Epidemic characteristics and risk factors of severe fever with thrombocytopenia syndrome in Zhaoyuan City, Shandong Province / 中华地方病学杂志

ABSTRACT

Objective:To understand the epidemic characteristics and risk factors of severe fever with thrombocytopenia syndrome (SFTS) in Zhaoyuan City, and to provide basis for the improvement of prevention and control strategies.Methods:Retrospective analysis was performed to collect the SFTS surveillance data and epidemiological investigation results of confirmed cases in Zhaoyuan City from 2011 to 2018 from the "Infectious Disease Report Information Management System of the China Disease Prevention and Control Information System", and the general situation and epidemiological characteristics, onset and treatment, clinical manifestations and contact history of SFTS cases were analyzed by descriptive epidemiology method; 60 cases of SFTS confirmed cases and 120 healthy people in the same village, same sex, and same age group as the confirmed case were selected by case-control study to analyze the risk factors of SFTS.Results:A total of 140 confirmed SFTS cases were reported in Zhaoyuan City from 2011 to 2018, with a fatality rate of 18.57% (27/140); the onset time was mainly from May to August, accounting for 83.57% (117/140); the age of onset was mainly 50 - 80 years old, accounting for 90.00%(126/140); the sex ratio of men to women was 1.06 ∶ 1.00 (72 ∶ 68); the occupation distribution was dominated by farmers, accounting for 92.14% (129/140). In 140 cases of SFTS, the average time intervals from onset to first visit and from first visit to confirmation of diagnosis were 4 and 6 days, respectively; and the average medical visit history from onset to diagnosis was 2 times, 60.71% (85/140) of the cases were first diagnosed by township medical institutions, 86.43% (121/140) of the cases were diagnosed by municipal hospitals; the first symptom was fever, which accounted for 92.86% (130/140). The logistic regression analysis showed that domestic animals [odds ratio ( OR)=9.209, 95% confidence interval ( CI) 2.064-41.083] and tick bites ( OR = 16.818, 95% CI 1.553 - 182.164) were risk factors for SFTS. Conclusions:The onset time of SFTS is mainly from May to August in Zhaoyuan City, and farmers over 50 years old are the key population; domestic animals and tick bites are the risk factors for the onset of SFTS. The publicity and health education of SFTS prevention and control knowledge for key populations should be strengthened.