Impact of immigration on the molecular epidemiology of Mycobacterium tuberculosis in a low-incidence country
Impact of immigration on the molecular epidemiology of Mycobacterium tuberculosis in a low-incidence country
复制标题
DOI：
10.1164/rccm.200702-187oc
复制
发表时间：
2007-11-01
影响因子：
24.7
通讯作者：
Heldal, Einar
中科院分区：
文献类型：
--
作者：
Dahle, Ulf R.;Eldholm, Vegard;Heldal, Einar
在许多低发病率国家，预防结核病发病率上升的规划受到来自高负担国家的国际旅行和移民的挑战。目的：目前的研究旨在确定1994-2005年整个国家人口中此类移民对结核分枝杆菌分离株遗传多样性的影响。方法：12年间共报告3131例结核病患者。其中，2284株（73%）经培养证实为结核，其中2173株（96%）经IS6110限制性片段长度多态性分析。测量结果和主要结果：纳入的菌株中只有31%来自非移民，其余69%来自移民。虽然发病率在这一时期有所增加，但遗传多样性仍然很高。共确定了135个群集；在研究期间，非移民中新近患病的比例有所下降，移民中保持稳定。虽然69%的分离株来自高发病率国家的移民，但接受国建立的结核病控制规划足以预防疾病传播。平均每年只有2名非移民和13名移民因在国内感染输入性结核分枝杆菌而患病。结论：结核分枝杆菌从高发国家移民入境12年，对该病原体在接收低发国家的传播影响不大。为防止今后结核病传播的增加，低发病率国家目前的控制战略是充分的，但必须予以维持。
Rationale Programs to prevent the incidence rate of tuberculosis (TB) from increasing in many low-incidence countries are challenged by international travel and immigration from high-burden countries.Objectives: The current study aimed to determine the effect of such immigration on the genetic diversity of Mycobacterium tuberculosis isolates in an entire nation's population during 1994-2005.Methods: A total of 3,131 patients were notified with TB during the 12-year period. Of these, 2,284 (73%) had TB verified by culture, and isolates from 2,173 (96%) of these were analyzed by IS6110 restriction fragment length polymorphism.Measurements and Main Results: Only 31% of the included strains were isolated from nonimmigrants, the remaining 69% were isolated from immigrants. Although the incidence increased throughout the period, the genetic diversity remained high. A total of 135 clusters were identified; the percentage of recent disease was reduced among nonimmigrants, and remained stable among the immigrants during the study period. Although 69% of the isolates originated from immigrants from high-incidence countries, the established TB control program in the receiving country was adequate for the prevention of disease transmission. On average per year, only 2 nonimmigrants and 13 immigrants developed disease as a result of infection within the country by imported M. tuberculosis.Conclusions: Twelve years of M. tuberculosis importation as a result of immigration from high-incidence countries had little influence on the transmission of this pathogen in the receiving low-incidence country. To prevent future increase of transmission of TB, the current control strategies of low-incidence countries are adequate but must be maintained.