OBJECTIVES: RSV is a major cause of LRTI among infants and is associated with substantial health and economic burden in Canada. RSVpreF, a maternal bivalent vaccine for the prevention of RSV-LRTI among infants, is currently under review by Health Canada. We assessed the potential public health impact of a year-round maternal vaccination program with RSVpreF for the prevention of RSV-LRTI among Canadian infants.

METHODS: A cohort model was used to evaluate the clinical outcomes and economic costs of RSV-LRTI among Canadian infants (N=369,092) during their first year of life, lifetime consequences of premature death due to RSV-LRTI, and impact of maternal vaccination (vs. no intervention). Clinical outcomes, including medically attended RSV-LRTI (stratified by care setting) and RSV-LRTI deaths, were projected monthly based on infant age, gestational age in weeks (wGA) at birth, RSV-LRTI disease/fatality rates, and mother’s vaccination status. Effectiveness of RSVpreF was based on clinical trial data and assumed to vary by care setting, time between vaccine administration and birth, and wGA at birth. Direct (i.e., medical care) and indirect (i.e., morbidity/mortality-related work loss) costs were calculated based on cases and corresponding unit costs, and were discounted at 1.5%/year.

RESULTS: Without vaccination, 6,002 hospitalizations, 14,172 emergency department (ED) visits, and 39,127 outpatient clinic (OC) encounters due to RSV-LRTI were projected to occur, resulting in direct costs of $68.6 million and indirect costs of $60.4 million. Assuming uptake consistent with maternal use of pertussis vaccine (64.8%), RSVpreF was projected to reduce RSV-LRTI hospitalizations by 2,002, ED visits by 3,056, and OC encounters by 8,536, yielding reductions in direct costs totaling $21.5 million and indirect costs totaling $15.5 million.

CONCLUSIONS: The results of this analysis suggest that a maternal vaccination program with RSVpreF in Canada would substantially reduce the clinical and economic burden associated with RSV-LRTI among infants.