Quantifying Climate Change Impacts on Waterborne Pathogen Diversity and Abundance in Africa: A Systematic Review

Africa, despite contributing minimally to global greenhouse gas emissions, disproportionately bears the brunt of climate change’s consequences. This systematic review quantifies the impact of shifting climatic conditions on waterborne pathogen diversity and abundance in this ecologically diverse continent. We analyze 88 indexed research articles published between 1996 and 2024 using PRISMA guidelines.
Key Findings:
Increased diversity: A 1°C temperature rise significantly increased waterborne pathogen richness by 18.2% (95% CI: 12.7-23.8%). This aligns with observed correlations between rising temperatures and expanded geographic ranges of Vibrio cholerae, Cryptosporidium, and Shigella species.
Altered abundance: Extreme precipitation events like floods (OR: 4.2, 95% CI: 2.8-6.1) and droughts (OR: 2.7, 95% CI: 1.8-4.0) were associated with significantly higher prevalence of diarrhoeal diseases caused by pathogens like rotavirus and Giardia lamblia.
Regional variations: Rainfall patterns played a nuanced role, with increased variability (CV) significantly associated with higher richness of bacteria (β = 0.15, p < 0.001) in arid regions but negatively affecting protozoan diversity (β = -0.08, p < 0.05) in tropical zones.
Socioeconomic factors: Low income levels (β = -0.22, p < 0.01) and inadequate sanitation infrastructure (β = -0.31, p < 0.001) were strongly associated with decreased waterborne pathogen diversity, highlighting the need for integrated interventions.
Future Directions:
Our findings underscore the urgency of developing predictive models incorporating climate and socioeconomic data to forecast pathogen dynamics and guide targeted public health interventions. Additionally, research efforts should prioritize elucidating the specific mechanisms that underly climate-driven changes in pathogen diversity and abundance. This enhanced understanding will inform tailored adaptation strategies for sustainable development and resilient water management in Africa.