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

Background: In Canada, HIV transmission continues to disproportionately affect the same communities of gay men, bisexual men and men who have sex with men (gbMSM); members of African, Caribbean or Black communities (ACB); people who use injection drugs; Indigenous people; and women who belong to the aforementioned groups. While primary care is an ideal location for HIV testing for members of these groups, many people do not have access to such healthcare services. In response, we launched GetaKit to distribute HIV self-tests.

Methods: In light of reduced access to healthcare services as a result of the pandemic and in anticipation of Health Canada's approval of an HIV self-test, a clinician-scientist research team at the University of Ottawa developed GetaKit: an online platform to provide access to sexual health services. When GetaKit first launched in Ottawa in July 2020 with funding from the Ontario Ministry of Health, its objectives were to ensure that access to the newly approved device remained 1) clinically appropriate, 2) accessible and 3) linked to care.

Results: Over the course of the study, there were a stable number of individuals who reported having never been tested for HIV before. These individuals tended to be younger and more likely to be members of racialized minority groups; similar characteristics to those who also face the most barriers to primary care access.

Conclusion: With new reports indicating that nearly six million Canadians are without a primary care provider, it was proposed that the popularity of the HIV self-test may tell more about this lack of access than about the utility of the device itself. While projects like GetaKit should be part of the broader strategy to overcome historic testing barriers, such as geographic distance and inconvenient clinic hours, it is important that this occurs in an environment where a strong primary care health system can support treatment, follow-up and specialist referrals, as required.

Background: Mycobacterial culture is routinely performed to diagnose tuberculosis (TB) in Canada. Globally, meta-analyses suggest that up to 2% of positive cultures are falsely positive for Mycobacterium tuberculosis due to laboratory cross-contamination. Five patients from distinct clinical institutions in Montréal were diagnosed with culture-positive TB as their clinical samples were processed in a centralized mycobacteria laboratory. Cross-contamination was suspected due to culture positivity in an organ donor with low TB pre-test probability. We describe a TB pseudo-outbreak due to laboratory cross-contamination and assess the role of conventional typing (i.e., mycobacterial interspersed repetitive unit variable number of tandem repeats [MIRU-VNTR]) and whole-genome sequencing (WGS) in supporting the investigation.

Methods: Patients' epidemiological risk factors and clinical presentations were reviewed. The trajectories of pre- and per-analytic samples were retraced to identify potential cross-contamination events. Tuberculosis isolates were characterized by MIRU-VNTR and WGS using Oxford Nanopore Technology (ONT). The bioinformatic pipeline tbpore (v0.7.1) cluster was used for phylogenetic analyses.

Results: Two patients had previous exposure to endemic settings and clinical symptoms compatible with TB. Culture media inoculation overlapped in time for four patients, including one with suspected pulmonary cavitary disease and an organ donor whose organs had been transplanted in three different receivers. The MIRU-VNTR and WGS typing confirmed isolates from those four patients to be identical.

Conclusion: Clinical, laboratory and molecular typing data, including results from ONT sequencing, were considered sufficiently robust to confirm laboratory cross-contamination and TB therapy was discontinued including in all organ transplant recipients.

Background: Without vaccination, approximately 75% of people in Canada will acquire a human papillomavirus (HPV) infection in their lifetime. HPV vaccine coverage rates continue to fall short of the national goal of 90% coverage for two or more doses by 17 years of age. Recent evidence and World Health Organization (WHO) guidance now support a 1- or 2-dose schedule for younger age groups, which can simplify vaccination efforts and improve coverage rates compared to a multi-dose immunization program.

Methods: The National Advisory Committee on Immunization (NACI) reviewed available evidence on the clinical benefits and risks of a 1-dose HPV vaccine schedule, as well as additional factors, including ethics, equity, feasibility and acceptability. The evidence and programmatic considerations were organized using a process informed by the Grading of Recommendations Assessment, Development and Evaluations (GRADE) framework and all of the information was used to facilitate NACI guidance development.

Results: A 1-dose schedule is highly effective against HPV infection based on available evidence in younger female populations, with current follow-up of up to 11 years following vaccination. Infectious disease modelling shows that a 1-dose strategy in males and females in Canada is expected to have similar health outcomes over the short and long term compared to two doses.

Conclusion: NACI updated recommendations for individuals 9 to 20 years of age to receive one dose of 9vHPV (Gardasil-9, Merck) vaccine. For individuals 21 years of age and older, a 2-dose schedule should be administered. Individuals considered immunocompromised and individuals infected with HIV should receive a 3-dose series. NACI also issued a discretionary recommendation for HPV vaccination for individuals 27 years and older, and updated guidance to allow HPV vaccine during pregnancy.

Background: In Canada, HIV transmission continues to disproportionately affect the same communities of gay men, bisexual men and men who have sex with men (gbMSM); members of African, Caribbean or Black communities (ACB); people who use injection drugs; Indigenous people; and women who belong to the aforementioned groups. While primary care is an ideal location for HIV testing for members of these groups, many people do not have access to such healthcare services. In response, we launched GetaKit to distribute HIV self-tests.

Methods: In light of reduced access to healthcare services as a result of the pandemic and in anticipation of Health Canada's approval of an HIV self-test, a clinician-scientist research team at the University of Ottawa developed GetaKit: an online platform to provide access to sexual health services. When GetaKit first launched in Ottawa in July 2020 with funding from the Ontario Ministry of Health, its objectives were to ensure that access to the newly approved device remained 1) clinically appropriate, 2) accessible and 3) linked to care.

Results: Over the course of the study, there were a stable number of individuals who reported having never been tested for HIV before. These individuals tended to be younger and more likely to be members of racialized minority groups; similar characteristics to those who also face the most barriers to primary care access.

Conclusion: With new reports indicating that nearly six million Canadians are without a primary care provider, it was proposed that the popularity of the HIV self-test may tell more about this lack of access than about the utility of the device itself. While projects like GetaKit should be part of the broader strategy to overcome historic testing barriers, such as geographic distance and inconvenient clinic hours, it is important that this occurs in an environment where a strong primary care health system can support treatment, follow-up and specialist referrals, as required.

Blastomycosis is a disease of potentially varied presentations caused by thermally dimorphic fungi that appear as mold at ambient temperatures and transform to yeast at body temperature. Inhalation of aerosolized fungal spores represents the primary mode of transmission. Exposure may follow outdoor activities that disturb soil, which is warm, moist, acidic and rich in organic debris, particularly within forested areas and in proximity to waterways. Blastomycosis is endemic to several parts of Canada, but is only reportable in Ontario and Manitoba, with Northwestern Ontario being considered a hyperendemic area with average annual incidence rates of over 25 cases per 100,000 population. Delays in diagnosis and treatment are frequently observed as the symptoms and imaging findings of blastomycosis may initially be mistaken for community-acquired pneumonia, tuberculosis or malignancy, which can result in interim disease progression and worsening clinical outcomes. Risks from fungal infections such as blastomycosis are likely to increase with climate change-associated shifts in temperature and rainfall, and this may contribute to the geographic expansion of cases, a phenomenon that appears to be already underway. Further research investigating the ecological niche of Blastomyces and its climate sensitivity could help facilitate better modelling of the potential impacts of climate change on risks to Canadians and inform more effective methods of exposure prevention. Early clinical recognition and treatment of blastomycosis remain the key to minimizing morbidity and mortality.

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 Vaccine for 2024-2025 updates the NACI recommendations from the previous year.

Objective: To summarize the 2024-2025 NACI seasonal influenza vaccine recommendations and to highlight new and updated information.

Methods: For the development of the Statement on Seasonal Influenza Vaccine for 2024-2025, the NACI Influenza Working Group applied the NACI evidence-based process to assess available evidence and formulate recommendations. These recommendations underwent a thorough evaluation and were approved by NACI based on the available evidence.

Results: Key updates for the 2024-2025 influenza season include updated immunization recommendations reflecting changes in influenza epidemiology and revised guidance for vaccine administration during pregnancy and in older adults.

Conclusion: The National Advisory Committee on Immunization recommends that any age-appropriate quadrivalent or trivalent influenza vaccine should be used for individuals six months of age and older who do not have contraindications or precautions. NACI reaffirms the importance of influenza vaccination with inactivated or recombinant influenza vaccines in pregnancy. Finally, NACI recommends that inactivated high-dose (IIV-HD), inactivated adjuvanted (IIV-Adj) or recombinant influenza vaccine (RIV) should be offered, when available, over other influenza vaccines for adults 65 years of age and older.

Background: Adults 65 years of age and older are at higher risk of influenza complications, such as hospitalization and death. As a result, seasonal influenza immunization is particularly important for this group.

Objective: This supplemental statement provides an evidence summary on the preferential use of one or more of the age-appropriate influenza vaccines for adults 65 years of age and older, over other age-appropriate influenza vaccines.

Methods: The National Advisory Committee on Immunization (NACI)'s Influenza Working Group undertook an overview of existing systematic reviews on the efficacy, effectiveness, safety and cost effectiveness of influenza vaccination in adults 65 years of age and older. Additionally, NACI's evidence-based process was used to assess the quality of eligible studies, summarize and analyze the findings and apply an ethics, feasibility and acceptability lens to develop recommendations.

Results: The evidence suggests that high-dose inactivated influenza vaccine (IIV-HD), adjuvanted inactivated influenza vaccine (IIV-Adj) and recombinant influenza vaccine (RIV) offer increased benefits for adults 65 years of age and older when compared to standard dose influenza vaccines. The IIV-HD had the most supporting evidence, followed by IIV-Adj and then RIV. Evidence comparing these enhanced vaccines was limited.

Conclusion: Following a thorough review of the complete body of evidence, NACI recommends that IIV-HD, IIV-Adj or RIV should be offered over other influenza vaccines for adults 65 years of age and older. NACI also continues to strongly recommend the inclusion of adults 65 years of age and older among those for whom it is particularly important to receive influenza vaccination.

The 2023-2024 influenza epidemic saw the return of typical late-season influenza B circulation. The epidemic was declared in week 45 (week ending November 11, 2023) due to the predominant circulation of influenza A(H1N1) and peaked in week 52 (week ending December 30, 2023); however, as influenza A circulation decreased, influenza B detections and the percentage of tests positive increased, reaching its peak in week 14 (week ending April 6, 2024). Influenza B/Victoria dominated this wave of activity, contributing to the ongoing discussion about the apparent disappearance of influenza B/Yamagata. With the recommendation for the removal of influenza B/Yamagata lineages from the recommended seasonal influenza vaccine components, the influenza surveillance community is preparing for the possibility of a new seasonal pattern dominated by influenza B/Victoria circulation. This season, as a result of influenza B/Victoria's overwhelming predominance, younger age groups were primarily affected by the wave of influenza B activity. Over the course of the season, among all influenza B detections, 52% occurred in children aged 0-19 years. Among all influenza B-associated hospitalizations, 46.4% were in children aged 0-19 years, and the highest cumulative hospitalization rates for influenza B were among children younger than five years (n=37 per 100,000 population) and children between the ages of 5-19 years (n=15 per 100,000 population). Continued vigilance and surveillance around influenza B trends and epidemiology is required to contribute to effective epidemic preparedness.

Background: In Canada, Salmonella enterica serovar Typhi infections are uncommon and typically travel-related. In November 2021, Ottawa Public Health identified a link between two typhoid fever cases, with no recent history of international travel, to the same grocery store ready-to-eat counter.

Objective: This report describes the outbreak response to a rare occurrence of chronic S. Typhi carriage in Ottawa, Ontario, Canada and provides recommendations for investigations of small-scale protracted outbreaks.

Methods: We administered exposure questionnaires using a single interviewer approach, tested stool samples of contacts and food handlers, inspected food premises, collected food samples and reviewed takeout receipts. Social network, spatial and whole genome sequencing analyses were used to investigate additional possible links between cases.

Results: Seven people with typhoid fever and onset from October 2018 to May 2022 were linked to an asymptomatic chronic S. Typhi carrier. Whole-genome sequencing confirmed that all eight isolates matched the outbreak cluster. All cases and carrier resided within an eight km radius in Ottawa. The chronic carrier worked as a food handler at various locations of a grocery store chain, including the implicated ready-to-eat counter. Transmission occurred via food handling, shared workspaces and social and household networks.

Conclusion: The chronic carrier was excluded from food handling until successful completion of treatment and clearance testing. We overcame the challenges of a small but prolonged outbreak by identifying an asymptomatic carrier using a multi-method approach including whole genome sequencing and social network analysis.

Background: During a public health emergency, it is vital to have access to data sources that can identify communities disproportionately affected and to ensure public health communications are meeting the needs of diverse populations.

Objective: To explore how administrative billing data for language interpretation services could be used as an additional source of information to understand the language profile of high-risk close contacts of COVID-19 cases.

Methods: A retrospective descriptive analysis was conducted using administrative billing data from Public Health Ontario's Contact Tracing Initiative from May 2020 to February 2022. Data from the Contact Tracing Initiative were utilized to identify drivers that could have influenced patterns in language interpretation requests. Trends were compared with community language profiles using 2021 Canadian Census data.

Results: Interpreters responded to 2,604 requests across 38,518 interpretation minutes and provided information in 50 different languages. The top five requested languages were French, Arabic, Spanish, Punjabi and Mandarin. Five distinct periods were identified of different language predominance including Spanish in spring/summer 2020, French in summer/fall 2020 and Arabic in spring 2021. Overall, these trends aligned with the language profile of health units contributing most submissions.

Conclusion: Public health agencies could benefit from using existing secondary data sources to understand the language interpretation needs of their communities. This study also demonstrated how existing data sources could be used to help assess how communities are being disproportionately affected by public health emergencies and how this might change over time.