Prediction of measles elimination in Côte d'Ivoire by 2030.

Abstract

Background: The WHO African Region Strategic Plan for Immunisation 2021-2030 aims to eliminate measles in at least 80% of countries by 2030. What could the situation in Côte d'Ivoire be like?

Aim: To predict the incidence of measles by 2030.

Setting: Côte d'Ivoire, a country in West Africa.

Methods: National routine measles surveillance data were analysed using seasonal time series models. Stationarity was assessed using standard unit root tests, and seasonality was addressed through appropriate differentiation. Structural breaks were examined using break and stability tests, which identified a major break around 2020. An Autoregressive Integrated Moving Average (ARIMA) model incorporating an intervention variable was adjusted to account for this change. Model performance was evaluated using cross-validation and compared to a naive seasonal benchmark. Projections were generated through 2030. The annual incidence per 1 000 000 population was estimated.

Results: A significant structural break around 2020 was identified. Projections show a slight downward trend in incidence for the overall population. However, among children, an increase in incidence from 146 to 164 by 2030 was observed. During cross-validation, the ARIMA model with intervention did not outperform the naive seasonal benchmark for short-term forecasts.

Conclusion: By 2030, Côte d'Ivoire will not have eliminated measles, with a high incidence among children. Sustained high vaccination coverage, strengthened surveillance, and scenario-based planning remain critical to achieving measles elimination.

Contribution: The study guides decision-makers on the prospects and the necessity of adopting innovative strategies aimed at eliminating measles.