COVID-19 vaccines are crucial for achieving sufficient immunisation coverage to manage the pandemic, but vaccine hesitancy persists. This study aimed to investigate the prevalence and determinants of vaccine hesitancy in adults and in parents for vaccinating their children using an integrated social cognition model. A community-based cohort in Singapore [N = 1623] completed a survey (wave 25) between June and July 2021 which measured their risk perceptions, distress, trust, vaccination beliefs, and vaccine intentions/behaviours. Results indicated low rates of hesitancy (9.9%) for own vaccination, with most concerns citing side effects, safety, and hasty development. Remaining respondents were vaccinated (69%) or intended to vaccinate (21%). The multivariable model (non-vaccinated respondents) indicated that, living with people in poor health, subjective norm, moral norm, benefits, and necessity of vaccination were associated with lower vaccine hesitancy (R2 Cox & Snell: 51.4%; p < 0.001). Hesitancy rates were higher for children's vaccination (15.9%), with male gender, lower perceived vaccine benefits, high COVID-19 risk perceptions, vaccination concerns, and necessity beliefs associated with higher odds of parental vaccine hesitancy (R2 Cox & Snell = 36.4%; p < 0.001). While levels of vaccine acceptance are high, more targeted messages are needed. For adults' vaccination, more emphasis should be on benefits and social gains, while for parental hesitancy, messages related to safety should be prioritised.
Keywords: COVID-19; parental hesitancy; psychosocial factors; sociodemographic factors; vaccine hesitancy.