BMC Infectious Diseases
Volume 12, 2012

Migrant tuberculosis: The extent of transmission in a low burden country (Article) (Open Access)

Kamper-Jørgensen Z.* , Andersen A.B. , Kok-Jensen A. , Kamper-Jørgensen M. , Bygbjerg I.C. , Andersen P.H. , Thomsen V.T. , Lillebaek T.
  • a International Reference Laboratory of Mycobacteriology, Statens Serum Institut, Copenhagen, Denmark, International Reference Laboratory of Mycobacteriology, Statens Serum Institut, 5 Orestads Boulevard, DK-2300 Copenhagen, Denmark
  • b Department of Infectious Diseases, Odense University Hospital, Odense, Denmark
  • c International Reference Laboratory of Mycobacteriology, Statens Serum Institut, Copenhagen, Denmark
  • d Department of Public Health, University of Copenhagen, Copenhagen, Denmark
  • e International Health Unit, Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark, Department of Infectious Diseases, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
  • f Department of Epidemiology, Statens Serum Institut, Copenhagen, Denmark
  • g International Reference Laboratory of Mycobacteriology, Statens Serum Institut, Copenhagen, Denmark
  • h International Reference Laboratory of Mycobacteriology, Statens Serum Institut, Copenhagen, Denmark, Department of Infectious Diseases, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark

Abstract

Background: Human migration caused by political unrest, wars and poverty is a major topic in international health. Infectious diseases like tuberculosis follow their host, with potential impact on both the migrants and the population in the recipient countries. In this study, we evaluate Mycobacterium tuberculosis transmission between the national population and migrants in Denmark.Methods: Register study based on IS6110-RFLP results from nationwide genotyping of tuberculosis cases during 1992 through 2004. Cases with 100% identical genotypes were defined as clustered and part of a transmission chain. Origin of clusters involving both Danes and migrants was defined as Danish/migrant/uncertain. Subsequently, the proportion of cases likely infected by the "opposite" ethnic group was estimated.Results: 4,631 cases were included, representing 99% of culture confirmed cases during 1992 through 2004. Migrants contributed 61.6% of cases. Up to 7.9% (95% CI 7.0-8.9) of migrants were infected by Danes. The corresponding figure was 5.8% (95% CI 4.8-7.0) for Danes. Thus, transmission from Danes to migrants occurred up to 2.5 (95% CI 1.8-3.5) times more frequent than vice versa (OR = 1). A dominant strain, Cluster-2, was almost exclusively found in Danes, particular younger-middle-aged males.Conclusions: Transmission between Danes and migrants is limited, and risk of being infected by the "opposite" ethnic group is highest for migrants. TB-control efforts should focus on continues micro-epidemics, e.g. with Cluster-2 in Danes, prevention of reactivation TB in high-risk migrants, and outbreaks in socially marginalized migrants, such as Somalis and Greenlanders. Fears that TB in migrants poses a threat for resident Danes seem exaggerated and unjustified. We believe this to be true for other low incidence countries as well. © 2012 Kamper-Jørgensen et al; licensee BioMed Central Ltd.

Author Keywords

Genotyping MOLECULAR EPIDEMIOLOGY Denmark IS6110-RFLP

Index Keywords

genetics genotype Polymorphism, Restriction Fragment Length bacterial transmission molecular epidemiology human middle aged Denmark controlled study Mycobacterium tuberculosis Aged geographic distribution nonhuman cluster analysis restriction fragment length polymorphism school child Humans classification Adolescent transposon male DNA Transposable Elements female Aged, 80 and over clinical evaluation tuberculosis Disease Transmission, Infectious high risk population prevalence isolation and purification Article disease transmission major clinical study adult migration infection risk molecular typing age distribution ethnicity Transients and Migrants bacterial strain bacterium culture Child
Link
https://www.scopus.com/inward/record.uri?eid=2-s2.0-84860492944&doi=10.1186%2f1471-2334-12-60&partnerID=40&md5=75f699455ac91bd9b687548ab8d5dfc9
DOI: 10.1186/1471-2334-12-60
ISSN: 14712334
Cited by: 57
Original Language: English