While the introduction of free flu shots has significantly decreased the number of influenza cases in Ontario, a new University of Waterloo study suggests there is still room for improvement.

According to the study, which was recently published in the Journal of Health Communications, 34 per cent of Ontarians received the influenza vaccine in 2013-14.

Of those who did not, about half questioned either the necessity of getting the flu shot, the vaccine’s effectiveness at preventing illness, or both.

“Our research suggests that the majority of people who do not get the flu shot have concerns regarding vaccine effectiveness, or a believe that they have a strong immune system and won’t be affected by the flu,” Waterloo professor and study lead author Samantha Meyer said in a news release.

Ontario introduced its universal flu shot program in 2000. Since then, the province has seen an average of 61 per cent fewer flu cases annually, meaning savings of $7.8 million in health-care costs.

Other reasons given for not getting the flu shot include moral and religious objections, as well as unsatisfactory prior experiences with vaccines.