Evaluation of rotavirus, pneumococcal conjugate and human papillomavirus vaccination in four Pacific island countries: A cost-effectiveness modelling study

BackgroundTo assist decision making on the introduction of rotavirus vaccine (RVV), pneumococcal conjugate vaccine (PCV) and human papillomavirus vaccine (HPVV), cost-effectiveness and budget impact evaluations were undertaken in Samoa, Tonga, Tuvalu and Vanuatu. MethodsA proportionate outcomes model was used to evaluate vaccine introduction in each country from a health systems perspective, using country-specific data supplemented with regional and global estimates. A 10-year vaccination program was modelled from 2021, with costs and outcomes (disability-adjusted life years; DALYs) summed over a life-time horizon and discounted at 3%. Vaccine dose costs were based on Pan American Health Organization (PAHO) Revolving Fund prices, with lower priced products also explored. FindingsIntroduction of all three vaccines in all countries could prevent over 1,000 deaths over the lifetimes of the vaccinated cohorts. The cost per DALY averted at PAHO Revolving Fund prices ranged from 43% - 73% of the per capita gross domestic product (GDP) in each country, and 15% - 58% for lower-priced vaccines. The budget impact ranged from 359% (Samoa) to 1,368% (Vanuatu) of the 2019 vaccine budgets, and 149% (Samoa) to 775% (Vanuatu) for lower-priced vaccines. Cost-effectiveness results were most sensitive to disease burden, discount rate, vaccine efficacy, and program costs. InterpretationDevelopment partner-supported introduction of HPVV, PCV and RVV may represent good value for money in Samoa, Tonga, Tuvalu and Vanuatu, depending on willingness to pay thresholds, but will place considerable burden on immunisation budgets. Financial sustainability requires increases in immunisation budgets and negotiation of affordable vaccine prices. FundingAsian Development Bank.