Targeting vaccination programs for respiratory syncytial virus (RSV) to older adults with underlying health conditions is a cost-effective way to reduce disease, according to a new modelling study in CMAJ (Canadian Medical Association Journal).

RSV infections cause major illness, especially in infants and older adults, and rates of infection increase with age. There are now vaccines available to prevent disease caused by RSV in adults, and vaccination campaigns may reduce the incidence in older adults and associated health care costs.

To understand the potential impact of RSV vaccinations, researchers created a model to assess the cost-effectiveness of vaccine programs in different age groups with different medical risk. Most existing cost-effectiveness studies have focused on adults aged 60 and older, but in this study, researchers focused on adults aged 50 and older. They analyzed a combination of age-only, medical risk–only and age- plus medical risk–based vaccination strategies. 

“Strategies focused on adults with underlying medical conditions that place them at increased risk of RSV disease are more likely to be cost-effective than general age-based strategies,” writes Dr. Ashleigh Tuite, the Centre for Immunization Programs at the Public Health Agency of Canada and the Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, with coauthors. “We found that vaccination of older adults may be less costly and more effective than no vaccination and that vaccinating people aged 70 years and older with chronic medical conditions is likely to be cost-effective based on commonly used cost-effectiveness thresholds.”

The research team notes that in some settings with higher risk of disease and higher health care costs, such as remote communities in Canada’s north, broader vaccination programs across age groups may be cost-effective.