Field Investigation of Two Urban Cases of Severe Fever with Thrombocytopenia Syndrome — Nanjing City, Jiangsu Province, China, 2025

What is already known about this topic?: (DBV), traditionally endemic in rural agricultural and tea plantation areas. Reported cases of SFTS linked to tick bites are sparse in China's core urban areas. What is added by this report?: This report documents two SFTS cases infected in well-afforested residential zones in the urban areas of Nanjing. Emergency tick monitoring identified DBV-positive ticks in related green spaces, suggesting the sporadic presence of natural foci in specific urban environments. What are the implications for public health practice?: This report provides initial evidence of DBV transmission in urban areas with suitable tick habitats, which increases the risk of infection in densely populated and well-afforested urban settings. This report highlights the need for clinicians to recognize SFTS cases without a clear history of agricultural or rural exposure. To mitigate urban SFTS transmission risk, a multipronged strategy is required that encompasses strengthened surveillance, integrated vector control, public education, and clinical vigilance, including early recognition and optimized referral pathways.