The Vector-Proofing Gap in Sponge City Design: Implications for Arboviral Risk Under Climate Adaptation - Guangdong Province, China, 2025.

This perspective examines the July 2025 chikungunya fever outbreak in Guangdong Province as a sentinel event exposing a practical gap in climate-resilient urban design. As of July 26, 2025, Guangdong had reported 4,824 confirmed cases, 98.5% in Foshan City and most concentrated in Shunde District. Although sponge-city green stormwater infrastructure (GSI) strengthens urban flood resilience, its detention and retention features can also generate cryptic, hard-to-inspect water habitats that sustain Aedes mosquito breeding under hot, humid conditions when post-storm dry-down and maintenance fall short. This perspective synthesizes outbreak context, China's sponge-city evaluation metrics, and vector-ecology thresholds to define a vector-proofing gap: prevailing sponge-city guidance excels in hydrological performance but typically lacks explicit, measurable constraints on water residence time and inspectability tied directly to vector risk. An operational vector-proofing framework is proposed that 1) translates entomological risk into engineering indicators (e.g., post-storm dry-down within 48-72 hours where feasible, access/inspectability, and trigger-based maintenance), 2) embeds vector impact assessment across the project lifecycle, and 3) clarifies cross-sector responsibilities among housing/urban-rural development, water resources, and health agencies. Aligning hydrological and entomological objectives can reduce the likelihood that climate adaptation investments inadvertently shift risk from flooding to arboviral transmission.