Fatal Rickettsia parkeri Rickettsiosis in Immunocompromised Pediatric Patient, Georgia, USA, 2025.

We describe a fatal Rickettsia parkeri rickettsiosis case in a 3-year-old boy in Georgia, USA, receiving chemotherapy for B-cell acute lymphoblastic leukemia, hospitalized with febrile neutropenia. Plasma microbial cell-free DNA sequencing confirmed the diagnosis. This report highlights the need to maintain suspicion for tickborne diseases in immunocompromised hosts in some settings.