Rubin Marcie S, Nivin Beth, Ackelsberg Joel
Department of Sociomedical Sciences, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA.
Clin Infect Dis. 2008 Jul 1;47(1):47-52. doi: 10.1086/588658.
Long-term care facilities (LTCFs) are vulnerable to outbreaks of influenza. There are limited data on the impact of antiviral chemoprophylaxis on the duration of outbreaks of influenza. We investigated the association of timely initiation of amantadine chemoprophylaxis on the duration and severity of outbreaks of influenza A in LTCFs in New York, New York.
Outbreaks of influenza A occurring from October through May each year during the period 2001-2004 in LTCFs in New York were defined as a single laboratory-confirmed case or a cluster of > or = 2 cases of influenza-like illness on a unit of an LTCF. For those facilities that provided amantadine chemoprophylaxis, we examined the association between the time to initiation of chemoprophylaxis after outbreak onset and duration of outbreak, incidence rate, and case-fatality proportion using simple t tests, multivariate analyses of covariance, and linear regression modeling.
Adjusting for influenza season year, facility bed capacity, and the proportion of residents who were vaccinated against influenza, LTCFs that initiated chemoprophylaxis 15 days after outbreak onset (25 facilities) had significantly longer duration of outbreaks (18.3 vs. 6.7 days; P < .001), higher incidence rates (10.5 cases per 100 residents vs. 6.2 cases per 100 residents; P < .023), and higher case-fatality rates (3.3 deaths per 100 residents with influenza A vs. 0.45 deaths per 100 residents with influenza A; P < .005) than did LTCFs that initiated chemoprophylaxis 5 days after outbreak onset (27 facilities).
LTCFs that initiated chemoprophylaxis >5 days after initiation of outbreaks of influenza A had significantly longer outbreaks, significantly higher incidence rates, and significantly higher case-fatality rates. These data support prompt initiation of amantadine chemoprophylaxis after identification of influenza A in LTCFs.
长期护理机构（LTCFs）易发生流感暴发。关于抗病毒化学预防对流感暴发持续时间的影响的数据有限。我们调查了在纽约市纽约州的长期护理机构中，及时开始金刚烷胺化学预防与甲型流感暴发的持续时间和严重程度之间的关联。
2001年至2004年期间，纽约市长期护理机构每年10月至次年5月发生的甲型流感暴发定义为单个实验室确诊病例或长期护理机构一个单元中≥2例类似流感疾病的聚集性病例。对于那些提供金刚烷胺化学预防的机构，我们使用简单t检验、多变量协方差分析和线性回归模型，研究了暴发开始后开始化学预防的时间与暴发持续时间、发病率和病死率之间的关联。
在调整流感季节年份、机构床位容量以及接种流感疫苗居民的比例后，暴发开始后15天开始化学预防的长期护理机构（25个机构）的暴发持续时间显著更长（18.3天对6.7天；P<.001），发病率更高（每100名居民10.5例对每100名居民6.2例；P<.023），病死率也更高（每100名甲型流感居民中有3.3例死亡对每100名甲型流感居民中有0.45例死亡；P<.005），而暴发开始后5天开始化学预防的长期护理机构（27个机构）则不然。
甲型流感暴发开始>5天后开始化学预防的长期护理机构的暴发持续时间显著更长，发病率显著更高，病死率也显著更高。这些数据支持在长期护理机构中识别出甲型流感后迅速开始金刚烷胺化学预防。
