Abstract: Abstract: Objective To analyze the clinical characteristics of severe fever with thrombocytopenia syndrome (SFTS)and provide more theoretical basis for the treatment. Methods A retrospective analysis was performed on 74 confirmed cases collected from the 154 Hospital, Chinese People’s Liberation Army, Xinyang City, Henan Province from August 2017 to August 2018. The patients were divided into mild group (58 cases) and severe group (16 cases), and the differences in the clinical features and laboratory test were compared between the two groups, including white blood count (WBC), platelet (PLT), aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine kinase (CK), lactate dehydrogenase (LDH)and blood urea nitrogen (BUN). Multiple Logistic regression analysis was conducted to explore the risk factors in SFTS patients. Results The epidemiological data showed that most of patients were older farmers. Clinical features of SFTS patients contained fever, loss of appetite, fatigue, nausea, muscle pain and lymphadenectasis. The incidences of the loss of appetite, diarrhea, unconsciousness, chest distress and asthma were significantly higher in severe group than those in mild group (P＜0.05). The laboratory test showed that CK and BUN levels were significantly higher in severe group than those in mild group (P＜0.05), but there were no significant differences in the other indictors between the two groups. Logistic regression analysis showed that loss of appetite (OR=5.207, 95%CI：1.039-26.082) and CK≥200 U/L (OR=4.446，95%CI：1.231-16.058) were risk factors leading to the progression of disease from mild to severe. Conclusion The loss of appetite and increased level of CK are risk factors for the aggravation of the disease. These factors should be controlled in order to reduce mortality.

Key words: bunyaviridae infections, severe fever with thrombocytopenia syndrome, hepatic insufficiency, clinical feature