobials available for use in animals in Canada, thereby supporting AMR and AMU surveillance and stewardship.

Background: The COVID-19 antiviral Nirmatrelvir/Ritonavir (Paxlovid^TM, N/R) was approved for use in Canada in January 2022, with the Government of Canada assuming a procurement role and provinces, territories, and federal departments implementing usage within their respective healthcare systems. The objective of this analysis is to describe how N/R was implemented across various jurisdictions in the first six months after it was available for use and identify promising implementation practices.

Methods: Fourteen semi-structured discussions in small group settings were conducted with jurisdictional representatives involved in the implementation of N/R. A descriptive analysis of the eligibility criteria and service delivery model was conducted. A thematic analysis using the Consolidated Framework for Implementation Research and cluster analysis of the codes were then undertaken on NVivo 12 to identify key themes.

Results: Overall, the eligibility criteria were similar across jurisdictions, and three types of service delivery models were identified. Ten main themes emerged as facilitators and eight as challenges to the implementation. Partnership, collaboration, communication and flexibility were among the facilitators identified, while the complexity of the intervention (e.g., drug-drug interactions), perceived evidence gaps in effectiveness by prescribers, and resource limitations were identified as key implementation challenges.

Conclusion: While there were jurisdictional variations in the implementation of N/R, communication and collaboration, and the availability of rapid testing for COVID-19 emerged as key facilitators. Drug-drug interactions, resource pressures and limited evidence were some of the key challenges. Overall, these facilitators and challenges were similar across jurisdictions and may help inform future therapeutic implementation plans for pandemic preparedness.

Background: In Canada, the burden of gonorrhea has been increasing steadily over the last decade with emerging multi-drug-resistant strains. There is a high genomic similarity between Neisseria meningitidis and Neisseria gonorrhoea.

Methods: Review of published studies and on-going trials with the four-component meningococcal serogroup B vaccine (4CMenB-Bexsero®).

Results: Observational studies have shown protection against gonorrhea infection ranging from 35% to 59% for up to three years after the administration of 4CMenB. Several randomized clinical trials are also under way. Results from the DOXYVAC trial have been published but the sample size was too small to exclude a protective effect in the 30%-50% range. Recommendations on the use of 4CMenB for individuals at high risk of gonorrhea infection have been issued in the United Kingdom and New York state based on results of observational studies.

Conclusion: If results of observational studies are confirmed by randomized trials with an acceptable cost-effectiveness profile in the Canadian context, a targeted immunization program using 4CMenB could be implemented.

Background: Respiratory syncytial virus (RSV) surged in the 2022-2023 respiratory season after low activity during the pandemic. To monitor the RSV season in real time and support healthcare planning, Ontario introduced daily hospital bed census reporting of RSV hospitalizations by age group (0-17, 18-64, 65 years and older).

Objectives: To assess the completeness and quality of the newly introduced real-time surveillance compared to end-of-season ICD-10 coded hospitalization discharge abstract data (DAD) from November 22, 2022, to March 31, 2023.

Methods: Respiratory syncytial virus hospitalizations from both data sources were compared to RSV laboratory positivity to assess concordance with overall RSV activity. A longitudinal comparison by age group was assessed by time-lagged cross-correlation of the daily submission data versus DAD data, including cross correlation coefficients for each time lag, confidence bound and the highest correlation value.

Results: Both data sources followed trends in RSV positivity. Data by age groups showed an early peak of paediatric admissions followed by a peak in adult and older adult hospitalizations. Daily surveillance consistently underestimated hospitalizations with a peak of 430 beds by DAD on January 7, 2023, versus 322 beds (75%) for daily reporting on the same day. The maximum correlation coefficient values were 0.67 (all ages), 0.57 (0-17 years), 0.66 (18-64 years) and 0.63 (65 years and older).

Conclusion: Implementation of daily hospital reporting provided accurate trending in RSV hospitalizations by age group to inform within season healthcare and public health planning.

Background: In Canada in 2020, the indication for use of Imvamune was expanded to include immunization against smallpox, mpox and related Orthopoxvirus infection and disease in adults who are 18 years of age and older and determined to be at high risk for exposure.

Methods: Since the introduction of this new use for the vaccine and throughout the 2022 mpox outbreaks, the Public Health Agency of Canada (PHAC) has closely monitored the safety of the Imvamune vaccine through the Canadian Adverse Events Following Immunization Surveillance System (CAEFISS).

Results: This article describes reports of adverse events following immunization (AEFI) after administration of Imvamune, submitted to the CAEFISS database between May 24, 2022 and December 11, 2022, during the activation of Canada's emergency response.

Conclusion: Monitoring of AEFI reports following immunization with Imvamune submitted to CAEFISS has not identified any new or unexpected safety concerns in the Canadian adult population. The Public Health Agency of Canada continues to monitor for potential vaccine safety signals.