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? Severe fever with thrombocytopenia syndrome (SFTS) is a highly fatal tick-borne viral disease caused by Dabie bandavirus (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.