三起家庭感染发热伴血小板减少综合征疫情暴露风险矩阵法分析

Analysis of three family clusters of severe fever with thrombocytopenia syndrome by exposure risk matrix

目的应用暴露风险矩阵法分析三起家庭感染发热伴血小板减少综合征(SFTS)疫情,为预防控制SFTS提供依据。方法收集2014-2016年临海市报告的7例确诊SFTS病例现场流行病学个案调查和临床病案资料,采用暴露风险矩阵法分析病例发病前2周的环境暴露风险、活动时间和防护情况等,分析可能的传播途径。结果第一起疫情涉及3例病例,为姐妹;其中2例曾一起上山采茶,被蜱虫叮咬感染的可能性较大,分别为60%和75%;另一例去探病后(与病例无身体接触)在其生活地被若蜱叮咬感染的可能性较大,为74%。第二起疫情涉及2例病例,为母子;在现居地被蜱虫叮咬感染的可能性较大,分别为100%和80%。第三起疫情涉及2例病例,为夫妻;妻子在山上摘杨梅时被蜱虫叮咬感染的可能性较大,为60%;在现居地被蜱虫叮咬感染的可能性为40%;丈夫在照料妻子时通过接触其体液或血液感染的可能性较大,为44%,在山上摘杨梅被蜱虫叮咬感染的可能性为33%。结论2014-2016年临海市报告的三起家庭聚集性SFTS疫情共7例病例,有6例因蜱虫叮咬感染的可能性超过50%,另1例虽然密切接触病例体液或血液感染的可能性较大,但也不能排除蜱虫叮咬感染的可能。

Objective To analyze three events of severe fever with thrombocytopenia syndrome(SFTS)among family members by exposure risk matrix,so as to provide reference for SFTS prevention and control.Methods The field investigation and clinical data of seven confirmed cases with SFTS reported in Linhai from 2014 to 2016 were collected.Exposure risk matrix was used to list the risk of exposure two weeks before the onset,such as the environment,duration of activity and protection,and evaluate the possible routes of transmission.Results The first event involved three sisters.Two of them had plucked tea together on a hill,and the possibility of infection through tick bites were 60%and 75%,respectively.Another sister was more likely to be infected by ticks in her residence after visiting her sister(no physical contact with the sick sister),with a possibility of 74%.The second event involved two cases(mother and son).They were more likely to be infected by ticks in the current residential area,and the possibility were 100%and 80%,respectively.The third event involved two cases(husband and wife).The wife had 60%possibility of being infected by the ticks on the hill she picked arbutus,and 40%by the ticks in her residence.The husband was most likely to be infected through contacting with body fluids or blood of his wife(44%),then through the ticks on the hill he picked arbutus(33%).Conclusion Among seven cases with SFTS reported in Linhai from 2014 to 2016,six cases have more than 50%possibility of being infected by tick bites;one case has higher possibility of being infected by contacting with body fluids or blood of a patient,but tick bites could not be ruled out.