Comparisons in the health and economic assessments of using quadrivalent versus trivalent influenza vaccines: a systematic literature review

Open AccessPublished:November 24, 2022DOI:
      This paper is only available as a PDF. To read, Please Download here.



      Seasonal influenza vaccines protect against three (trivalent influenza vaccine, IIV3) or four (quadrivalent influenza vaccine, IIV4) viruses. IIV4 costs more than IIV3, and there is a tradeoff between incremental cost and protection. This is especially the case in low- and middle-income countries (LMICs) with limited budgets; previous reviews have not identified studies of IIV4-IIV3 comparisons in LMICs. We summarized the literature that compared health and economic outcomes of IIV4 and IIV3, focused on LMICs.


      We systematically searched five databases for articles published before October 6, 2021 that modeled health or economic effects of IIV4 vs. IIV3. We abstracted data and compared findings among countries and models.


      Thirty-eight studies fit our selection criteria, ten included LMICs. Most studies (n=31) reported that IIV4 was cost-saving or cost-effective when compared to IIV3; we observed no difference in health or economic outcomes between LMICs and other countries. Based on cost differences of influenza vaccines, only one study compared coverage of IIV3 with IIV4 and reported that the maximum IIV4 price that would still yield greater public health impact than IIV3 was 13-22% higher than IIV3.


      When vaccination coverage with IIV4 and IIV3 is the same, IIV4 tends to be not only more effective, but more cost-effective than IIV3, even with relatively high price differences between vaccine types. Alternatively, where funding is limited as in most LMICs, higher vaccine coverage can be achieved with IIV3 compared to IIV4, which could result in more favorable health and economic outcomes.

      Key words