In Ontario, rotavirus vaccination yields benefits

Last Updated: 2016-05-16

By Will Boggs MD

NEW YORK (Reuters Health) - Ontario's universal rotavirus vaccination of infants has reduced acute gastroenteritis rates among infants and other groups not vaccinated, researchers report.

"The most interesting finding is that we saw a reduction in overall acute gastroenteritis (AGE) hospitalizations across the lifespan, including adults over the age of 65, where hospitalizations were reduced by 20% since the launch of the rotavirus program, even after adjusting for secular trends," Dr. Sarah Wilson from Public Health Ontario and University of Toronto, Ontario, Canada, told Reuters Health by email. "This is exciting because it demonstrates the extent of herd effects from the vaccine program."

Prior to rotavirus vaccine introduction, rotavirus was responsible for up to 40% of all childhood AGE and was associated with more health care resource utilization than other causes of AGE.

Ontario implemented universal vaccination of infants at 2 and 4 months of age in August 2011, with first-year coverage estimated at 80%.

Dr. Wilson's team used data from the Ontario Health Insurance Plan (OHIP) to evaluate the population level direct and indirect effects of this program on health services use, hospitalizations, and emergency department (ED) visits for AGE.

Age-specific rotavirus AGE rates and overall AGE hospitalizations and ED visits decreased in all age cohorts, with the exception of overall AGE ED visits for those aged 20 to 44 years, according to the May 11 PLoS ONE online report.

The average age-specific monthly rate of rotavirus AGE hospitalizations declined from 0.52 to 0.08 per 10,000 population among infants younger than 12 months.

Overall AGE hospitalizations declined by 20-38% across all age groups, including seniors aged 65 and older, and overall AGE ED visits among young children declined by 18-19%.

"The advice from the National Advisory Committee on Immunization (Canada's expert body on vaccine recommendations) is to give the first dose of rotavirus vaccine by 15 weeks of age and to complete the series by 8 months of age," Dr. Wilson explained. "Because of these age-based scheduling considerations, rotavirus vaccine programs are typically implemented without catch-up programs to reach older children."

"Anyone who has ever cared for a sick child with acute gastroenteritis knows how unpleasant this illness is, and how easily it can be spread to siblings, parents, and other caregivers," she concluded. "Our paper adds to an accumulating number of studies that demonstrate the effectiveness of the rotavirus vaccine and that with high uptake, reductions in hospitalizations for acute gastroenteritis can be dramatic, and with reductions in older children and adults too old to have been vaccinated themselves."

The authors reported no funding or disclosures.

SOURCE: http://bit.ly/22dGmPK

PLoS ONE 2016.