van Aart C, Boshuizen H, Dekkers A, Korthals Altes H
Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven.
Department for Statistics, Informatics and Modeling, National Institute for Public Health and the Environment, Bilthoven, The Netherlands.
Int J Tuberc Lung Dis. 2017 May 1;21(5):486-492. doi: 10.5588/ijtld.16.0548.
In low-incidence countries, most tuberculosis (TB) cases are foreign-born. We explored the temporal relationship between immigration and TB in first-generation immigrants between 1995 and 2012 to assess whether immigration can be a predictor for TB in immigrants from high-incidence countries.
We obtained monthly data on immigrant TB cases and immigration for the three countries of origin most frequently represented among TB cases in the Netherlands: Morocco, Somalia and Turkey. The best-fit seasonal autoregressive integrated moving average (SARIMA) model to the immigration time-series was used to prewhiten the TB time series. The cross-correlation function (CCF) was then computed on the residual time series to detect time lags between immigration and TB rates.
We identified a 17-month lag between Somali immigration and Somali immigrant TB cases, but no time lag for immigrants from Morocco and Turkey.
The absence of a lag in the Moroccan and Turkish population may be attributed to the relatively low TB prevalence in the countries of origin and an increased likelihood of reactivation TB in an ageing immigrant population. Understanding the time lag between Somali immigration and TB disease would benefit from a closer epidemiological analysis of cohorts of Somali cases diagnosed within the first years after entry.
在低发病率国家，大多数结核病（TB）病例是外国出生的。我们探讨了1995年至2012年间第一代移民中移民与结核病之间的时间关系，以评估移民是否可作为高发病率国家移民患结核病的预测因素。
我们获取了荷兰结核病病例中最常见的三个原籍国（摩洛哥、索马里和土耳其）的移民结核病病例和移民情况的月度数据。对移民时间序列采用最佳拟合季节性自回归积分滑动平均（SARIMA）模型对结核病时间序列进行预白化处理。然后对残差时间序列计算互相关函数（CCF），以检测移民与结核病发病率之间的时间滞后。
我们发现索马里移民与索马里移民结核病病例之间存在17个月的滞后，但摩洛哥和土耳其移民不存在时间滞后。
摩洛哥和土耳其人群中不存在滞后现象可能归因于原籍国相对较低的结核病患病率以及老龄移民人群中结核病复发可能性增加。对入境后头几年内确诊的索马里病例队列进行更密切的流行病学分析，将有助于了解索马里移民与结核病发病之间的时间滞后。
