Public Health Agency of Canada

HIV pre-exposure prophylaxis (PrEP) is proven effective for HIV prevention and recommended for individuals at ongoing and high risk of HIV, including gay, bisexual, and other men who have sex with men (GBMSM) and people who inject drugs (PWID). We used existing national survey data to measure PrEP need in both populations and calculate percentages of use among those meeting indications within each group. We conducted a secondary data analysis of nationally representative data to estimate the percentage of GBMSM and PWID meeting PrEP indications based on 2017 Canadian guidelines. We applied these percentages to recent population size estimates for both groups to estimate the number of people having PrEP indications in each group. Where available, we also used survey data to determine the percentage of people with indications who were not taking PrEP at the time of the survey. An estimated 24.1% (95% CI 13.3-39.7%) or 99,300 (95% CI 54,800-163,600) of GBMSM had PrEP indications in Canada as of 2021. The corresponding percentage and number for PWID were 22.3% (20.8-22.8%) and 22,400 (20,900-23,900). Two-thirds of GBMSM participants (Sex Now 2019 and 2021) who had PrEP indications were not taking PrEP at the time of the surveys. None of the participants with PrEP indication in the Tracks survey (2017-2019) among PWID reported PrEP use. In Canada, the estimated number of people with PrEP indications among GBMSM and PWID far exceeded documented levels of use. Uptake of PrEP was lower among PWID compared to GBMSM. Efforts to improve PrEP access and uptake could help reduce HIV transmission in Canada.

The Canadian Sentinel Practitioner Surveillance Network used the test-negative design to assess KP.2 vaccine effectiveness (VE) against medically attended outpatient COVID-19 between November 2024 and April 2025 among participants ≥ 12 years. Analyses included 5410 controls (19% vaccinated) and 435 COVID-19 cases (10% vaccinated). Nearly three-quarters (72%) of contributing case viruses were genetically characterized, with XEC (35%) and KP.3.1.1 (38%) variants most commonly identified. Vaccination reduced COVID-19 risk by approximately half (54%; 95% CI: 36-68) relative to unvaccinated individuals. VE was greatest during the first 2 months postvaccination, reducing risk by two-thirds and declining to minimal protection by the fifth month postvaccination.

Introduction L’environnement bâti favorise l’activité physique en offrant des possibilités d’être actif dans sa vie quotidienne. Les expériences naturelles sont précieuses pour évaluer la manière dont les modifications à l’environnement bâti dans le monde réel affectent l’activité physique et sont essentielles pour guider les politiques visant à améliorer l’activité physique à l’échelle de la population. Cette étude visait à synthétiser les données probantes issues d’expériences naturelles ayant porté sur les répercussions des modifications à l’environnement bâti sur l’activité physique au Canada. Méthodologie Des recherches ont été effectuées dans MEDLINE, Embase, PsycINFO, ProQuest Public Health et SportDISCUS, de la création au 27 novembre 2024. Toutes les évaluations d’expériences naturelles incluant un groupe de comparaison ou un point de référence dans le passé et évaluant les changements dans l’activité physique associés à des modifications à l’environnement bâti étaient admissibles. Une synthèse narrative résume les données probantes, en présentant leur degré de certitude. Résultats Les résultats des 25 expériences naturelles sélectionnées révèlent des effets positifs, avec un degré de certitude faible à modéré, de l’augmentation du potentiel piétonnier, des nouvelles infrastructures cyclables et piétonnes, des programmes de vélos en libre-service (location de vélos) et des nouveaux sentiers. On observe en revanche avec un degré de certitude de très faible à faible une absence d’effets notables pour le service rapide par bus, l’amélioration des bâtiments scolaires et des cours de récréation et l’aménagement des zones scolaires. Certaines données probantes suggèrent que les parcs canins où les chiens peuvent circuler sans laisse ont des effets négatifs sur l’activité physique des enfants dans les parcs, et que les améliorations apportées aux cours de garderies ont des effets sur l’activité physique d’intensité modérée à vigoureuse. Conclusion Peu d’études canadiennes ont évalué les répercussions des modifications à l’environnement bâti sur l’activité physique, la plupart d’entre elles ayant été publiées dans la dernière décennie. Les études futures devraient inclure des échantillons plus importants et plus diversifiés ainsi que toutes les régions, contrôler pour les facteurs de confusion, notamment les variations saisonnières de l’activité physique en plein air, utiliser des groupes témoins bien appariés et intégrer des mesures objectives de l’activité physique.

Background: Uncertainty is inherent in public health emergency management (PHEM) due to the unpredictable nature of emergencies and interplay of public health threats and their drivers. PHEM practitioners must continually develop and adapt methods to manage this uncertainty. General morphological analysis (GMA) is a computer-aided scenario modelling method that effectively addresses issues where uncertainty exists. GMA examines possible components of a complex problem and allows practitioners to consider potential connections and outcomes. Through iterative steps, GMA can generate new knowledge and insights in the development of scenarios to aid in decision-making and planning within PHEM. Method: An environmental scan was designed to identify articles that utilized GMA as one of the primary methodologies across different natural hazards within the context of PHEM. Academic databases included PubMed and Research Gate. A broad search strategy was applied to scan grey literature which included Google Scholar. Results: This environmental scan identified ten examples of GMA employed in PHEM across multiple countries and organizations. Examples in the literature targeted either a specific natural hazard or broadly targeted all known natural hazards. The findings can be divided into three interconnected categories: (a) scenario modelling for managing natural disasters, (b) strategy development and prioritization tools, and (c) decision-making support tools for emergency management teams. Conclusions: GMA is a decision-making and planning tool in PHEM that can be extended beyond scenario modelling to address uncertainties. This modelling method leverages subject matter experts to uncover innovative connections and outcomes when navigating complex problems like those observed within PHEM. Future research can involve applying GMA to PHEM in a Canadian context. Currently, the Public Health Agency of Canada is applying GMA to cyclical events (e.g., wildfires, floods, extreme heat events, and extreme weather events) to create scenarios using a PHEM lens. Future practice should involve integrating GMA with other PHEM methodologies to enhance strategies to prevent, prepare, respond and recover from future public health emergencies.

Coping strategies are essential for psychological well-being and healthy survivorship experience of patients with breast cancer. However, there is a research gap in the understanding of coping strategies and their associated factors among patients with breast cancer in Nigeria. This study aimed to investigate coping strategies, focusing on disengagement coping and its relationship with sociodemographic and illness-related factors in a sample of patients with breast cancer in South-South, Nigeria. A cross-sectional study was conducted among 240 breast cancer patients at a tertiary hospital in the South‒South region of Nigeria. The participants completed a clinico-sociodemographic questionnaire to gather their background information and the 32-item Coping Strategies Inventory (CSI-32) to assess coping. The mean age of the participants was 46.8 years (SD = 13.4), and most participants were employed (89.2%), married (62.1%), and had children (74.6%). Most participants (n = 179, 74.6%) presented with advanced breast cancers (stage 3 and 4) and reported poor treatment adherence (n = 185, 77.1%). The findings on CSI-32 revealed a significantly greater reliance on disengagement coping (61.25%, n = 147) strategies (e.g., wishful thinking and social withdrawal) compared with engagement coping (38.75%, n = 93). Disengagement coping was significantly associated with those with fewer children, χ2(1, N = 240) = 4.93, p = .03; post-primary education level, χ2(1, N = 240) = 5.71, p = .01; being employed, χ²(1, N = 240) = 6.38, p = .01; early cancer stage, χ2(1, N = 240) = 2.94, p = .03; and poor treatment adherence, χ2(1, N = 240) = 3.22, p = .03. Following regression analysis, individuals with disengagement coping were more likely to be employed, have post-primary education, and report poor treatment adherence. There is a need for psychosocial interventions to bolster healthy coping strategies amongst patients with breast cancer in this region, preferably by reducing a reliance on disengagement coping and ultimately improving psychological well-being. Such interventions need to be holistic and tailored to the unique attributes of individual patient using a patient-centered care model. Our study findings also highlight the need for future research with robust methodology, especially prospective studies, to better understand the trajectory of coping strategies in patients with breast cancer and the impacts on their wellbeing.

Antimicrobial use (AMU) in finfish aquaculture production raises concerns about the link between AMU and the development of antimicrobial resistance (AMR) in bacteria found in aquatic organisms and potential transmission to humans and the environment. The objective of this study was to describe the antimicrobial susceptibilities of a historical collection of bacterial isolates from diagnostic submissions from farmed finfish in British Columbia (BC), Canada. Antimicrobial susceptibility data were obtained from the BC Ministry of Agriculture via submissions to the Animal Health Centre for 2007 to 2018 for florfenicol (FLOR), oxytetracycline (OXY), trimethoprim-sulfadiazine (SXT), and triple-sulfa compound (TRI). There were 1237 unique isolates from all finfish species (68 unique bacterial species), of which 1042 were from Atlantic salmon. For all fish species, the most common bacterial species isolated were Aeromonas salmonicida (n = 174), Aliivibrio wodanis (n = 84), and Yersinia ruckeri (n = 79). Resistance was detected to most antimicrobials tested, but levels were generally low. Resistance to FLOR was only detected in A. salmonicida. Low annual isolate numbers precluded genera-specific annual comparisons for all pathogens. Multi-drug resistance was detected, but at low levels. These results provide an important baseline for antimicrobial susceptibility data from bacterial isolates that may cause disease in finfish aquaculture in BC, Canada that will support future Canadian AMR surveillance in farmed aquaculture.

This corrigendum is being published to add a clarification on page 361 of the following article: Gariépy G, Prowse RKM, Plouffe R, Graham E. Supervised consumption sites and population-level overdose mortality: a systematic review of recent evidence, 2016-2024. Health Promot Chronic Dis Prev Can. 2025;45(9):357-66. https://doi.org/10.24095/hpcdp.45.9.02 Text has been added to highlight an important precision about the Rammohan et al. study. Bold has been used to identify the added text. The authors thank Dr. Daniel Werb for raising this concern.

Background Mpox-related ophthalmic disease (MPOXROD) ranges from mild conjunctivitis to sight-threatening keratitis, however, data based on systematic ophthalmological assessment are scarce. We aimed to characterise the prevalence, features, and temporal evolution of MPOXROD during a clade Ib mpox outbreak. Methods We conducted MBOTE-EYE, a prospective ophthalmological sub-study, nested within a clinical characterisation cohort in Kamituga, South-Kivu, Democratic Republic of the Congo. All hospitalised patients with mpox confirmed by PCR in the prior 48 hours were eligible. Participants underwent comprehensive ophthalmological examination at enrolment, discharge, and days 29 and 59 post-diagnosis. Conjunctival swabs were collected for monkeypox virus PCR testing. MPOXROD was defined as conjunctivitis, scleritis, keratitis, uveitis, or optic nerve involvement. Risk factors were assessed using mixed-effects Poisson regression. Findings Between 28 October 2024 and 30 June 2025, 310 participants were enrolled (median age 14 years, IQR 2.5-25.0; 53.5% female, n=166/310). At enrolment, conjunctivitis was present in 36.1% (95% CI 31.0-41.6%, n=112/310), keratitis in 7.7% (95% CI 5.3-11.3%), and anterior uveitis in 0.6% (95% CI 0.2-2.3%). Overall, 43.2% (95% CI 37.8-48.8%) developed MPOXROD during follow-up, most often bilaterally. Visual acuity <8/10 occurred in 22.9% (95% CI 17.6-29.2%, n=24/310), and persistent blindness in 0.9% (95% CI 0.24-5.5%, n=2/225), due to ulcerative keratitis. Periorbital lesions (adjusted risk ratio [aRR] 2.82, 95% CI 1.40-5.69) and severe malnutrition (aRR 5.06, 2.25-11.38) were independently associated with MPOXROD. Conjunctival swabs with PCR Ct values < 25 occurred exclusively in participants with active MPOXROD. Interpretation Ophthalmic involvement in clade Ib mpox is common and frequently bilateral, with a substantial burden of keratitis and risk of vision loss, particularly in young children and severely malnourished individuals. These findings highlight the need for systematic eye examinations in mpox care and provide critical evidence to inform future trials of targeted ophthalmic therapies.