Cost-effectiveness and budget impact analyses for the prioritisation of the four available rotavirus vaccines in the national immunisation programme in Thailand

Abstract

Background: Rotavirus is a major cause of diarrhoea in children less than five years old in Thailand. Vaccination has been shown to be an effective intervention to prevent rotavirus infections but has yet to be enlisted in the national immunisation programme. This study aimed to assess the cost-utility of introducing rotavirus vaccines, taking all WHO-prequalified vaccines into consideration. Methods: A cost-utility analysis was performed using a transmission dynamic model to estimate, from a societal perspective, the costs and outcomes of four WHO-prequalified rotavirus vaccines: Rotarix®, RotaTeq®, ROTAVAC® and ROTASIIL®. The model was used to simulate the impact of introducing the vaccines among children aged < 1 year and compare this with no rotavirus vaccination. The vaccination programme was considered to be cost-effective if the incremental cost-effectiveness ratio was less than a threshold of USD 5,110 per QALY gained. Results: Overall, without the vaccine, the model predicted the average annual incidence of rotavirus to be 312,118 cases. With rotavirus vaccination at a coverage of more than 95%, the average number of rotavirus cases averted was estimated to be 144,299 per year. All rotavirus vaccines were cost-saving. ROTASIIL® was the most cost-saving option, followed by ROTAVAC®, Rotarix® and RotaTeq®, providing average cost-savings of USD 32, 31, 23 and 22 million per year, respectively, with 999 QALYs gained. All vaccines remained cost-saving with lower QALYs gained, even when ignoring indirect beneficial effects. The net saving to the healthcare system when implementing any one of these vaccines would be between USD 13 and 33 million per year. Conclusion: Rotavirus vaccines should be included in the national vaccination programme in Thailand. Implementing any one of these four WHO-prequalified vaccines would reduce government healthcare spending while yielding health benefits to the population.