Parental acceptability of new RSV preventive therapies for infants: A cross-sectional survey in Canada.

Two new RSV immunization products exist for infants: a prenatal vaccine (RSVpreF) and a long-acting monoclonal antibody for infants (nirsevimab). While both showed promise in clinical trials, implementation has varied across jurisdictions. Before rollout in Canada, we conducted an anonymized, online survey with a nationally representative sample of 1,015 expectant and recent birth parents. The primary outcome was product acceptability (disagree, undecided, agree). Odds ratios (ORs) and 95% confidence intervals (CIs) identified factors associated with agreement or indecision versus disagreement. Approximately 49% (n = 499) were expecting; 51% (n = 516) had a baby in the past year. Overall, 72% (n = 727) agreed to receive a product: 61% (n = 624) for RSVpreF and 60% (n = 608) for nirsevimab. RSVpreF agreement was higher among older parents (e.g., OR = 3.64; 95% CI, 1.99-6.67 for age 25-34 versus 18-24 years), those with a university degree (OR = 3.65; 95% CI, 2.01-6.64 versus high school), higher income (OR = 2.31; 95% CI, 1.01-5.28 for ≥$150k versus <$40k), or receipt/intention for Tdap (OR = 3.76; 95% CI, 2.37-5.96 versus no receipt/intention) or influenza (OR = 2.04; 95% CI, 1.29-3.21) vaccines. Agreement was higher among parents of children without a high-risk medical condition compared to those with (OR = 2.32; 95% CI, 1.44-3.72). Similar trends were observed for nirsevimab, with lower agreement also noted among those who self-researched antibodies (OR = 0.51; 95% CI, 0.30-0.88 versus not). As most respondents rated product safety (76%), effectiveness (71%), and disease severity risk (70%) as important in decision-making, providing clear information on these, alongside communications targeted to subgroups with lower agreement, may optimize uptake as programs rollout.