Open AccessRisk Factors for Bunyavirus-Associated Severe Fever with Thrombocytopenia Syndrome: A Community-Based Case-Control Study
Author(s) -
Jianli Hu,
Zhifeng Li,
Xiaochen Wang,
Lei Hong,
Huaqiang He,
Weiguo Chen,
Lu-xun Li,
Ai-hua Shen,
Xuejian Liu,
Shou-guo Yuan,
Jiangang Zhou,
Winston Tan,
Wei-Zhong Zhou,
Fenyang Tang,
Fanxiu Zhu,
Changjun Bao
Publication year - 2016
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0166611
Subject(s) - severe fever with thrombocytopenia syndrome , medicine , phlebovirus , tick , case control study , demographics , multivariate analysis , emerging infectious disease , immunology , disease , demography , virology , bunyaviridae , virus , sociology
Background Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by a novel bunyavirus. Previous studies about risk factors for SFTSV infection have yielded inconsistent results, and behavior factors have not been fully clarified. Methods A community-based, 1:4 matched case-control study was carried out to investigate the risk factors for SFTS in China. Cases of SFTS were defined as laboratory-confirmed cases that tested positive for real-time PCR (RT-PCR) for severe fever with thrombocytopenia syndrome bunyavirus (SFTSV) or positive for IgM antibodies against SFTSV. Controls of four neighborhood subjects were selected by matching for sex, age, and occupation. Standardized questionnaires were used to collect detailed information about their demographics and risk factors for SFTSV infection. Results A total of 334 subjects participated in the study including 69 cases and 265 controls. The median age of the cases was 59.5 years, 55.1% were male, and 87.0% were farmers. No differences in demographics were observed between cases and controls. In the final multivariate analysis, tick bites two weeks prior to disease onset (OR = 8.04, 95%CI 3.34–19.37) and the presence of weeds and shrubs around the house (OR = 3.46, 95%CI 0.96–12.46) were found to be risk factors for SFTSV infection; taking preventative measures during outdoor activities (OR = 0.12, 95%CI 0.01–1.01) provided greater protection from SFTSV infection. Conclusions Our results further confirm that SFTSV is transmitted by tick bites and prove that preventative measures that reduce exposure to ticks can prevent SFTSV infection. More efforts should be directed toward health education and behavior change for high-risk populations, especially outdoor workers, in SFTS endemic areas.