Plasmodium knowlesi and global changes: socio-ecological drivers and challenges

Plasmodium knowlesi, a malaria species predominantly found in Southeast Asia, is influenced by climate change in its transmission dynamics. Variations in temperature and precipitation impact both mosquito vectors and the parasites they carry. Additionally, deforestation and alterations in land use, often driven by climate change, facilitate the zoonotic transmission of the disease from simian hosts to humans. Climatic fluctuations also influence human and community behaviours, potentially altering exposure risks. Although increased awareness of climate risks may prompt behavioural changes, the attitude behaviour gap-where awareness does not necessarily translate into action-remains a significant challenge. Environmental alterations can transform mosquito habitats and breeding patterns, thereby influencing disease transmission. Community responses may create new transmission zones or modify existing ones. Furthermore, climate change may alter the distribution of natural hosts for Plasmodium knowlesi, affecting its transmission dynamics. Understanding these interconnections is crucial for addressing the impact of climate change on malaria transmission in general and specifically P. knowlesi. This review examines the spread of P. knowlesi in the context of climate change, land use changes, human behaviour and activities, human-macaque-mosquito interaction, other contributing factors, and challenges to provide insight for future research on controlling P. knowlesi in regions where interactions among humans, monkeys, and mosquitoes are intensifying due to environmental and developmental changes.