Greenbaum Adena, Quinn Celia, Bailer Jennifer, Su Su, Havers Fiona, Durand Lizette O, Jiang Victoria, Page Shannon, Budd Jeremy, Shaw Michael, Biggerstaff Matthew, de Fijter Sietske, Smith Kathleen, Reed Carrie, Epperson Scott, Brammer Lynnette, Feltz Dave, Sohner Kevin, Ford Jared, Jain Seema, Gargiullo Paul, Weiss Edward, Burg Pat, DiOrio Mary, Fowler Brian, Finelli Lyn, Jhung Michael A
Epidemic Intelligence Service Influenza Division.
Epidemic Intelligence Service Ohio Department of Health, Columbus.
J Infect Dis. 2015 Nov 15;212(10):1592-9. doi: 10.1093/infdis/jiv269. Epub 2015 May 5.
In 2012, one third of cases in a multistate outbreak of variant influenza A(H3N2) virus ([H3N2]v) infection occurred in Ohio. We conducted an investigation of (H3N2)v cases associated with agricultural Fair A in Ohio.
We surveyed Fair A swine exhibitors and their household members. Confirmed cases had influenza-like illness (ILI) and a positive laboratory test for (H3N2)v, and probable cases had ILI. We calculated attack rates. We determined risk factors for infection, using multivariable log-binomial regression.
We identified 20 confirmed and 94 probable cases associated with Fair A. Among 114 cases, the median age was 10 years, there were no hospitalizations or deaths, and 82% had swine exposure. In the exhibitor household cohort of 359 persons (83 households), we identified 6 confirmed cases (2%) and 40 probable cases (11%). An age of <10 years was a significant risk factor (P < .01) for illness. One instance of likely human-to-human transmission was identified.
In this (H3N2)v outbreak, no evidence of sustained human-to-human (H3N2)v transmission was found. Our risk factor analysis contributed to the development of the recommendation that people at increased risk of influenza-associated complications, including children aged <5 years, avoid swine barns at fairs during the 2012 fair season.
2012年，甲型H3N2变异病毒（[H3N2]v）感染的多州疫情中有三分之一的病例发生在俄亥俄州。我们对俄亥俄州与A农业展会相关的（H3N2）v病例进行了调查。
我们对A展会的猪参展商及其家庭成员进行了调查。确诊病例有流感样疾病（ILI）且（H3N2）v实验室检测呈阳性，疑似病例有ILI。我们计算了发病率。我们使用多变量对数二项回归确定感染的危险因素。
我们确定了与A展会相关的20例确诊病例和94例疑似病例。在114例病例中，年龄中位数为10岁，无住院或死亡病例，82%有猪接触史。在359人（83户）的参展商家庭队列中，我们确定了6例确诊病例（2%）和40例疑似病例（11%）。年龄<10岁是患病的一个重要危险因素（P <.01）。发现了一例可能的人传人情况。
在此次（H3N2）v疫情中，未发现（H3N2）v持续人传人的证据。我们的危险因素分析有助于提出以下建议：包括<5岁儿童在内的流感相关并发症风险增加的人群，在2012年展会季节期间应避免进入展会的猪舍。
