Department of Virology, Haartman Institute, Helsinki, Finland.
J Infect Dis. 2011 Aug 1;204(3):459-66. doi: 10.1093/infdis/jir267.
Sindbis virus (SINV) is an arthropod-borne alphavirus that causes rash and arthritis. In Finland, epidemics occur cyclically, but factors associated with clinical SINV infection are largely unknown. We conducted a population-based case-control study during the epidemic year 2002.
SINV cases were serologically confirmed and reported to the National Infectious Disease Registry. Five control subjects, matched for age, sex, and residence, were selected from the National Population Information System. Data were collected using a self-administered mail survey. Conditional logistic regression models were used to identify independent risk factors; missing data were addressed using Bayesian full-likelihood modeling.
A total of 337 case patients (58% female; age range, 1-94 y) and 934 control subjects were enrolled. Reported exposure to mosquito bites (matched odds ratio [mOR], 16.7; 95% confidence interval [CI], 9.1-33.4) and spending time in woods or marshland (mOR, 1.8; 95% CI, 1.3-2.5) were independently associated with SINV infection in the multivariable model. The population-attributable risk for mosquito bites was 87.2%. There were dose-response relations for increased number of insect bites (mOR, 23.8-72.5) and increased time spent in woods or marshland (mOR, 1.3-2.2).
Educating the public in endemic areas to avoid mosquito exposure and use protective measures remain important prevention measures for SINV infection.
辛德毕斯病毒（SINV）是一种节肢动物传播的甲病毒，可引起皮疹和关节炎。在芬兰，该病呈周期性流行，但与临床 SINV 感染相关的因素在很大程度上尚不清楚。我们在 2002 年流行期间开展了一项基于人群的病例对照研究。
通过血清学确证 SINV 病例，并向国家传染病登记处报告。从国家人口信息系统中按照年龄、性别和居住地匹配选择 5 名对照。采用自填式邮件调查收集数据。使用条件逻辑回归模型确定独立的危险因素；采用贝叶斯完全似然建模处理缺失数据。
共纳入 337 例病例患者（58%为女性；年龄范围为 1-94 岁）和 934 名对照。报告的蚊虫叮咬暴露史（匹配比值比 [mOR]，16.7；95%置信区间 [CI]，9.1-33.4）和在树林或湿地中度过的时间（mOR，1.8；95%CI，1.3-2.5）与多变量模型中的 SINV 感染独立相关。蚊虫叮咬的人群归因风险为 87.2%。昆虫叮咬次数增加（mOR，23.8-72.5）和在树林或湿地中度过的时间增加（mOR，1.3-2.2）与感染风险呈剂量-反应关系。
在流行地区，向公众宣传避免蚊虫暴露和采取保护措施仍然是预防 SINV 感染的重要措施。
