Tuberculosis transmission between foreign- and native-born populations in the EU/EEA: a systematic review

Abstract

Tuberculosis (TB) control programmes of many low TB incidence countries of the European Union/European Economic Area (EU/EEA) perceive challenges in controlling TB due to high numbers of TB in migrants from high-incidence countries.To assess the extent of TB transmission from the foreign-born to the native-born population, we quantitatively investigated the dynamics of TB transmission between these populations in the EU/EEA, using published molecular epidemiological studies. We searched PubMed and EMBASE databases from 1990 to August 2012.We identified 15 studies performed during 1992–2007 covering 12,366 cases, of which median (range) 49.2% (17.7%–86.4%) were foreign-born. The proportion of clustered isolates ranged between 8.5% and 49.1% of the total number of TB cases genotyped and among these, foreign-born cases were equally or more likely to have unique isolates compared to native-born cases. One third of the clusters were “mixed”, i.e. composed of foreign- and native-born cases, involving 0–34.2% of all genotyped cases. Cross-transmission among foreign and native populations was bidirectional, with wide differences across studies.This systematic review provides evidence that TB in a foreign-born population does not have a significant influence on TB in the native population in EU/EEA.

Tuberculosis Outbreak in an Educational Institution in Norway

“…Molecular epidemiology studies based on IS6110 restriction fragment length polymorphism (RFLP) indicated that during 1994 to 2005, on average, 2 nonimmigrants and 13 immigrants per year developed the disease as a result of infection within the country by imported Mycobacterium tuberculosis (Mtb) (2). Similar studies within the European Union/European Economic Area countries found that the TB incidence in a foreign-born population did not significantly affect the incidence of TB among the native population (2)(3)(4). However, these studies were based on RFLP, and the ability of this method to distinguish cases based on genetic homogeneity is limited.…”

Methodological and Clinical Aspects of the Molecular Epidemiology of Mycobacterium tuberculosis and Other Mycobacteria

“…In England, too, clusters often consisted of patients of multiple ethnicities and both homeless and nonhomeless populations (435). The aspect of transmission from immigrant to native populations in European Union/European Economic Area (EEA) countries was recently systematically reviewed (447). This review showed that the proportions of all studied TB cases that result from recent transmission within mixed (immigrant/native) clusters varied greatly between studies, from 0% to 34%; this proportion was Ͻ15% in 11 of the 15 studies analyzed (447).…”

“…The aspect of transmission from immigrant to native populations in European Union/European Economic Area (EEA) countries was recently systematically reviewed (447). This review showed that the proportions of all studied TB cases that result from recent transmission within mixed (immigrant/native) clusters varied greatly between studies, from 0% to 34%; this proportion was Ͻ15% in 11 of the 15 studies analyzed (447). However, in the European Union/EEA, foreign-born patients are less likely to belong to a cluster than are native-born patients, and those authors conclude that TB in foreign-born populations has no significant impact on TB in the native European Union/EEA population (447).…”

The Impact of Tuberculosis among Immigrants: Epidemiology and Strategies of Control in High-Income Countries—Current Data and Literature Review

“…The sensitivity and specificity of CXR vary from 86-97% to 75-89%, respectively, and according to the criteria of imaging interpretation. CXR alone does not detect extrapulmonary TB (EPTB) which is increasing in comparison to pulmonary TB, especially in low-burden and high immigrant receiving countries [26], and in HIV-positive persons that have higher rates of EPTB compared with those who are HIV-negative.…”