Impact of Universal Influenza Vaccination in Ontario

publication 10 minutes Evidence: high

Author Information

Author(s): Jeffrey C. Kwong, Thérèse A. Stukel, Jenny Lim, Allison J. McGeer, Ross E. G. Upshur, Helen Johansen, Christie Sambell, William W. Thompson, Deva Thiruchelvam, Fawziah Marra, Lawrence W. Svenson, Douglas G. Manuel

Primary Institution: Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada

Hypothesis

Does the introduction of a universal influenza immunization program reduce influenza-associated mortality and health care use compared to targeted vaccination programs in other provinces?

Conclusion

The introduction of universal vaccination in Ontario was associated with significant reductions in influenza-associated mortality and health care use compared to other provinces.

Supporting Evidence

Influenza-associated mortality decreased by 74% in Ontario after the introduction of the universal vaccination program.
Hospitalizations for influenza-associated conditions decreased more in Ontario than in other provinces.
Emergency department visits for influenza-related issues also saw a greater reduction in Ontario.

Takeaway

When everyone in Ontario got free flu shots, fewer people got sick and needed to go to the hospital compared to other places that only vaccinated certain groups.

Methodology

The study analyzed mortality and hospitalization data from 1997 to 2004 across Canadian provinces, comparing outcomes before and after the introduction of the universal vaccination program using Poisson regression.