This CITF-funded research, which is in pre-print, was led by Lunenfeld-Tanenbaum Research Institute (LTRI) senior scientists Dr. Anne-Claude Gingras and Dr. Allison McGeer and reveals that long-term care (LTC) residents in Ontario who received the Pfizer vaccine had lower antibody responses to Alpha, Beta and Gamma than those vaccinated with the Moderna vaccine. The Delta variant was not assessed.