A Comparison of Clinical and Laboratory Features of Crimean-Congo Hemorrhagic Fever in Children and Adults: A Retrospective Single-Center Cohort Study and Literature Review.

Crimean-Congo hemorrhagic fever (CCHF) is a major emerging infectious disease threat, and children are reported to have a milder disease course compared with adults, in contrast to other viral hemorrhagic fevers. The aim of this study was to compare adult and pediatric patients with CCHF to improve understanding of pathogenesis and the natural history of the disease. A retrospective analysis of all children and adults admitted with confirmed CCHF between 2011 and 2020. Epidemiological, clinical, and laboratory features were collated on proformas, together with clinical management details. The Severity Grading Score (SGS) system was used to stratify mortality risk. Data from children were compared with adults in the same center and with other published pediatric cohort studies. A total of 47 children with a median (ranges) age of 14 (2-17) years and 176 adults with a median (ranges) age of 52 (18-83) years with confirmed CCHF were included. The most frequent symptoms in adults were fever, muscle-joint pain, headache, nausea, and vomiting; the most frequent in children were fever, anorexia, nausea, vomiting, and abdominal pain. Adults had lower lymphocyte and platelet counts and higher liver transaminase and creatinine levels than children. SGS values were lower in children, but 97.9% children received ribavirin compared with 8.5% of adults ( < 0.001), and they had associated longer median lengths of hospital admission (10 vs. 7 days, < 0.001). Mortality of 1 out of 47 (2.1%) children was similar to 11 other cohorts reported in Türkiye and lower than 13.1% in adults (23/176) in the same center ( = 0.059). Children have lower CCHF-related mortality, less severe disease, and different clinical syndromes at presentation. The majority of published case definitions for screening for CCHF in the main endemic countries do not differentiate between adults and children and omit four of the five most common presenting features in children.