Quantify the burden of disease and economic losses attributable to unsafe water, sanitation, and hygiene (WASH) systems globally, with specific focus on how infrastructure invisibility perpetuates underinvestment in the poorest regions.

Analysis of WHO/UNICEF Joint Monitoring Programme (JMP) data across 195 countries, cross-referenced with IHME Global Burden of Disease Study 2024 for attributable mortality and disability. Water security vulnerability assessment using Climate Hazards Indx integrated with World Bank poverty mapping. Cost-benefit analysis of WASH interventions from 50 randomized controlled trials via systematic review and meta-analysis.

5 billion lack safely managed sanitation. These systems are 'invisible infrastructure' — they work silently until they fail catastrophically. 26 million deaths annually, yet receives less than 1% of global health R&D funding. In Sub-Saharan Africa, 40% of water supplies fail within 5 years due to deferred maintenance.

The economic cost of poor WASH is estimated at 5-10% of GDP in LMIC nations through healthcare costs, lost productivity, and reduced school attendance. 4 billion additional people will live in water-scarce regions.