Canadian SARS-CoV-2 serological survey using antenatal serum samples: a retrospective seroprevalence study.

BACKGROUND: Insufficient data on the rate and distribution of SARS-CoV-2 infection in Canada has presented a substantial challenge to the public health response to the COVID-19 pandemic. Our objective was to assess SARS-CoV-2 seroprevalence in a representative sample of pregnant people throughout Canada, across multiple time points over 2 years of the pandemic, to describe the seroprevalence and show the ability of this process to provide prevalence estimates. METHODS: This Canadian retrospective serological surveillance study used existing serological prenatal samples across 10 provinces over multiple time periods: Feb. 3-21, 2020; Aug. 24-Sept. 11, 2020; Nov. 16-Dec. 4, 2020; Nov. 15-Dec. 3, 2021; and results from the province of British Columbia during a period in which the SARS-CoV-2 B.1.1.529 (Omicron) variant was predominant, from Nov. 15, 2021, to June 11, 2022. Age and postal code administrative data allowed for comparison with concurrent polymerase chain reactivity (PCR)-positive results collected by Statistics Canada and the Canadian Surveillance of COVID-19 in Pregnancy (CANCOVID-Preg) project. RESULTS: Seropositivity in antenatal serum as early as February 2020 indicates SARS-CoV-2 transmission before the World Health Organization's declaration of the pandemic. Seroprevalence in our sample of pregnant people was 1.84 to 8.90 times higher than the recorded concurrent PCR-positive prevalence recorded among females aged 20-49 years in November-December 2020. Overall seropositivity in our sample of pregnant people was low at the end of 2020, increasing to 15% in 1 province by the end of 2021. Seroprevalence among pregnant people in BC during the Omicron period increased from 5.8% to 43% from November 2021 to June 2022. INTERPRETATION: These results indicate widespread vulnerability to SARS-CoV-2 infection before vaccine availability in Canada. During the time periods sampled, public health tracking systems were under-reporting infections, and seroprevalence results during the Omicron period indicate extensive community spread of SARS-CoV-2 infection.

Association of SARS-CoV-2 Infection During Pregnancy With Maternal and Perinatal Outcomes.

Importance: There are limited high-quality, population-level data about the effect of SARS-CoV-2 infection on pregnancy using contemporaneous comparator cohorts. Objectives: To describe maternal and perinatal outcomes associated with SARS-CoV-2 infection in pregnancy and to assess variables associated with severe disease in the pregnant population. Design, Setting, and Participants: CANCOVID-Preg is an observational surveillance program for SARS-CoV-2-affected pregnancies in Canada. This analysis presents exploratory, population-level data from 6 Canadian provinces for the period of March 1, 2020, to October 31, 2021. A total of 6012 pregnant persons with a positive SARS-CoV-2 polymerase chain reaction test result at any time in pregnancy (primarily due to symptomatic presentation) were included and compared with 2 contemporaneous groups including age-matched female individuals with SARS-CoV-2 and unaffected pregnant persons from the pandemic time period. Exposure: SARS-CoV-2 infection during pregnancy. Incident infections in pregnancy were reported to CANCOVID-Preg by participating provinces/territories. Main Outcomes and Measures: Maternal and perinatal outcomes associated with SARS-CoV-2 infection as well as risk factors for severe disease (ie, disease requiring hospitalization, admission to an intensive care unit/critical care unit, and/or oxygen therapy). Results: Among 6012 pregnant individuals with SARS-CoV-2 in Canada (median age, 31 [IQR, 28-35] years), the greatest proportion of cases were diagnosed at 28 to 37 weeks' gestation (35.7%). Non-White individuals were disproportionately represented. Being pregnant was associated with a significantly increased risk of SARS-CoV-2-related hospitalization compared with SARS-CoV-2 cases among all women aged 20 to 49 years in the general population of Canada (7.75% vs 2.93%; relative risk, 2.65 [95% CI, 2.41-2.88]) as well as an increased risk of intensive care unit/critical care unit admission (2.01% vs 0.37%; relative risk, 5.46 [95% CI, 4.50-6.53]). Increasing age, preexisting hypertension, and greater gestational age at diagnosis were significantly associated with worse maternal outcomes. The risk of preterm birth was significantly elevated among SARS-CoV-2-affected pregnancies (11.05% vs 6.76%; relative risk, 1.63 [95% CI, 1.52-1.76]), even in cases of milder disease not requiring hospitalization, compared with unaffected pregnancies during the same time period. Conclusions and Relevance: In this exploratory surveillance study conducted in Canada from March 2020 to October 2021, SARS-CoV-2 infection during pregnancy was significantly associated with increased risk of adverse maternal outcomes and preterm birth.

Feasibility of establishing a Canadian Obstetric Survey System (CanOSS) for severe maternal morbidity: a study protocol.

INTRODUCTION: Severe maternal morbidity (SMM)-an unexpected pregnancy-associated maternal outcome resulting in severe illness, prolonged hospitalisation or long-term disability-is recognised by many, as the preferred indicator of the quality of maternity care, especially in high-income countries. Obtaining comprehensive details on events and circumstances leading to SMM, obtained through maternity units, could complement data from large epidemiological studies and enable targeted interventions to improve maternal health. The aim of this study is to assess the feasibility of gathering such data from maternity units across Canadian provinces and territories, with the goal of establishing a national obstetric survey system for SMM in Canada. METHODS AND ANALYSIS: We propose a sequential explanatory mixed-methods study. We will first distribute a cross-sectional survey to leads of all maternity units across Canada to gather information on (1) Whether the unit has a system for reviewing SMM and the nature and format of this system, (2) Willingness to share anonymised data on SMM by direct entry using a web-based platform and (3) Respondents' perception on the definition and leading causes of SMM at a local level. This will be followed by semistructured interviews with respondent groups defined a priori, to identify barriers and facilitators for data sharing. We will perform an integrated analysis to determine feasibility outcomes, a narrative description of barriers and facilitators for data-sharing and resource implications for data acquisition on an annual basis, and variations in top-5 causes of SMM. ETHICS AND DISSEMINATION: The study has been approved by the Mount Sinai and Hamilton Integrated Research Ethics Boards. The study findings will be presented at annual scientific meetings of the Society of Obstetricians and Gynaecologists of Canada, North American Society of Obstetric Medicine, and International Network of Obstetric Survey Systems and published in an open-access peer-reviewed Obstetrics and Gynaecology or General Internal Medicine journal.

Pregnancy Outcomes During the COVID-19 Pandemic in Canada, March to August 2020.

OBJECTIVE: Several studies have documented changes in the rates preterm birth and stillbirth during the COVID-19 pandemic. We carried out a study to examine obstetric intervention, preterm birth, and stillbirth rates in Canada from March to August 2020. METHODS: The study included all singleton hospital deliveries in Canada (excluding Québec) from March to August 2020 (and March to August for the years 2015-2019) with information obtained from the Canadian Institute for Health Information. Data for Ontario were examined separately because this province had the highest rates of COVID-19 in the study population. Rates and odds ratios with 95% confidence intervals (CIs) were used to quantify pregnancy-related outcomes. RESULTS: There were 136,445 and 717,905 singleton hospital deliveries in Canada (excluding Quebéc) in from March to August 2020 and between March and August 2015-2019, respectively. Rates of obstetric intervention declined in early gestation in 2020. Odds ratios for labour induction and cesarean delivery at <32 weeks gestation for March-August 2020 versus March-August in 2015 to 2019 were 0.84 (95% CI 0.74-0.95) and 0.92 (95% CI 0.85-1.00), respectively. Preterm birth rates increased in Canada (excluding Québec) from 6.42% in March-August 2015 to 6.74% in March-August 2019 but were unchanged in March-August 2020 (6.74%). Stillbirth rates were stable between March-August 2015 and March-August 2020. However, stillbirth rates peaked in Ontario in April 2020 due to higher rates of stillbirths at 20-27 and 37-41 weeks gestation. CONCLUSION: Changes in labour induction and cesarean delivery at early gestation and other perinatal outcomes during the period of March to August 2020 highlight the need to reconsider the use and impact of obstetric services in pandemics as well as the need for timely perinatal surveillance.

Going with the Flow: Shifting Face-to-Face PD to Fully Online in the Era of COVID-19

Immersive professional development is often used to provide teachers first-hand experience in developing place-based curricula. Knowing this, we had carefully crafted such a professional development for our participants to learn how to engage their students in local watershed research and ecology. However, following year one of a two-year grant-funded weeklong summer professional development opportunity for teachers in the Okefenokee Swamp, a shift to online instruction occurred due to COVID-19 related travel restrictions. Although the first summer in the swamp and the successive year of follow-up with teacher participants proved successful, the shift to online asynchronous instruction proved surprisingly successful as well. Qualitative and quantitative data compared across year one and year two indicated positive outcomes, such as a self-paced, engaging experience that required outdoor activities in participants' local area.