A publicly-funded rotavirus (RV) immunization program designed to prevent hospitalizations and emergency department (ED) visits for RV-specific acute gastroenteritis (AGE) has shown remarkable improvements in direct and indirect effects 1.5 years after implementation, according to the results of a study published in the PLoS ONE.

“On August 8, 2011, Ontario became one of the first Canadian provinces to implement a universal, publicly-funded RV immunization program, using Rotarix vaccine at 2 and 4 months of age,” noted Dr. Sarah E. Wilson of Public Health Ontario in Toronto and the University of Toronto, and her colleagues. The program was subsequently implemented across 10 of 13 Canadian provinces and territories.

Dr. Wilson and colleagues conducted a retrospective longitudinal population-based cohort study examining health care utilization for AGE between the period of Aug. 1, 2005, and March 31, 2013, as identified from individual-level hospitalizations and ED visits present in the Discharge Abstract Database of the Canadian Institutes for Health Information and the National Ambulatory Care Reporting System, respectively. Furthermore, the study was divided into preprogram (Aug. 1, 2005-July 31, 2011) and a public program (Aug. 1, 2011-March 31, 2013) time periods (PLoS ONE 2016 May 11. doi: 10.1371/journal.pone.0154340 ).

Study results revealed that infants younger than 1 year of age showed the greatest reduction in the rate of RV-AGE hospitalizations after adjustment for secular trends and seasonality during the public program period (79%, rate ratio 0.21). Children 12-23 months of age (RR 0.27), 24-35 months of age (RR 0.48), 3-4 years of age (RR 0.31), and 5-19 years of age (RR 0.25) also showed significant reductions in RV-AGE hospitalizations. Significant decreases indicative of direct and indirect effects of immunization after adjustment for age, secular trends, and seasonality during the public program period also were demonstrated by a 68% reduction in RV-AGE ED visits (RR 0.32) and a 10% reduction in overall AGE ED visits (RR 0.90).

Regarding the greater implications of their study results, Dr. Wilson and colleagues suggested that their findings should help inform vaccine decision makers in regions without publicly funded RV programs as part of their routine immunization schedules.

Public Health Ontario and the Ontario Ministry of Health and Long-Term Care funded the study. The authors reported no conflicts of interest.