Safety and Efficacy of Preventative COVID Vaccines- STOPCoV ( Phase 2)

There has been rapid approval of the COVID-19 vaccines. The participants in the initial research were mostly Caucasian with an average age of 50 years and with little underlying illness. More information is needed as to how well the vaccines work and are tolerated in older persons and in a more diverse population like Ontario. STOPCov has enrolled 911 persons over 70 years of age and is comparing them to 380 persons 30-50 years who received COVID vaccine. Participants completed an e-consent and were assigned a unique participant number to maintain confidentiality. They were emailed study documents and completed on-line questionnaires about their demographics, underlying illness and prescription medications and any prior COVID-19 diagnosis. They completed a 7 day on-line diary about any local (pain, swelling, redness) or systemic reactions (fever, chills, muscle aches) after each COVID-19 vaccine dose. More information is also needed on how well older individuals respond to the vaccine. In STOPCoV this is being determined by measuring the levels of antibodies or proteins produced in response to the vaccine. To do this part of the study, consenting participants collect their own blood spots from finger pricks with a lancet, apply the blood spots to a filter paper and mail them to the research center for analysis. Written and video instructions on how to do this were provided. It is becoming clear, that older ( and later younger) individuals will be offered a "booster" or third dose of vaccine. Hence this new phase of the study is proposed to determine the antibody response to a third vaccine dose, to follow the antibody levels for an additional year and to complete and additional 7-day diary about any side effects to the third dose. We will also study the impact of race, gender, and underlying illness (such as diabetes, high blood pressure, heart, liver or kidney disease) on vaccine safety and effectiveness. Our results will be shared with public health officials.