One-way sensitivity analyses (hourly wage).

<p>One-way sensitivity analyses (hourly wage).</p

An Assessment of the Expected Cost-Effectiveness of Quadrivalent Influenza Vaccines in Ontario, Canada Using a Static Model

<div><p>Ontario, Canada, immunizes against influenza using a trivalent inactivated influenza vaccine (IIV3) under a Universal Influenza Immunization Program (UIIP). The UIIP offers IIV3 free-of-charge to all Ontarians over 6 months of age. A newly approved quadrivalent inactivated influenza vaccine (IIV4) offers wider protection against influenza B disease. We explored the expected cost-utility and budget impact of replacing IIV3 with IIV4, within the context of Ontario’s UIIP, using a probabilistic and static cost-utility model. Wherever possible, epidemiological and cost data were obtained from Ontario sources. Canadian or U.S. sources were used when Ontario data were not available. Vaccine efficacy for IIV3 was obtained from the literature. IIV4 efficacy was derived from meta-analysis of strain-specific vaccine efficacy. Conservatively, herd protection was not considered. In the base case, we used IIV3 and IIV4 prices of $5.5/dose and$7/dose, respectively. We conducted a sensitivity analysis on the price of IIV4, as well as standard univariate and multivariate statistical uncertainty analyses. Over a typical influenza season, relative to IIV3, IIV4 is expected to avert an additional 2,516 influenza cases, 1,683 influenza-associated medical visits, 27 influenza-associated hospitalizations, and 5 influenza-associated deaths. From a societal perspective, IIV4 would generate 76 more Quality Adjusted Life Years (QALYs) and a net societal budget impact of $4,784,112. The incremental cost effectiveness ratio for this comparison was$63,773/QALY. IIV4 remains cost-effective up to a 53% price premium over IIV3. A probabilistic sensitivity analysis showed that IIV4 was cost-effective with a probability of 65% for a threshold of $100,000/QALY gained. IIV4 is expected to achieve reductions in influenza-related morbidity and mortality compared to IIV3. Despite not accounting for herd protection, IIV4 is still expected to be a cost-effective alternative to IIV3 up to a price premium of 53%. Our conclusions were robust in the face of sensitivity analyses.</p></div

Model inputs.

<p>Model inputs.</p

Threshold analysis: Incremental cost-effectiveness ratio (ICER) versus price of IIV4.

<p>Threshold analysis: Incremental cost-effectiveness ratio (ICER) versus price of IIV4.</p

Incremental cost-effectiveness ratios of IIV4 versus IIV3 by age group.

<p>Incremental cost-effectiveness ratios of IIV4 versus IIV3 by age group.</p

Health outcomes avoided with IIV4 in Ontario by age group.

<p>Health outcomes avoided with IIV4 in Ontario by age group.</p

Deterministic sensitivity analysis (societal perspective).

<p>Deterministic sensitivity analysis (societal perspective).</p

Additional file 2: of Cost-effectiveness evaluation of quadrivalent influenza vaccines for seasonal influenza prevention: a dynamic modeling study of Canada and the United Kingdom

Age-specific mean health outcomes per season in Canada. (DOCX 51 kb

Annual estimates of economic burden using direct medical costs, lost productivity and monetary value of quality adjusted life years (QALYs) lost based on all-cause influenza-attributed mortality by age group in millions of US Dollars averaged over five respiratory seasons.

<p>Annual estimates of economic burden using direct medical costs, lost productivity and monetary value of quality adjusted life years (QALYs) lost based on all-cause influenza-attributed mortality by age group in millions of US Dollars averaged over five respiratory seasons.</p

Annual estimates of influenza-attributed all-cause mortality by risk and age group averaged over five respiratory seasons.

<p>Annual estimates of influenza-attributed all-cause mortality by risk and age group averaged over five respiratory seasons.</p