"I Want People to Be Able to Make an Informed Choice": How Quebec naturopaths discuss vaccination in their practice.

Health care providers' recommendations can play an important role in individuals' vaccination decisions. Despite being one of the most popular complementary and alternative medicine (CAM), naturopathy is understudied in relation to vaccination decisions. We sought to address this gap through this study of vaccination perspectives of naturopathy practitioners in the province of Quebec, Canada. We conducted in-depth interviews with 30 naturopaths. Thematic analysis was conducted. Main themes were developed deductively (i.e., based on prior literature) and expanded through inductive coding of the data. Participants noted that they discuss vaccination in their practice, but only when clients asked questions or wanted advice. Naturopaths described refraining from explicitly recommending for or against vaccination. Instead, they focus on empowering their clients to make their own informed decision regarding vaccination. Most participants noted that they direct clients towards sources of information so that clients could decide for themselves, but some mentioned they discussed with clients what they considered to be risks associated with vaccination, as well as its benefits. These discussions were framed through a personalized and individual approach with clients.

Socioeconomic disparities and concentration of the spread of the COVID-19 pandemic in the province of Quebec, Canada.

BACKGROUND: Recent studies suggest that the risk of SARS-CoV-2 infection may be greater in more densely populated areas and in cities with a higher proportion of persons who are poor, immigrant, or essential workers. This study examines spatial inequalities in SARS-CoV-2 exposure in a health region of the province of Quebec in Canada. METHODS: The study was conducted on the 1206 Canadian census dissemination areas in the Capitale-Nationale region of the province of Quebec. The observation period was 21 months (March 2020 to November 2021). The number of cases reported daily in each dissemination area was identified from available administrative databases. The magnitude of inequalities was estimated using Gini and Foster-Greer-Thorbecke (FGT) indices. The association between transmission and socioeconomic deprivation was identified based on the concentration of transmission in socially disadvantaged areas and on nonparametric regressions relating the cumulative incidence rate by area to ecological indicators of spatial disadvantage. Quantification of the association between median family income and degree of exposure of dissemination areas was supplemented by an ordered probit multiple regression model. RESULTS: Spatial disparities were elevated (Gini = 0.265; 95% CI [0.251, 0.279]). The spread was more limited in the less densely populated areas of the Quebec City agglomeration and outlying municipalities. The mean cumulative incidence in the subsample made up of the areas most exposed to the pandemic was 0.093. The spread of the epidemic was concentrated in the most disadvantaged areas, especially in the densely populated areas. Socioeconomic inequality appeared early and increased with each successive pandemic wave. The models showed that areas with economically disadvantaged populations were three times more likely to be among the areas at highest risk for COVID-19 (RR = 3.55; 95% CI [2.02, 5.08]). In contrast, areas with a higher income population (fifth quintile) were two times less likely to be among the most exposed areas (RR = 0.52; 95% CI [0.32, 0.72]). CONCLUSION: As with the H1N1 pandemics of 1918 and 2009, the SARS-CoV-2 pandemic revealed social vulnerabilities. Further research is needed to explore the various manifestations of social inequality in relation to the pandemic.

[Les personnes âgées immigrantes et leurs proches à Montréal : des vies oubliées durant la pandémie].

Malgré l'attention renouvelée de plusieurs médias sur la question des risques liés à la COVID-19 au sein de diverses communautés marginalisées au Québec, nous entendons encore très peu parler des personnes âgées immigrantes et de leurs proches. Dans cette note sur les politiques et pratiques, nous aborderons l'expérience du contexte pandémique chez les personnes âgées immigrantes montréalaises et leurs réseaux. Nous présenterons d'abord quelques données sociodémographiques sur les immigrants âgés montréalais. Nous exposerons ensuite nos constats sur les impacts de la COVID-19 sur les personnes âgées immigrantes, en particulier en ce qui concerne l'accès aux soins de la santé et aux services sociaux, la proche-aidance, l'emploi et le logement, à partir de nos travaux et de la littérature en gérontologie sociale. Nous terminerons en proposant quelques recommandations qui permettraient d'améliorer l'inclusion sociale des personnes âgées immigrantes et de leurs proches, autant en matière de politiques publiques que de pratiques sur le terrain.

Determinants of work-family balance satisfaction during the pandemic: Insights from Québec.

The first wave of the COVID pandemic was the most challenging for employed parents, and more specifically for women. In Québec, research has shown a deterioration in the psychological health of parents in the early weeks of the pandemic. In this research, we investigate how Québec parents who remained employed during the lockdown in 2020 perceived their work-family balance in the stressful context of new earning and caregiving constraints, drawing on survey data collected in May 2020. Our approach integrates insights from psychological, managerial and sociological literatures. We find that most parents who remained employed found their work-family balance "easy" in the first months of the pandemic, but women felt less satisfied with their work-family balance than men as well as those whose employers were less understanding and supportive, and those whose workloads increased. The implications of these results are discussed in the light of previous studies on work-family intersections, to show that gender continues to matter when family members are faced with extraordinary circumstances such as the closing of childcare and schools, even in the egalitarian context of Québec, where fathers are perceived as legitimate caregivers.

La première vague de la pandémie de COVID a été la plus difficile pour les employés avec des enfants, et plus particulièrement pour les femmes. Au Québec, la recherche a révélé une détérioration de la santé psychologique des parents au Québec dans les premières semaines de la pandémie. Dans cette recherche, nous examinons la manière dont les parents québécois demeurés en emploi pendant le confinement en 2020 ont perçu leur conciliation emploi-famille dans le contexte stressant de nouvelles contraintes en matière de revenus et de prestation de soins, en nous appuyant sur les données d'enquête recueillies en mai 2020. Notre approche intègre des notions issues de la littérature en gestion, en psychologie et en sociologie. Nos résultats montrent que la plupart des parents qui ont conservé leur emploi ont perçu leur conciliation emploi-famille comme étant « facile ¼ au cours des premiers mois de la pandémie, mais que les femmes se sont senties moins satisfaites de leur conciliation emploi-famille que les hommes, ainsi que ceux dont les employeurs ont été moins compréhensifs et moins coopératifs, et ceux dont la charge de travail a augmenté. Les implications de ces résultats sont discutées à la lumière d'études antérieures sur les intersections emploi-famille, pour montrer que le genre continue d'avoir de l'importance lorsque les membres de la famille sont confrontés à des circonstances extraordinaires telles que la fermeture des services de garde et des écoles, même dans le contexte égalitaire du Québec, où les pères sont perçus comme des dispensateurs de soins légitimes.

Adapting Hospital Work During COVID-19 in Quebec (Canada).

Among hospital responses to the COVID19 pandemic worldwide, service reorganization and staff reassignment have been some of the most prominent ways of adapting hospital work to the expected influx of patients. In this article, we examine work reorganization induced by the pandemic by identifying the operational strategies implemented by two hospitals and their staff to contend with the crisis and then analyzing the implications of those strategies. We base our description and analysis on two hospital case studies in Quebec. We used a multiple case study approach, wherein each hospital is considered a unique case. In both cases, work adaptation through staff reassignment was one of the critical measures undertaken to ensure absorption of the influx of patients into the hospitals. Our results showed that this general strategy was designed and applied differently in the two cases. More specifically, the reassignment strategies revealed numerous healthcare resource disparities not only between health territories, but also between different types of facilities within those territories. Comparing the two hospitals' adaptation strategies showed that past reforms in Quebec determined what these reorganizations could achieve, as well as how they would affect workers and the meaning they gave to their work.

Early Impact of the COVID-19 Pandemic on Acute Stroke Treatment Delays.

This is an observational cohort study comparing 156 patients evaluated for acute stroke between March 30 and May 31, 2020 at a comprehensive stroke center with 138 patients evaluated during the corresponding time period in 2019. During the pandemic, the proportion of COVID-19 positive patients was low (3%), the time from symptom onset to hospital presentation was significantly longer, and a smaller proportion of patients underwent reperfusion therapy. Among patients directly evaluated at our institution, door-to-needle and door-to-recanalization metrics were significantly longer. Our findings support concerns that the current pandemic may have a negative impact on the management of acute stroke.

Cohort profile: A Québec-based plasma donor biobank to study COVID-19 immunity (PlasCoV).

PURPOSE: The long-term humoral immunity to COVID-19 is not well understood owing to the continuous emergence of new variants of concern, the evolving vaccine-induced and infection-induced immunity, and the limited duration of follow-up in previous studies. As the sole blood service in Québec (Canada), Héma-Québec established a COVID-19-focused biobank ('PlasCoV') in April 2021. PARTICIPANTS: As of January 2022, the biobank included 86 483 plasma samples from 15 502 regular donors (age range=18-84 years, females=49.7%), for an average of 5.6 donations per donor. Nearly two-thirds (65.6%) of biobank donors made at least two donations, with many donors having provided samples prevaccination and postvaccination (3061 (19.7%)) or preinfection and postinfection (131 (0.8%)), thus allowing for longitudinal studies on vaccine-induced and infection-induced immunity. FINDINGS TO DATE: A study that used PlasCoV samples revealed that previously infected individuals who received a single dose of the BNT162b2 COVID-19 vaccine exhibited the strongest immune response. By contrast, SARS-CoV-2-naïve individuals required two vaccine doses to produce a maximal immune response. Furthermore, the results of a four-phase seroprevalence study indicated that the antinucleocapsid (N) response wanes rapidly, so that up to one-third of previously infected donors were seronegative for anti-N. FUTURE PLANS: Donations from individuals who consented to participate before 1 October 2022 will be collected up until 31 March 2023. This plasma biobank will facilitate the conduct of longitudinal studies on COVID-19 immunity, thus helping to provide valuable insights into the anti-SARS-CoV-2 immune response and its persistence, and the effects of vaccination and variants on the specificity of the anti-SARS-CoV-2 immune response.

How Did an Integrated Health and Social Services Center in the Quebec Province Respond to the COVID-19 Pandemic? A Qualitative Case Study.

During the first and second waves of the pandemic, Quebec was among the Canadian provinces with the highest COVID-19 mortality rates. Facing particularly large COVID-19 outbreaks in its facilities, an integrated health and social services center in the province of Quebec (Canada), developed resilience strategies. To explore these diverse responses to the crisis, we conducted a case study analysis of a Quebec integrated health and social services center, building on a conceptualization of resilience strategies using "configurations" of effects, strategies, and impacts. Qualitative data from 14 indepth interviews conducted in the summer and fall of 2020 with managers and frontline practitioners were analyzed through the lens of situations of "anticipation," "reaction," or "inaction." The findings were discussed in three results dissemination workshops, two with practitioners and one with managers, to discern lessons they learned. Three major configurations emerged: 1) reorganization of services and spaces to accommodate more COVID-19 patients; 2) management of contamination risks for patients and professionals; and 3) management of personal protective equipment (PPE), supplies, and medications. Within these configurations, the responses to the crisis were strongly shaped by the 2015 health care system reforms in Quebec and were constrained by organizational challenges that included a centralized model of governance, a history of substantial budget cuts to longterm care facilities, and a systematic lack of human resources.

A comparative analysis of non-invasive prenatal testing in Ontario and Quebec: the role of governing style in health technology innovation & adoption.

BACKGROUND: While processes of adoption and the impacts of various health technologies have been extensively studied by health services and policy researchers, the influence of policy makers' governing styles on these processes have been largely neglected. Through a comparative analysis of non-invasive prenatal testing (NIPT) in the Canadian provinces of Ontario and Quebec, this article examines how decisions about this technology were shaped by contrasting political ideologies, resulting in vastly different innovation and adoption strategies and outcomes. METHODS: A comparative qualitative investigation comprising of a document analysis followed by semi-structured interviews with key informants. Interview participants were researchers, clinicians, and private sector medical laboratory employees based in Ontario and Quebec, Canada. Interviews were conducted both in person and virtually- owing partly to the COVID-19 pandemic - to garner perspectives regarding the adoption and innovation processes surrounding non-invasive prenatal testing in both provinces. All interviews were recorded and transcribed verbatim and data were analyzed using thematic analysis. RESULTS: Through an analysis of 21 in-depth interview transcripts and key documents, the research team identified three central themes: 1) health officials in each province demonstrated a unique approach to using the existing scholarly literature on NIPT; 2) each provincial government demonstrated its own preference for service delivery, with Ontario preferring private and Quebec preferring public; and finally, 3) both Ontario and Quebec's strategies to NIPT adoption and innovation was contextualized within each province's unique financial positioning and concerns. These findings illustrate how both Quebec's nationalist focus and use of industrial policy and Ontario's 'New Public Management' style had implications for how this emerging healthcare technology was made available within each province's publicly-financed health system. CONCLUSIONS: Our study reveals how these governments' differing approaches to using data and research, public versus private service delivery, and financial goals and concerns resulted in distinct testing technologies, access, and timelines for NIPT adoption. Our analysis demonstrates the need for health policy researchers, policy makers, and others to move beyond analyses solely considering clinical and health economic evidence to understand the impact of political ideologies and governing styles.

Explainable Machine Learning Model to Predict COVID-19 Severity Among Older Adults in the Province of Quebec.

Context: Patients over the age of 65 years are more likely to experience higher severity and mortality rates than other populations from COVID-19. Clinicians need assistance in supporting their decisions regarding the management of these patients. Artificial Intelligence (AI) can help with this regard. However, the lack of explainability-defined as "the ability to understand and evaluate the internal mechanism of the algorithm/computational process in human terms"-of AI is one of the major challenges to its application in health care. We know little about application of explainable AI (XAI) in health care. Objective: In this study, we aimed to evaluate the feasibility of the development of explainable machine learning models to predict COVID-19 severity among older adults. Design: Quantitative machine learning methods. Setting: Long-term care facilities within the province of Quebec. Participants: Patients 65 years and older presented to the hospitals who had a positive polymerase chain reaction test for COVID-19. Intervention: We used XAI-specific methods (e.g., EBM), machine learning methods (i.e., random forest, deep forest, and XGBoost), as well as explainable approaches such as LIME, SHAP, PIMP, and anchor with the mentioned machine learning methods. Outcome measures: Classification accuracy and area under the receiver operating characteristic curve (AUC). Results: The age distribution of the patients (n=986, 54.6% male) was 84.5□19.5 years. The best-performing models (and their performance) were as follows. Deep forest using XAI agnostic methods LIME (97.36% AUC, 91.65 ACC), Anchor (97.36% AUC, 91.65 ACC), and PIMP (96.93% AUC, 91.65 ACC). We found alignment with the identified reasoning of our models' predictions and clinical studies' findings-about the correlation of different variables such as diabetes and dementia, and the severity of COVID-19 in this population. Conclusions: The use of explainable machine learning models, to predict the severity of COVID-19 among older adults is feasible. We obtained a high-performance level as well as explainability in the prediction of COVID-19 severity in this population. Further studies are required to integrate these models into a decision support system to facilitate the management of diseases such as COVID-19 for (primary) health care providers and evaluate their usability among them.

"It felt like building a plane while in flight": the consideration of social inequalities in the design and planning of a contact-tracing intervention for COVID-19 in Montreal, Quebec.

OBJECTIVE: In Canada and globally, the COVID-19 pandemic has increased social inequalities in health (SIH), furthering the vulnerability of certain groups and communities. Contact-tracing is a cornerstone intervention with COVID-19 prevention and control programs. The aim of this study was to describe whether and how SIH were considered during the design of the COVID-19 contact-tracing intervention in Montreal. METHODS: This study is part of the multi-country research program HoSPiCOVID, looking at the resilience of public health systems during the COVID-19 pandemic. A descriptive qualitative study was carried out in Montreal, based on a "bricolage" conceptual framework describing the consideration for SIH in intervention and policy design. Qualitative data were collected using semi-structured interviews with 16 public health practitioners, recruited using both purposive and snowball sampling. Data were analyzed thematically, both inductively and deductively. RESULTS: According to participants, SIH were not initially considered during the design of the contract-tracing intervention in Montreal. The participants were frustrated by the Minister of Health's initial resistance to integrating SIH into their public health response. However, adaptations were gradually made to better meet the needs of underserved populations. CONCLUSION: There is a need for a clear and common vision of SIH within the public health system. Decision-makers need to consider SIH prior to designing public health interventions in order for these not to further increase SIH in the future, especially in the face of a health crisis.

RéSUMé: OBJECTIF: Au Canada et dans le monde, la pandémie de COVID-19 a augmenté les inégalités sociales de santé (ISS), aggravant la vulnérabilité de certains groupes et communautés. Le suivi des contacts est une intervention fondamentale des programmes de prévention et de contrôle de la COVID-19. L'objectif de cette étude était de décrire si et comment les ISS ont été prises en compte lors de la conception de l'intervention de suivi des contacts pour la COVID-19 à Montréal. MéTHODES: Cette étude fait partie du programme de recherche multi-pays HoSPiCOVID, portant sur la résilience des systèmes de santé publique pendant la pandémie de COVID-19. Une étude qualitative descriptive a été menée à Montréal, sur la base d'un cadre conceptuel « bricolage ¼ décrivant la prise en compte des ISS dans la conception des interventions et des politiques. Des données qualitatives ont été recueillies au moyen d'entrevues semi-structurés avec 16 praticiens de la santé publique, recrutés par échantillonnage raisonné et en boule de neige. Les données ont été analysées de manière thématique, de façon inductive et déductive. RéSULTATS: Selon les participants, les ISS n'ont pas été initialement prises en compte lors de la conception de l'intervention de suivi des contacts à Montréal. Les professionnels de santé publique ont déploré le manque de volonté du Ministère de la Santé d'intégrer les ISS dans la réponse de santé publique. Toutefois, des adaptations ont été progressivement apportées pour mieux répondre aux besoins des populations vulnérables. CONCLUSION: Il est nécessaire d'avoir une vision claire et commune des ISS au sein du système de santé. Les décideurs doivent prendre en compte activement les ISS pour que celles-ci soient mieux conceptualisées, et que les interventions de santé publique n'aggravent pas les ISS, surtout en période de crise sanitaire.

Suicide Attempts in Children Aged 10-14 Years During the First Year of the COVID-19 Pandemic.

PURPOSE: To determine if suicide attempts increased during the first year of the pandemic among young adolescents in Quebec, Canada. METHODS: We analyzed children aged 10-14 years who were hospitalized for a suicide attempt between January 2000 and March 2021. We calculated age-specific and sex-specific suicide attempt rates and the proportion of hospitalizations for suicide attempts before and during the pandemic and compared rates with patients aged 15-19 years. We used interrupted time series regression to measure changes in rates during the first (March 2020 to August 2020) and second (September 2020 to March 2021) waves and difference-in-difference analysis to determine if the pandemic had a greater impact on girls than boys. RESULTS: Suicide attempt rates decreased for children aged 10-14 years during the first wave. However, rates increased sharply during the second wave for girls, without changing for boys. Girls aged 10-14 years had an excess of 5.1 suicide attempts per 10,000 at the start of wave 2, with rates continuing to increase by 0.6 per 10,000 every month thereafter. Compared with the prepandemic period, the increase in the proportion of girls aged 10-14 years hospitalized for a suicide attempt was 2.2% greater than that of boys during wave 2. The pattern seen in girls aged 10-14 years was not present in girls aged 15-19 years. DISCUSSION: Hospitalizations for suicide attempts among girls aged 10-14 years increased considerably during the second wave of the pandemic, compared with boys and older girls. Young adolescent girls may benefit from screening and targeted interventions to address suicidal behavior.

The effect of the COVID-19 pandemic on pediatric asthma-related emergency department visits and hospital admissions in Montréal, Quebec: a retrospective cohort study.

BACKGROUND: Asthma is a chronic respiratory condition that affects 10% of Canadian children and is often exacerbated by viral respiratory infections, prompting concerns about the severity of SARS-CoV-2 disease in children with asthma. We compared sociodemographic and clinical characteristics of children presenting to the emergency department and the incidence of these visits, before and during the pandemic. METHODS: We included children aged 0 to 17 years presenting with asthma to 2 tertiary pediatric emergency departments in Montréal, Quebec, between the prepandemic (Jan. 1, 2017, to Mar. 31, 2020) and pandemic (Apr. 1, 2020, to June 30, 2021) periods. We compared the number of emergency department visits and hospital admissions with an interrupted time series analysis and compared the sociodemographic characteristics based on the Canadian Index of Multiple Deprivation (CIMD) and clinical characteristics (including triage level, intensive care admissions, etc.) with Mann-Whitney and χ2 tests. RESULTS: We examined 22 746 asthma-related emergency department visits. During the pandemic, a greater proportion of patients presented a triage level 1 or 2 (19.3% v. 14.7%) and were admitted to the intensive care unit (2.5% v. 1.3%). The patients' CIMD quintile distributions did not differ between the 2 periods. We found a 47% decrease (relative risk [RR] 0.53, 95% confidence interval [CI] 0.37 to 0.76) in emergency department visits and a 49% decrease (RR 0.51, 95% CI 0.34 to 0.76) in hospital admissions during the pandemic. INTERPRETATION: The decrease in asthma-related emergency department visits was observed through the third wave of the pandemic, but children presented with a higher acuity and with no identified sociodemographic changes. Future studies are required to understand individual behaviours that may have led to the increased acuity at presentation observed in this study.

Trajectories of psychological distress during the COVID-19 pandemic among community-dwelling older adults in Quebec: A longitudinal study.

OBJECTIVE: The COVID-19 pandemic and its associated public health measures may increase the risk for psychological distress among vulnerable older adults. This longitudinal study aimed to identify predictors of psychological distress trajectories among community-dwelling older adults in Quebec, Canada. METHODS: The study spanned four time points across 13 months and three waves of the COVID-19 pandemic. The sample included 645 community-dwelling older adults ages 60 years and older in Quebec. Participants completed telephone-based interviews that included the Kessler 6-item Psychological Distress Scale (K6) to assess psychological distress at each time point as well as information on socioeconomic, medical, psychological and COVID-19 related factors. Group-based trajectory modelling was used to identify distinct trajectories of psychological distress across time. RESULTS: Three group-based trajectories of psychological distress were identified: the resilient (50.5%), reactive (34.9%), and elevated distress groups (14.6%). Individuals with mobility issues, insomnia symptoms, COVID-19 related acute stress, general health anxiety, increased loneliness symptoms, and those unable to use technology to see others were more likely to be in the reactive and elevated groups than the resilient group. Those with past mental health problems had uniquely increased odds of being in the reactive group compared to the resilient group. Individuals living in poverty and those who reported taking psychotropic medication had increased odds of being in the elevated distress group compared to the resilient group. CONCLUSION: These findings characterized distinct trajectories of psychological distress in older adults and identified risk factors for elevated distress levels.

COVID-19: Physical Activity Behavior Change among Athletes in Québec (Canada).

The context of the COVID-19 pandemic imposed unprecedented restrictions. Within Canada, which is among the most stringent countries in terms of sanitary rules, Québec was among the provinces that imposed the strictest sanitary measures. The impacts of some measures were felt the most among athletes since they made it difficult, if not impossible, to practice their sports. This article therefore aimed to (1) evaluate the impact of the pandemic on the athletes' overall level of physical activity, (2) look at the relationship between overall level of physical activity and the level of psychological well-being and (3) analyze post-pandemic physical activity intentions. For this purpose, an online survey was conducted among 1456 athletes aged 3 to 61 years old. The results of this study show that the limitations imposed during the pandemic led to half of athletes decreasing their overall level of physical activity, leading to a deterioration in their psychological well-being (F(2.1438) = 54.707, p < 0.001). The current research provided further evidence that it is essential to implement strategies that favor practicing physical activities in a pandemic context. Furthermore, since almost all individuals who increased their practice of wheeled sports during the pandemic intend to continue after the pandemic, this is a great opportunity to promote active transportation among athletes by ensuring that the perception of the benefits associated with it does not decrease with time.

Estimation of COVID-19 Period Prevalence and the Undiagnosed Population in Canadian Provinces: Model-Based Analysis.

BACKGROUND: The development of a successful COVID-19 control strategy requires a thorough understanding of the trends in geographic and demographic distributions of disease burden. In terms of the estimation of the population prevalence, this includes the crucial process of unravelling the number of patients who remain undiagnosed. OBJECTIVE: This study estimates the period prevalence of COVID-19 between March 1, 2020, and November 30, 2020, and the proportion of the infected population that remained undiagnosed in the Canadian provinces of Quebec, Ontario, Alberta, and British Columbia. METHODS: A model-based mathematical framework based on a disease progression and transmission model was developed to estimate the historical prevalence of COVID-19 using provincial-level statistics reporting seroprevalence, diagnoses, and deaths resulting from COVID-19. The framework was applied to three different age cohorts (< 30; 30-69; and ≥70 years) in each of the provinces studied. RESULTS: The estimates of COVID-19 period prevalence between March 1, 2020, and November 30, 2020, were 4.73% (95% CI 4.42%-4.99%) for Quebec, 2.88% (95% CI 2.75%-3.02%) for Ontario, 3.27% (95% CI 2.72%-3.70%) for Alberta, and 2.95% (95% CI 2.77%-3.15%) for British Columbia. Among the cohorts considered in this study, the estimated total number of infections ranged from 2-fold the number of diagnoses (among Quebecers, aged ≥70 years: 26,476/53,549, 49.44%) to 6-fold the number of diagnoses (among British Columbians aged ≥70 years: 3108/18,147, 17.12%). CONCLUSIONS: Our estimates indicate that a high proportion of the population infected between March 1 and November 30, 2020, remained undiagnosed. Knowledge of COVID-19 period prevalence and the undiagnosed population can provide vital evidence that policy makers can consider when planning COVID-19 control interventions and vaccination programs.

Importance of occupation for SARS-CoV-2 seroprevalence and COVID-19 vaccination among correctional workers in Quebec, Canada: A cross-sectional study.

Background: Correctional workers are at increased risk of SARS-CoV-2 infection. We examined the seroprevalence of SARS-CoV-2, determined the effects of carceral and occupational exposures on seropositivity, and explored predictors of COVID-19 vaccine uptake among correctional workers in Quebec, Canada. Methods: We conducted a cross-sectional seroprevalence study in three provincial prisons. The primary and secondary outcomes were SARS-CoV-2 antibody seropositivity (Roche Elecsys® serology test) and self-reported COVID-19 vaccination status ("fully vaccinated" defined as two doses or prior infection plus one dose), respectively. Poisson regression models with robust standard error were used to examine the effect of occupational variables with SARS-CoV-2 seropositivity and predictors of COVID-19 vaccine uptake. Estimates are presented as crude and adjusted prevalence ratios (aPR) with 95% confidence intervals (95% CI). Results: From 14 July to 15 November 2021, 105/600 (18%) correctional workers tested positive across three prisons (range 11-21%); 76% were fully vaccinated. Seropositivity was affected by prison occupation (aPR 1.59, 95% CI 1.11-2.27 for correctional officers vs. all other occupations) and low perceived concern of SARS-CoV-2 acquisition (aPR 1.62, 95% CI 1.11-2.38 for not/hardly worried vs. somewhat/extremely worried). Predictors of being fully vaccinated included race/ethnicity (aPR 0.86, 95% CI 0.76-0.99 for visible minority vs. White), presence of comorbidities (aPR 1.14, 95% CI 1.02-1.28 for > 2 vs. none), and prison occupation (aPR 0.82, 95% CI 0.73-0.92 for correctional officers vs. all other occupations). Conclusions: Correctional officers were most likely to have acquired SARS-CoV-2, but least likely to be vaccinated, underscoring the importance of addressing both occupational risks and COVID-19 vaccine hesitancy to mitigate future outbreaks.

Measuring progress towards reaching zero new HIV acquisitions among key populations in Québec (Canada) using routine surveillance data: a mathematical modelling study.

INTRODUCTION: Men who have sex with men (MSM) and people who inject drugs (PWID) are disproportionately impacted by the HIV epidemic in Canada. Having the second-highest provincial diagnosis rate, an improved understanding of the epidemic among these populations in Québec could aid ongoing elimination efforts. We estimated HIV incidence and other epidemic indicators among MSM and PWID in Montréal and across Québec using a back-calculation model synthesizing surveillance data. METHODS: We developed a deterministic, compartmental mathematical model stratified by age, HIV status and disease progression, and clinical care stages. Using AIDS and HIV diagnoses data, including self-reported time since the last negative test and laboratory results of CD4 cell count at diagnosis, we estimated HIV incidence in each population over 1975-2020 by modelling a cubic M-spline. The prevalence, undiagnosed fraction, fraction diagnosed that started antiretroviral treatment (ART) and median time to diagnosis were also estimated. Since the COVID-19 pandemic disrupted testing, we excluded 2020 data and explored this in sensitivity analyses. RESULTS: HIV incidence in all populations peaked early in the epidemic. In 2020, an estimated 97 (95% CrI: 33-227) and 266 (95% CrI: 103-508) HIV acquisitions occurred among MSM in Montréal and Québec, respectively. Among PWID, we estimated 2 (95% CrI: 0-14) and 6 (95% CrI: 1-26) HIV acquisitions in those same regions. With 2020 data, unless testing rates were reduced by 50%, these estimates decreased, except among Québec PWID, whose increased. Among all, the median time to diagnosis shortened to <2 years before 2020 and the undiagnosed fraction decreased to <10%. This fraction was higher in younger MSM, with 22% of 15-24 year-olds living with HIV in Montréal (95% CrI: 9-39%) and 31% in Québec (95% CrI: 17-48%) undiagnosed by 2020 year-end. Finally, ART access neared 100% in all diagnosed populations. CONCLUSIONS: HIV incidence has drastically decreased in MSM and PWID across Québec, alongside significant improvements in diagnosis and treatment coverage-and the 2013 introduction of pre-exposure prophylaxis. Despite this, HIV transmission continued. Effective efforts to halt this transmission and rapidly diagnose people who acquired HIV, especially among younger MSM, are needed to achieve elimination. Further, as the impacts of the COVID-19 pandemic on HIV transmission are understood, increased efforts may be needed to overcome these.