Booster jabs strongly enhance Covid-19 immunity in care home residents and staff

elderly person receiving a Covid vaccination - A Covid-19 booster vaccination markedly increases immune response in residents and staff within care homes, according to a new preprint study co-led by UCL researchers, making it vital that people living and working in these settings get their third jab. Age and frailty are already recognised as major risk factors for severe Covid-19 outcomes, with elderly residents of long-term care facilities suffering much higher rates of mortality during the pandemic than the general population. Single or dual Covid-19 vaccination has provided strong clinical protection against severe disease within this group, but there has been concern about the potential impact of immunity waning and the need for vaccine boosters in those at greatest risk. Researchers studied immune responses in 134 staff and residents in 19 long-term care homes who had received an mRNA booster vaccine (Pfizer), following two doses of either the Pfizer or AstraZeneca vaccines. In a preprint article published on SSRN (yet to be peer-reviewed), they show that SARS-CoV-2-specific antibody responses were substantially increased in this vulnerable population after a third dose of vaccine - calculated from blood samples collected from 25 May to 18 November 2021. Median time of sample collection after booster shot was 28 days for this cohort. Previous research from the Vivaldi study team had shown that prior natural infection strongly enhanced subsequent Covid-19 vaccine responses, but that uninfected older people who had been vaccinated exhibited a weaker immune response.