Examining the Relationship between Precipitation, Drainage Connectivity, and Malaria Incidence in India

Malaria continues to pose a major public health challenge in India, where climatic variability and infrastructural deficiencies contribute to favorable breeding conditions for disease vectors. While stagnant water has long been recognized as a driver of mosquito proliferation, empirical, population-level evidence linking rainfall and drainage infrastructure to malaria transmission in India remains limited. This study examines the relationship between environmental factors and malaria incidence in India, focusing on average annual precipitation and household drainage infrastructure as potential drivers of disease transmission. Using national-level data from 1996 to 2011 for precipitation and state-level data from 2011 for drainage connectivity, the study applies Pearson correlation and linear regression to assess associations with the Annual Parasite Incidence (API), a standardized measure of malaria prevalence. The results indicate a statistically significant positive correlation between higher rainfall and increased malaria cases over time, as well as a significant association between inadequate drainage (measured as the percentage of households with open or no wastewater connectivity) and elevated API across Indian states. While the explanatory power of each model is modest, both tests reject the null hypotheses and identify environmental conditions that contribute meaningfully to disease burden. The study provides quantitative evidence linking infrastructural and climatic factors to public health outcomes, offering a statistical foundation for targeted policy interventions. These findings underscore the importance of climate-responsive urban planning and investment in drainage systems as part of a broader strategy to reduce the incidence of malaria (and other vector-borne diseases) in endemic regions.