Abstract
WHAT IS ALREADY KNOWN ABOUT THIS TOPIC? Dengue fever represents one of the most prevalent viral infections annually affecting the general population in endemic regions. It is widely recognized as an acute self-limiting disease, with the virus typically being completely cleared within 2-3 weeks post-infection, without establishing long-term latency. The current consensus is that primary infection with a specific serotype confers lifelong type-specific immunity, thereby preventing reinfection with an identical dengue virus serotype. WHAT IS ADDED BY THIS REPORT? We report the case of a patient with leukemia who developed a confirmed dengue virus serotype 1 (DENV-1) infection during chemotherapy and targeted therapy. Notably, 6 months after the resolution of the initial infection, the same patient tested positive again for DENV-1 nucleic acid while undergoing intensive immunosuppression following allogeneic hematopoietic stem cell transplantation. WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE? For patients undergoing hematopoietic stem cell transplantation and receiving immunosuppressive therapy, clinicians should be vigilant about the potential for persistent dengue infection, particularly in dengue-endemic regions. Furthermore, implementing prolonged serological monitoring post-infection is also crucial for the clinical management of this patient population.