Climate Change and Malaria: Impact, Vulnerability, and Adaptation Pathways in Homa Bay County, Kenya

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DOI: 10.21522/TIJAR.2014.13.01.Art014

Authors : Jacob Bulimo Khaoya, Collins Ouma, Titus Oladapo Okareh

Abstract:

This paper presents the relationship between climate change (temperature, rainfall, humidity) and incidence of malaria in Homabay County, Kenya. Climate change impacts, household exposure, sensitivity, and adaptive capacity were analysed to inform policy. The study combined ecological time-series analysis, household surveys, and key informant interviews. It analysed climate and morbidity data from 2010-2024, supplemented with primary data from 401 households and insights from 19 stakeholders. Standardized questionnaires and in-depth interviews guided data collection. The ARDL models assessed short and long-run climate effects on malaria, logistic regression examined determinants of household vulnerability, and thematic analysis generated qualitative insights. The findings showed malaria cases averaged 23,082 per month (SD = 13,402), mean temperature 23.3°C (SD = 1), rainfall 117.7 mm (SD = 67), and humidity 74%. The long-run model showed a significant baseline incidence and a highly significant first-month lag (IRR ≈ 1.92). Similarly, short-run results confirmed strong persistence, with first differenced lag significant (IRR ≈ 1.82). The household survey showed an overall moderate vulnerability to malaria (median 0.35), driven by high exposure, moderate sensitivity and adaptive capacity. Sensitivity linked to older household-head, low education, poor housing, and climate-dependent livelihoods significantly increased odds of malaria by 52%. Exposure had a positive effect on malaria incidence (OR ≈ 1.29) while stronger adaptive capacity lowered malaria risk. The study concluded that climate change has a significant impact on malaria in Homa Bay County. It highlights the need for real-time climate-health early warning systems by integrating meteorological data into IDSR for timely outbreak detection.

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