Integrating Longitudinal Epidemiologic, Virologic and Immunologic Analyses to Understand COVID-19 Immunity and Infection Outcomes in Long Term Care [ILEVIA, study data contributed to the CITF Databank]

<b>Background:</b> Vaccination programs are essential for protecting residents of long-term care (LTC) facilities, as they are more vulnerable to adverse outcomes from COVID-19. <br>

<b>Aims of the CITF-funded study:</b> The main goals of the ILEVIA study were to characterize immune responses to SARS-CoV-2 infection and vaccination. The study also aimed to identify correlates of vaccine immunity, assess vaccine willingness and hesitancy, and support investigations of COVID-19 if an outbreak occurred in the presence/absence of vaccination. <br>

<b>Methods:</b> This cohort study recruited residents and staff from LTC facilities and community members living in Vancouver, British Columbia. Participants provided a blood sample and questionnaire responses (or by proxy or chart review, as needed) at baseline, which was at or shortly before a first dose of SARS-CoV-2 vaccination for most participants. Follow-up visits occurred at 1 month after the first dose, 1 month, 3, and 6 months after second dose of the COVID-19 vaccine. Later, the study was extended to include additional follow-ups at 1 month, 3, and 6 months after the third dose of the COVID-19 vaccine. Participants provided a blood sample at every visit, and follow-up questionnaires were also administered at intervals. For immune response objectives, the team collaborated with the COVID-19 Vaccination among People Living with HIV: Immunogenicity, Effectiveness, and Safety [https://doi.org/10.5683/SP3/QVGXRL]<br>

<b>Contributed dataset contents:</b> The data sets include 152 participants (89 healthcare workers, 24 residents from long-term care facilities and 39 seniors living in the community) who completed baseline visits between December 2020 and Apr 2021. All participants gave one or more blood samples during baseline and follow-up visits. A total of 104 participants gave blood samples in all 8 follow-up visits (5 original and 3 extended follow-ups). A total of 1,108 blood samples were collected between Dec 2020 and Aug 2022. <br>

A demographic and health questionnaire were completed by or for participants at baseline and follow-up visit questionnaire data is available for about 80% of the participants. Variables include data in the following areas of information: demographics (age, sex and gender, ethnicity), general health (tobacco use, chronic conditions, weight and height, flu vaccine, access to primary care), exposure risk factors (occupation, travel, gathering, compliance with COVID prevention measures), longitudinal follow-up for COVID infections (COVID test, symptoms), COVID vaccination history and willingness, and laboratory measures of immune response (serology). <br>