JCM Figure table search 04
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Dahle, U. R.
Right arrow Articles by Caugant, D. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Dahle, U. R.
Right arrow Articles by Caugant, D. A.

 Previous Article  |  Next Article 

Journal of Clinical Microbiology, May 2001, p. 1802-1807, Vol. 39, No. 5
0095-1137/01/$04.00+0   DOI: 10.1128/JCM.39.5.1802-1807.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.

Molecular Epidemiology of Mycobacterium tuberculosis in Norway

Ulf R. Dahle,1 Per Sandven,1 Einar Heldal,2 and Dominique A. Caugant1,*

Department of Bacteriology, National Institute of Public Health, N-0403 Oslo,1 and National Health Screening Service, N-0033 Oslo,2 Norway

Received 2 January 2001/Returned for modification 17 February 2001/Accepted 4 March 2001

The incidence of tuberculosis in Norway is one of the lowest in the world, and approximately half of the cases occur in first- and second-generation immigrants. In the present study, the genetic diversity of 92% of all strains of Mycobacterium tuberculosis isolated in Norway in 1994 to 1998 was assessed using restriction fragment length polymorphism (RFLP) analysis, with the insertion sequence IS6110 and the repetitive element DR as probes, to determine the degree of active transmission between patients. The DR probe was used as a secondary molecular marker to support or rule out clustering of strains with fewer than five copies of IS6110. After exclusion of 20 cultures representing laboratory contamination, 573 different IS6110 patterns were found among the 698 strains analyzed. Of these 573 patterns, 542 were observed only once and 31 were shared by 2 to 14 isolates. Among 81 strains (11.5%) carrying fewer than five copies of IS6110, 56 RFLP patterns were found when the results of both the IS6110 and DR methods were combined. Among the 698 strains, 570 were considered to be independent cases. A total of 14.5% of the native Norwegians and 19.7% of the foreign patients were part of a cluster. Thus, the degree of recent transmission of tuberculosis in Norway is low and the great majority of the cases are due to reactivation of previous disease. Transmission between immigrants and native Norwegians is uncommon. Two outbreaks, one among native Norwegians and one mainly among immigrants, have been ongoing for several years, indicating that, even in a low-incidence country such as Norway, with a good national program for tuberculosis surveillance, certain transmission chains are difficult to break.

* Corresponding author. Mailing address: Department of Bacteriology, National Institute of Public Health, P.O. Box 4404 Nydalen, N-0403 Oslo, Norway. Phone: (47) 22 04 23 11. Fax: (47) 22 04 25 18. E-mail: dominique.caugant{at}folkehelsa.no.

Journal of Clinical Microbiology, May 2001, p. 1802-1807, Vol. 39, No. 5
0095-1137/01/$04.00+0   DOI: 10.1128/JCM.39.5.1802-1807.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Antimicrob. Agents Chemother. Clin. Microbiol. Rev.
Clin. Vaccine Immunol. ALL ASM JOURNALS

Copyright © 2001 by the American Society for Microbiology. All rights reserved.