Epidemiologic analysis on severe fever with thrombocytopenia syndrome in Zhejiang Province,2014
MA Ting1, 2, SUN Ji-min2, GONG Zhen-yu2, ZHANG Rong2, YAN Jian-bo3, REN Yi4, CHANG Yue5, GU Shi-ping6, SHI Xu-guang2, REN Jiang-ping2, JIANG Jian-min2
1.Medical School, Ningbo University, Ningbo 315211, China; 2.Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou 310051, China; 3.Zhoushan Center for Disease Control and Prevention, Zhoushan 316021, China; 4.Daishan Center for Disease Control and Prevention, Zhoushan 316200, China; 5.Taizhou Center for Disease Control and Prevention, Taizhou 318000, China; 6.Anji Center for Disease Control and Prevention, Huzhou 313000, China
Abstract：We analyzed the epidemic characteristics of severe fever with thrombocytopenia syndrome (SFTS) in Zhejiang Province in the year of 2014 to provide the scientific evidence for prevention and control of the disease. In 2014, 57 SFTS cases were reported in Zhejiang Province, with fatality rate as 17.54% (10/57). Epidemic peak was from May to August (73.68%). The age of the cases ranged from 0.5 to 84 years old with the median age of (58.75±16.30). Additionally, the median age of the death cases was 71 with the highest fatality rate in the 65-75 age group (χ2=10.437, P=0.015<0.05). The most cases were farmers (89.29%). The 53.85% of patients had the history of outdoor activities, such as farming, mowing the lawn and tea plucking, two weeks before the onset of SFTS; 87.03% of the cases engaged in different kinds of work which was associated with agriculture; 29.09% of the patients had been exposed to ticks; 54.90% of the cases engaged in raising animals at home; 51.06% of the patients had been exposed to mouse. The overwhelming majority of cases experienced fever with the body temperature form 37.7 ℃ to 41 ℃, which was the major onset symptom of 82.14% cases. Meanwhile, most patients also experienced fatigue, chill, myodynia and other non-specific symptoms but all appeared progressive thrombocytopenia and leucopenia. Bleeding gums symptoms showed significant statistical differences between survival and death cases (χ2=4.114, P=0.043<0.05). The median time of the survival cases from illness onset to confirmation was 5.5 days, and for the death cases was 7.5 days. The median time from confirmation to death was 3.5 days. What’s more, 2 cases were confirmed after death. In conclusion, SFTS in Zhejiang Province has certain regional and seasonal characteristics. Most cases were older farmers. Early diagnosis and treatment may have important implications to reducing SFTS mortality.
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2015, Vol. 31 
