title: Clinical characteristics and risk factors of an outbreak with scrub typhus in previously unrecognized areas, Jiangsu province, China 2013.
abstract: Scrub typhus, caused by Orientia tsutsugamushi, has emerged recently in Jingjiang City, China where the disease had not been known to exist. We analyzed epidemiological data, clinical characteristics and risk factors of scrub typhus outbreak in Jingjiang City, 2013. The 271 clinically diagnosed patients were predominantly farmers 50 to 69 years old and the peak of onset was early to mid-November. For the 187 laboratory-confirmed cases, the major clinical manifestations of the patients were fever (100%), eschar (88.2%), rash (87.7%), chills (87.7%), and headache (66.8%). A community-based case-control study was carried out to investigate the risk factors of the scrub typhus outbreak. Bundling or moving waste straw (OR=9.0, 95%CI 4.6-17.8) and living at the edge of village (OR=0.6, 95%CI 0.4-0.9) posed the highest risks through single- and multi-variable conditional logistic regression. Phylogenetic analysis of the 56-kDa TSA gene showed that the new cluster (GB-C2) and the previously reported cluster (GB-C1) of O. tsutsugamushi were associated with this outbreak. These findings are useful for the establishment of a detailed control strategy for scrub typhus infection in previously unrecognized areas of Jiangsu Province, China.
authors.affiliation: Jiangsu Province Center for Disease Control and Prevention, Nanjing, China.
authors.forename: Jianli
authors.initials: J
authors.lastname: Hu
authors.affiliation: Jiangsu Province Center for Disease Control and Prevention, Nanjing, China.
authors.forename: Zhongming
authors.initials: Z
authors.lastname: Tan
authors.affiliation: Tongren Municipal Center for Disease Control and Prevention, Tongren, China.
authors.forename: Dafei
authors.initials: D
authors.lastname: Ren
authors.affiliation: Taizhou Municipal Center for Disease Control and Prevention, Taizhou, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Taizhou Municipal Center for Disease Control and Prevention, Taizhou, China.
authors.forename: Yilin
authors.initials: Y
authors.lastname: He
authors.affiliation: Jiangsu Province Center for Disease Control and Prevention, Nanjing, China.
authors.forename: Changjun
authors.initials: C
authors.lastname: Bao
authors.affiliation: Jiangsu Province Center for Disease Control and Prevention, Nanjing, China.
authors.forename: Dapeng
authors.initials: D
authors.lastname: Liu
authors.affiliation: Taizhou Municipal Center for Disease Control and Prevention, Taizhou, China.
authors.forename: Qianhua
authors.initials: Q
authors.lastname: Yi
authors.affiliation: Jingjiang County Center for Disease Control and Prevention, Jingjiang, China.
authors.forename: Weijuan
authors.initials: W
authors.lastname: Qian
authors.affiliation: Jingjiang County Center for Disease Control and Prevention, Jingjiang, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Yin
authors.affiliation: Jingjiang County Center for Disease Control and Prevention, Jingjiang, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Taizhou Municipal Center for Disease Control and Prevention, Taizhou, China.
authors.forename: Chunxia
authors.initials: C
authors.lastname: Yu
authors.affiliation: Jiangsu Province Center for Disease Control and Prevention, Nanjing, China.
authors.forename: Shenjiao
authors.initials: S
authors.lastname: Wang
authors.affiliation: Jiangsu Province Center for Disease Control and Prevention, Nanjing, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wu
authors.affiliation: Taizhou Municipal Center for Disease Control and Prevention, Taizhou, China.
authors.forename: Haiyu
authors.initials: H
authors.lastname: Yang
authors.affiliation: The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Yue
authors.affiliation: Huadong Research Institute for Medicine and Biotechnics, Nanjing, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Jiangsu Province Center for Disease Control and Prevention, Nanjing, China.
authors.forename: Wendong
authors.initials: W
authors.lastname: Liu
authors.affiliation: Jiangsu Province Center for Disease Control and Prevention, Nanjing, China.
authors.forename: Yefei
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Jiangsu Province Center for Disease Control and Prevention, Nanjing, China.
authors.forename: Minghao
authors.initials: M
authors.lastname: Zhou
authors.affiliation: Jiangsu Province Center for Disease Control and Prevention, Nanjing, China.
authors.forename: Fenyang
authors.initials: F
authors.lastname: Tang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D002648:Child; D002681:China / Q000453:epidemiology; D002947:Cities; D003710:Demography; D004196:Disease Outbreaks / Q000706:statistics & numerical data*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005843:Geography; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012307:Risk Factors; D012612:Scrub Typhus / Q000453:epidemiology*; D013997:Time Factors; D055815:Young Adult