Seropositivity of SARS-CoV-2 in an unvaccinated cohort in British Columbia, Canada: a cross-sectional survey with dried blood spot samples.

OBJECTIVES: Gathering population-based data on prevalence of SARS-CoV-2 infection is vital to the public health response and planning. Current seroprevalence data in BC are limited with respect to considerations of how socioeconomic and demographic factors, such as age, sex, gender, income, identifying as a visibility minority and occupation, are related to SARS-CoV-2 antibody detection due to infection-acquired immunity. We aimed to estimate the SARS-CoV-2 seropositivity in a cohort of British Columbians, using at-home self-collected dried blood spot (DBS) samples. DESIGN: This cross-sectional study included online surveys that collected sociodemographic and COVID-19 vaccine receipt information, and an at-home DBS collection kit. SETTING: British Columbia (BC), Canada. PARTICIPANTS: Eligible participants were aged 25-69 years and residents of BC. PRIMARY OUTCOME MEASURE: SARS-CoV-2 anti-spike IgG antibody detection in unvaccinated individuals. Adjusted incidence rate ratios (aIRR) explored factors associated with seropositivity. RESULTS: SARS-CoV-2 serology was performed on a total of 4048 unvaccinated participants 25-69 years of age who submitted DBS samples taken from November 2020 to June 2021. A total of 118 seropositive cases were identified, for an estimated overall seropositivity of 2.92% (95% CI 2.42% to 3.48%). Participants identifying as a visible minority had a higher seropositivity, 5.1% vs 2.6% (p=0.003), compared with non-visible minority participants. After adjustment by age and sex, identifying as a visible minority (aIRR=1.85, 95% CI 1.20 to 2.84) remained the only significant factor associated with SARS-CoV-2 antibody detection in this cohort of unvaccinated individuals. CONCLUSIONS: SARS-CoV-2 seropositivity in the BC population due to infection-acquired immunity was low. Seropositivity indicated that among those unvaccinated, visible minority communities have been most impacted. Continued monitoring of SARS-CoV-2 serology due to both infection-acquired and vaccine-acquired immunity will be vital in public health planning and pandemic response.

Intention to Receive a COVID-19 Vaccine by HIV Status Among a Population-Based Sample of Women and Gender Diverse Individuals in British Columbia, Canada.

COVID-19 vaccination is recommended for people living with HIV (PLWH), among whom social inequities and co-morbidities may drive risks of COVID-19 infection and outcome severity. Among a provincial (British Columbia) sample, we determined the prevalence of COVID-19 vaccine intention by HIV status and assessed socio-demographic, vaccine hesitancy, and psychological predictors of vaccine intention. Individuals (25-69 years) recruited from province-wide research cohorts and the general public completed an online survey examining COVID-19 impacts (August/2020-March/2021). In an analysis restricted to women and gender diverse participants (n = 5588), we compared intention to receive a recommended COVID-19 vaccine (Very likely/Likely vs Neutral/Unlikely/Very Unlikely) by self-reported HIV status. Logistic regression models assessed the independent effect of HIV status and other factors on COVID-19 vaccine intention. Of 5588 participants, 69 (1.2%) were living with HIV, of whom 79.7% were on antiretroviral therapy. In bivariate analyses, intention to vaccinate was significantly lower among PLWH compared to participants not living with HIV (65.2% vs 79.6%; OR 0.44; 95%CI 0.32-0.60). However, this association was not statistically significant after adjustment for ethnicity, income, education, and essential worker status (aOR 0.85; 95%CI 0.48-1.55). Among PLWH, those with greater vaccine confidence, positive attitudes towards the COVID-19 vaccine, and more strongly influenced by direct and indirect social norms to vaccinate had significantly higher odds of vaccine intention. Tailored messaging is needed to build vaccine confidence, address questions about vaccine benefits, and support informed vaccination decision-making to promote COVID-19 vaccine uptake among women and gender diverse people living with HIV.

British Columbia CARMA-CHIWOS Collaboration (BCC3): protocol for a community-collaborative cohort study examining healthy ageing with and for women living with HIV.

INTRODUCTION: Women living with HIV (WLWH) experience accelerated ageing and an increased risk of age-associated diseases earlier in life, compared with women without HIV. This is likely due to a combination of viral factors, gender differences, hormonal imbalance and psychosocial and structural conditions. This interdisciplinary cohort study aims to understand how biological, clinical and sociostructural determinants of health interact to modulate healthy ageing in WLWH. METHODS AND ANALYSIS: The British Columbia Children and Women: AntiRetroviral therapy and Markers of Aging-Canadian HIV Women's Sexual and Reproductive Health Cohort Study (CARMA-CHIWOS) Collaboration (BCC3) study will enrol WLWH (n=350) and sociodemographically matched HIV-negative women (n=350) living in British Columbia. A subset of BCC3 participants will be past participants of CARMA, n≥1000 women and children living with and without HIV, 2008-2018 and/or CHIWOS, n=1422 WLWH, 2013-2018. Over two study visits, we will collect biological specimens for virus serologies, hormones and biological markers as well as administer a survey capturing demographic and sociostructural-behavioural factors. Sociodemographics, comorbidities, number and type of chronic/latent viral infections and hormonal irregularities will be compared between the two groups. Their association with biological markers and psychostructural and sociostructural factors will be investigated through multivariable regression and structural equation modelling. Retrospective longitudinal analyses will be conducted on data from past CARMA/CHIWOS participants. As BCC3 aims to follow participants as they age, this protocol will focus on the first study visits. ETHICS AND DISSEMINATION: This study has been approved by the University of British Columbia Children's and Women's Research Ethics Board (H19-00896). Results will be shared in peer-reviewed journals, conferences and at community events as well as at www.hivhearme.ca and @HIV_HEAR_me. WLWH are involved in study design, survey creation, participant recruitment, data collection and knowledge translation. A Community Advisory Board will advise the research team throughout the study.