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

Background: Respiratory syncytial virus (RSV) is a common respiratory virus. In addition to infants, older adults are at higher risk of severe outcomes due to RSV, particularly advanced-age older adults and those with chronic medical conditions. The authorization of three vaccines, one for adults 50 years of age and older (Arexvy) and two for adults 60 years of age and older (Abrysvo and mRESVIA), offers the opportunity to protect older Canadians from RSV disease. This article summarizes guidance from the National Advisory Committee on Immunization (NACI) on the prevention of RSV in older adults.

Methods: NACI established key policy questions and performed an evidence review and synthesis for three new vaccines. In consideration of the burden of illness to be prevented, safety and efficacy of the new immunizing products, economic evidence and ethics, equity, feasibility and acceptability considerations, NACI made evidence-based recommendations.

Results: The three RSV vaccines may provide similar reductions in hospitalizations associated with RSV and medically attended RSV respiratory tract infection for adults 60 years of age and older. However, evidence is limited for other outcomes. These vaccines were well-tolerated in clinical studies, with an acceptable safety profile among older adults. The duration of protection of the RSV vaccine is not yet known, and it is unclear if the protection offered by vaccination can be boosted by subsequent doses of vaccine.

Conclusion: Based on available evidence, NACI recommends RSV immunization programs for adults 75 years of age and older, particularly for older adults with chronic health conditions who are at increased risk of severe RSV disease. NACI also recommends RSV immunization programs for adults 60 years of age and older who are residents of nursing homes and other chronic care facilities. NACI recommends that receiving an RSV vaccine may be considered as an individual decision by adults 50 to 74 years of age, in consultation with their healthcare provider.

Background: Enteric illnesses are a preventable cause of morbidity and healthcare utilization in Canada. To support public health and epidemiological activities, Foodbook was launched in 2014 by the Public Health Agency of Canada to collect representative information on food, water, and animal exposures, food safety knowledge, burden of gastrointestinal illnesses, and sociodemographic information. The aim of this overview was to identify how this valuable data source has been used in the past decade since its launch.

Methods: Peer-reviewed and grey literature were identified by applying the search term "Foodbook" to two academic databases and two grey literature sources, respectively. Citations were screened against eligibility criteria. Study information, including study characteristics, module of Foodbook data used, and how Foodbook data was used was extracted and synthesized in tabular format.

Results: A total of 27 articles were identified in the published literature that utilized Foodbook survey data in their analyses. The most common use was for outbreak investigations. In addition, Foodbook has been used to describe food, water, and animal exposures, determine food safety knowledge and practices of Canadians, estimate the burden of acute gastrointestinal illness, and evaluate data collection methods for foodborne illnesses.

Conclusion: By summarizing its use, the authors aim to encourage broader use of this publicly available data source to inform health protection and promotion activities to reduce the burden of enteric illnesses in Canada.

Background: Canada's Sexually Transmitted and Blood-borne Infections (STBBI) Action Plan and the Global Health Sector Strategies on STBBI highlight the importance of putting people at the centre of the health system response. Several key populations are disproportionately affected by viral hepatitis, including immigrants. However, there is a limited body of evidence on the burden of viral hepatitis among immigrants in Canada. We seek to address this gap by estimating the prevalence of hepatitis B (HBV) and C (HCV) infections among immigrants in Canada.

Methods: Using country- and region-specific publicly available data on the prevalence of HBV and HCV, we estimated the number of immigrants with chronic HBV (CHB), HCV antibodies, and chronic HCV (CHC) by multiplying the number of immigrants from Statistics Canada's 2021 census of population data by the corresponding publicly available country or region-of-origin prevalence, including lower and upper bounds. Each country was categorized as low (<2%) or intermediate-to-high (≥2%) based on published prevalence. To capture changes over time, estimates were stratified by time-period, where possible.

Results: In 2021, the estimated prevalence of viral hepatitis among all immigrants was 4.03% for CHB, 1.43% for HCV antibodies, and 0.78% for CHC. The estimated prevalence of CHB, HCV antibodies, and CHC was 0.91%, 0.96% and 0.52%, respectively, among immigrants from low-prevalence countries (<2%). It was 5.57%, 4.04%, and 2.20%, respectively, among immigrants from intermediate-to-high-prevalence countries (≥2%).

Conclusion: This is the first study to estimate the burden of HBV and HCV among immigrants at the national level in Canada. The results show that the prevalence of viral hepatitis among immigrants is higher than the general Canadian population. However, grouping all immigrants into one category masks important variation, and potentially over-estimates the burden of HBV and HCV among immigrants. Strengthening our understanding of hepatitis prevalence among immigrants can improve our ability to connect those in need to care and treatment services.

Background: Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are major causes of morbidity and mortality worldwide. Measuring the epidemiological burden of HCV and HBV in Canada is essential to measure progress towards global elimination targets and to ultimately eliminate viral hepatitis as a public health concern.

Objective: This study aimed to provide the first national estimates of HBV prevalence and unawareness, and to update estimates of HCV incidence, prevalence, and unawareness in the general population and key populations in Canada for 2021. Progress towards elimination targets for 2025, namely incidence, awareness, mortality, and HBV vaccination, was also assessed.

Methods: A combination workbook method and mathematical modelling was used to estimate the prevalence and unawareness of chronic hepatitis B (CHB), prevalence and incidence of anti-HCV antibodies, and the prevalence and unawareness of chronic hepatitis C (CHC).

Results: The estimated prevalence of CHB was 0.68% (plausible range: 0.40%-0.97%) or 262,000 (152,000-371,000) people in the general population, of whom 42.5% (33.9%-51.0%) were unaware of their infection. Immigrants from countries where HBV is common had the highest prevalence at 4.2% (1.9%-5.6%). An estimated 8,212 new HCV infections occurred in 2021, and the estimated prevalence of CHC was 0.56% (0.15%-0.97%) or 214,000 (58,500-369,000) people, of whom 41.5% (34.3%-48.8%) were unaware of their infection. People who inject drugs had the highest prevalence and largest proportion who were unaware at 36.9% (12.6%-55.1%) and 49.9% (29.0%-70.2%), respectively.

Conclusion: While the overall viral hepatitis burden is low in the general Canadian population, these estimates indicate that certain populations and communities remain disproportionately affected. Although Canada has met some of the 2025 targets, more work is needed. To this end, efforts to obtain and standardize provincial and national data will be required to measure progress towards all elimination targets.

Background: Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are sexually transmitted and blood-borne infections that Canada is committed to eliminate as public health concerns. Accurate epidemiological estimates require cross-sectional data as input. The objective of this study was to estimate the prevalence of present HBV infection (hepatitis B surface antigen-positive) and proportion aware of their infection, the vaccine-induced HBV immunity, the prevalence of HCV antibodies (anti-HCV-positive), the prevalence of present HCV infection (RNA-positive) and proportion aware of their infection, in the household population in Canada. These outcomes were also examined by selected demographic characteristics.

Methods: A total of 7,543 sera from participants of the Canadian Health Measure Survey (CHMS) cycles 5 (2016-2017) and 6 (2018-2019) who consented to participate in Statistics Canada's Biobank were tested to determine their HBV and HCV status. Information from the CHMS household questionnaire was linked to the laboratory results to report on sociodemographic characteristics and awareness of infection.

Results: The stored serum combined response rate for this study, which takes into account households' and respondents' participation in the CHMS and the Biobank was 42.8%. The estimated prevalence of present HBV infection among people aged 14 to 79 years was 0.4% (95% CI: 0.1%-0.7%), of whom 49.0% (95% CI: 15.4%-82.6%) were aware of their infection. An estimated 39.0% (95% CI: 37.0%-41.0%) of people aged 11 to 79 years had laboratory evidence of vaccine-induced HBV immunity. An estimated 0.5% (95% CI: 0.2%-0.8%) of people aged 14 to 79 years were positive for anti-HCV, and 0.2% (95% CI: 0.0%-0.3%) had a present infection (RNA-positive), of whom 51.2% (95% CI: 9.5%-92.9%) were aware of their infection.

Conclusion: Cross-sectional data using nationally representative surveys are essential in assessing the burden of viral hepatitis.

Background: Healthcare-associated infections (HAIs) are a significant healthcare burden in Canada. National surveillance of HAIs at sentinel acute care hospitals is conducted by the Canadian Nosocomial Infection Surveillance Program.

Objective: This article describes device and surgical procedure-related HAI epidemiology in Canada from 2019 to 2023.

Methods: Data were collected from 68 Canadian sentinel acute care hospitals between January 1, 2019, and December 31, 2023, for intensive care unit central line-associated bloodstream infections (ICU-CLABSIs), hip and knee surgical site infections (SSIs), cerebrospinal fluid (CSF) shunt SSIs and paediatric cardiac SSIs. Case counts, rates, patient and hospital characteristics, pathogen distributions and antimicrobial resistance data are presented.

Results: Between 2019 and 2023, 2,582 device-related infections and 1,029 surgical procedure-related infections were reported. Rates of ICU-CLABSIs fluctuated throughout the study period, with an overall increase in all intensive care unit settings except for the neonatal intensive care unit, where a 4% decrease was noted. An increase in SSIs following knee arthroplasty was observed, rising from 0.34 to 0.43 infections per 100 surgeries. Fluctuating trends were also observed in CSF shunt SSIs and paediatric cardiac SSIs over the study period. The most commonly identified pathogens were coagulase-negative staphylococci (23%) in ICU-CLABSIs and Staphylococcus aureus (42%) in SSIs.

Conclusion: Epidemiological and microbiological trends among selected device and surgical procedure-related HAIs are essential for benchmarking infection rates nationally and internationally, identifying any changes in infection rates or antimicrobial resistance patterns and helping inform hospital infection prevention and control and antimicrobial stewardship policies and programs.

Background: Healthcare-associated infections (HAIs) and antimicrobial resistance (AMR) continue to contribute to excess morbidity and mortality among Canadians.

Objective: This report describes epidemiologic and laboratory characteristics and trends of HAIs and AMR, 2019-2023, using surveillance and laboratory data submitted by hospitals to the Canadian Nosocomial Infection Surveillance Program (CNISP) and by provincial and territorial laboratories to the National Microbiology Laboratory.

Methods: Data was collected from 109 Canadian sentinel acute care hospitals between January 1, 2019 and December 31, 2023, for Clostridioides difficile infections (CDI), methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections (BSIs), vancomycin-resistant Enterococcus (VRE) BSIs (specifically Enterococcus faecalis and Enterococcus faecium), carbapenemase-producing Enterobacterales (CPE) and carbapenemase-producing Acinetobacter baumannii (CPA) infections and colonizations and Candida auris (C. auris). Trend analysis for case counts, incidence rates (rates), outcomes, molecular characterization and AMR profiles are presented.

Results: Rates remained relatively stable for CDI (range: 4.90-5.35 infections per 10,000 patient days) and MRSA BSI (range: 1.00-1.16 infections per 10,000 patient days) and increased significantly for VRE BSIs (range: 0.30-0.37 infections per 10,000 patient days). Infection rates for CPE remained low compared to other HAIs but doubled non-significantly (rates: 0.08-0.16), CPA counts remained very low (n=4 cases) and C. auris isolates remained low (n=36 isolates).

Conclusion: The incidence of MRSA BSIs and CDI remained stable and VRE BSIs and CPE infections increased in the Canadian acute care hospitals participating in CNISP. Few C. auris isolates were identified. Reporting standardized surveillance data to inform the application of infection prevention and control practices in acute care hospitals is critical to help decrease the burden of HAIs and AMR in Canada.

Background: The National HIV Surveillance Program, managed by the Public Health Agency of Canada, is a passive surveillance system that collects de-identified data on HIV cases in Canada. Regular review of this surveillance system is required to maintain its accuracy, effectiveness and relevance in the face of a changing HIV epidemic. The National HIV Surveillance Program is undergoing a comprehensive review and renewal process with the aim of identifying and implementing potential improvements to meet the information needs of communities, service providers, researchers, provinces and territories and the federal government more effectively.

Methods: A non-systematic literature review was conducted in June to July 2023, with 3,521 articles found and 105 included.

Objective: This literature review aimed to identify proposed approaches for public health surveillance, with an emphasis on HIV surveillance and identify key findings relating to the following themes: surveillance system infrastructure, data collection, ethical considerations and stakeholder relationships.

Results: Key findings from the literature review pertained to standardization and centralization of data collection; collection of demographics, disease staging, social determinants of health and other data elements; and linking surveillance systems to other data sources or other surveillance systems. Additional findings concerned legislative and policy review, privacy strategies, informed consent, ethical surveillance system design, stakeholder consultation at all stages, knowledge translation and ensuring adequate resourcing.

Conclusion: In future work, lessons resulting from the literature review will be combined with evidence from other components of the overall review of Canada's HIV surveillance system. Together, this information will be further assessed and prioritized for possible implementation after consultation with data providers and communities.

Background: Millions of Canadians contract enteric illnesses each year, many of which are acquired during, or are otherwise associated with, international travel. As the number of Canadians travelling fluctuates throughout the year, a corresponding change in the number of travel-acquired enteric illnesses was expected. A change in the number of travel-acquired enteric illnesses was also expected during the COVID-19 pandemic restrictions.

Objective: This study aims to explore trends in the number and distribution of select travel-acquired enteric infections in Canada, from May 2017 to April 2023.

Methods: To evaluate trends, Student's t-tests and negative binomial regression modelling were conducted. Percent changes and relative risks were calculated to assess the impact of the pandemic on travel-acquired enteric illnesses.

Results: Findings demonstrated a seasonal peak in the number of reported travel-acquired enteric illnesses during the winter and spring pre- and post-pandemic travel restrictions (May 2017-February 2020 and September 2021-April 2023). Additionally, there was a decrease in the number of travel-acquired enteric illnesses added to enteric illness travel clusters with cases in more than one province or territory (multi-jurisdictional) during and after the lifting of COVID-19 travel restrictions. However, cases reported post-travel restrictions had a higher risk of being added to a multi-jurisdictional enteric illness travel cluster compared to the pre-travel restriction phase.

Conclusion: Nonessential travel restrictions and changes in the healthcare-seeking behaviours due to the pandemic likely account in part for the change in the number of travel-acquired enteric illnesses observed while travel restrictions were implemented and after they were lifted. Further research is required to explain the increased risk of illnesses being added to multi-jurisdictional enteric illness travel clusters after the lifting of travel restrictions compared to pre-COVID-19.

A group of four healthy Canadian travellers visited a cenote in the Yucatán peninsula in April 2024 and subsequently developed symptomatic histoplasmosis. Diagnosis was made in the acute period with a positive urine Histoplasma antigen test in three of the cases. Two developed severe presentations and were treated with itraconazole, including a three-year-old child with disseminated disease. The sensitivity of different modalities for diagnostics depends on the timing and severity of illness, with Histoplasma urine antigen being most sensitive in early infection, serology converting 4-8 weeks following exposure and cultures generally of low sensitivity. Treatment depends on the disease manifestations and host immunologic status. Many patients have relatively mild, self-limited, influenza-like illness and the diagnosis may be overlooked. Given the number of Canadian tourists travelling to the Yucatán peninsula and the popularity of visiting cenotes, awareness of the risk of histoplasmosis associated with this exposure should be promoted.