Association between temperature and malaria (1959-2019): a systematic review and meta-analysis

Malaria remains a significant global health challenge, with temperature playing a critical role in transmission dynamics by affecting parasite development, mosquito longevity, and vectorial capacity. This systematic review and meta-analysis aimed to quantify the association between ambient temperature and malaria incidence across diverse geographical and ecological contexts, informing climate-informed control strategies.

Following PRISMA guidelines, we systematically searched PubMed/MEDLINE, Embase, Scopus, and Web of Science from inception to September 2024. Studies examining correlations between temperature metrics and malaria outcomes with a minimum 12-month follow-up were included. Methodological quality was assessed using a modified version of the Newcastle-Ottawa Scale. Random-effects meta-analysis was conducted to calculate pooled correlation coefficients and 95% confidence intervals.

Eleven studies from Africa and Asia spanning 1959-2019 were included, representing diverse transmission ecologies from temperate China to tropical Africa. Mean temperature showed a moderate positive correlation with malaria incidence (r = 0.417, 95% CI: 0.098-0.735, p = 0.01). Minimum temperature demonstrated the strongest and most consistent association with malaria test positivity rates (r = 0.454, 95% CI: 0.358-0.549, p < 0.001), with all 11 studies showing statistically significant positive correlations. Maximum temperature exhibited weaker relationships (r = 0.356, 95% CI: 0.263-0.450 for positivity rates). Substantial heterogeneity was observed across all analyses (I² > 99%), reflecting regional variations in temperature-malaria dynamics.

Temperature, particularly minimum temperature, significantly influences malaria transmission across diverse epidemiological settings. The stronger association with minimum temperature is concerning, given that climate change disproportionately affects nighttime temperatures. The substantial heterogeneity underscores the need for locally tailored climate-informed malaria control strategies. These findings support integrating temperature monitoring, especially minimum temperature thresholds, into malaria surveillance systems and early warning programs as climate change progresses.