Indigenous Plasmodium vivax upsurge in the Eastern Mediterranean, Western Pacific, and South East Asia regions - beyond the constant culpability of climate change, COVID-19, and armed conflicts.

Abstract

Controlling Plasmodium vivax presents greater challenges compared to Plasmodium falciparum. Here, we analyzed epidemiological data on indigenous P. vivax cases from the Eastern Mediterranean, Southeast Asia, and Western Pacific regions in recent years. Significant upsurges are observed in more than half of the countries within these regions. In Papua New Guinea and Yemen, the increase has been consistent since 2015, while others, including Indonesia and Pakistan, have experienced sharp rises between 2020 and 2023 (e.g., +100 % and +83.4 %). Notably, in countries like Thailand, initially targeted by the WHO E-2025 elimination initiative, achieving elimination by 2025 appears unlikely. Factors like the COVID-19 pandemic, armed conflicts, and, more recently, climate change, do not fully resolve the reasons for resurgence in countries like Papua New Guinea, where additional issues such as chloroquine resistance must also be addressed. A compartmentalized approach is essential to tackle the P. vivax resurgence and achieve meaningful progress effectively.