COST-EFFECTIVENESS OF HAEMOPHILUS INFLUENZAE TYPE B VACCINE IN VIETNAM
Candidate for the Lee B. Lusted Student Prize Competition
Method: We used a static cohort model to estimate the costs and effectiveness of the two scenarios. The 2011 Vietnamese birth cohort was modeled for five years. The burden of Hib diseases was estimated from local epidemiologic data and relevant literature. We subtracted the future treatment costs averted due to Hib vaccine from the incremental vaccine delivery costs to estimate the net costs of vaccine introduction. Vaccine delivery costs, including vaccine costs, injection supplies and program implementation costs, were calculated based on government reports and 2013 prices. A prospective cost-of-illness study was conducted among age four and under pneumonia and meningitis patients in Bach Mai hospital to produce estimates of direct medical, non-medical and time costs. The human capital approach was employed to estimate productivity losses. The net costs of Hib vaccination were divided by several measures of incremental effectiveness (Hib cases, deaths, and disability-adjusted life years prevented) to get incremental cost-effectiveness ratios (ICERs).
Result: Over five years the introduction of Hib vaccine prevented 6,459 discounted Hib cases, 1,227 discounted deaths and 25,125 discounted DALYs. From the societal perspective, the ICERs per discounted case, death and DALY prevented were USD 430, USD 2,265, and USD 111, respectively. From the government perspective, the Hib vaccine program was cost-saving as it reduced government costs by USD 422,555 The base-case break-even vaccine price was USD 2.12. Although the Hib vaccine program was most sensitive to pneumonia incidence, it remained cost-effective in all sensitivity analyses; that is, the ICER per DALY remained smaller than Vietnam’s 2011 GDP.
Conclusion: According to the WHO recommended threshold, the Hib vaccine program was highly cost-effective from the societal perspective and at the current co-financing rate it was cost-saving to the government. However, the affordability and sustainability of the Hib vaccine program is unclear after 2015 because the government will incur a six-fold increase in its vaccine budget if it pays the full 2013 vaccine price. In addition, the variability of vaccine market prices adds an element of uncertainty. Increased government commitment and improved resource allocation decision making will be necessary to retain this cost-effective program.