Two new modelling studies from Allison Portnoy and colleagues have been published in PLOS Medicine and BMJ Global Health on the economic impact of introducing novel TB vaccines in low- and middle-income countries (LMICs).
In PLOS MEDICINE, the team estimated the impact of introducing novel TB vaccines on gross domestic product (GDP) growth in 105 LMICs. The team adapted an existing macroeconomic model to simulate country-level GDP trends between 2020 and 2080, comparing scenarios for the introduction of hypothetical infant and adolescent/adult vaccines to a no-new-vaccine counterfactual.
Both of these scenarios produced greater cumulative GDP in the modeled countries over the study period, equivalent to $1.6 trillion for the adolescent/adult vaccine and $0.2 trillion for the infant vaccine. These GDP gains were substantially lagged relative to the time of vaccine introduction, particularly for the infant vaccine. GDP gains resulting from vaccine introduction were found to be concentrated in countries with higher current TB incidence and earlier vaccine introduction.
In BMJ Global Health, researchers assessed the potential financial risk protection from introducing novel TB vaccines in 105 LMICs, and how health and economic benefits would be distributed across income quintiles, also following introduction of an infant vaccine and separately for an adolescent/adult vaccine, compared with a no-new-vaccine counterfactual.
Over 2028–2050, the health gains resulting from vaccine introduction were greatest in lower income quintiles, with the poorest 2 quintiles in each country accounting for 56% of total LMIC TB cases averted. Over this period, the infant vaccine was estimated to avert US$5.9 billion in patient-incurred total costs, and the adolescent/adult vaccine was estimated to avert US$38.9 billion. Additionally, 3.7 million fewer households were projected to face catastrophic costs with the infant vaccine and 22.9 million with the adolescent/adult vaccine, with 66% of gains accruing in the poorest 2 income quintiles.