Abstract
Despite significant progress in the last 20 years in reducing the case-incidence of malaria, it remains a large public health burden. Ghana, one of three countries in the Malaria Vaccine Implementation programme, is among the 15 highest burden malaria countries in the world and accounted for 1.9% of global deaths and 2.1% of global cases in 2020.
In October 2021, the World Health Organisation (WHO) recommended widespread use of the RTS, S/AS01 vaccine. Vaccines have wide societal benefits (commonly referred to as broader value elements), such as increasing the productivity of a working age patient or improving educational outcomes of children. However, these benefits, particularly the impact on education, are often not included in HTA, leaving vaccines at risk of being undervalued. This research aims to contribute to the literature by incorporating educational outcomes, and the impact of education on lifetime income, within a cost-effectiveness analysis (CEA).
A literature review was performed to inform the economic analysis undertaken. A Markov model was developed to simulate malaria progression in a hypothetical Ghanian birth cohort. Parameters were based on published data. The impact of malaria on education and subsequently lifetime income was modelled using two different approaches. The first, valued the opportunity cost of a child’s time as a function of days of education lost due to infection within the model. The second approach valued the opportunity cost as a function of days of education gained. Both healthcare and societal perspectives were explored. Health outcomes were measured in disability-adjusted life years (DALYs) averted and costed in 2019 USD. Incremental cost-effectiveness ratios (ICERs) were calculated, and sensitivity analyses were conducted. One times GDP per capita per DALY averted was used as the cost-effectiveness threshold.
The results show that vaccinating children was very cost-effective from both a societal and healthcare perspective. When a child’s time was valued using days of education lost, the vaccine resulted in a decrease in lifetime income across the cohort. This is a result of more individuals surviving and having more opportunities to pass through the malaria health states. However, when a child’s time was valued using days of education gained, the vaccine resulted in more days of education gained and an increase in lifetime income across the cohort. Overall, the vaccine’s ICER was $6.08 per DALY averted from a healthcare perspective, and, from a societal perspective, the vaccine was considered dominant versus standard of care (SoC). This result was robust to changes in most variables, including vaccine price and efficacy. However, the main driver of the more favourable ICER from the societal perspective was the estimation of lost productivity due to illness in adults, not the inclusion of education.