Conventional and molecular epidemiology of Tuberculosis in Manitoba

BMC Infectious Diseases

Amin M Kabani²  Earl S Hershfield¹  Lawrence J Elliott⁴  Assaad Al-Azem⁴  Kym S Blackwood³ 

[1] Department of Medicine, University of Manitoba, Winnipeg, MB, Canada;Department of Clinical Microbiology, Health Sciences Center, Winnipeg, MB, Canada;National Reference Center for Mycobacteriology, National Microbiology Laboratory, Health, Canada, Winnipeg, MB, Canada;Department of Community Health Sciences, University of Manitoba, Winnipeg, MB, Canada

关键词: clustering;    DNA fingerprinting;    Mycobacterium tuberculosis;   

Others  :  1177120
DOI  :  10.1186/1471-2334-3-18

 received in 2003-06-11, accepted in 2003-08-13,  发布年份 2003

【 摘 要 】

Background

To describe the demographic and geographic distribution of tuberculosis (TB) in Manitoba, thus determining risk factors associated with clustering and higher incidence rates in distinct subpopulations.

Methods

Data from the Manitoba TB Registry was compiled to generate a database on 855 patients with tuberculosis and their contacts from 1992–1999. Recovered isolates of M. tuberculosis were typed by IS6110 restriction fragment length polymorphisms. Bivariate and multivariate logistic regression models were used to identify risk factors involved in clustering.

Results

A trend to clustering was observed among the Canadian-born treaty Aboriginal subgroup in contrast to the foreign-born. The dominant type, designated fingerprint type 1, accounts for 25.8% of total cases and 75.3% of treaty Aboriginal cases. Among type 1 patients residing in urban areas, 98.9% lived in Winnipeg. In rural areas, 92.8% lived on Aboriginal reserves. Statistical models revealed that significant risk factors for acquiring clustered tuberculosis are gender, age, ethnic origin and residence. Those at increased risk are: males (p < 0.05); those under age 65 (p < 0.01 for each age subgroup); treaty Aboriginals (p < 0.001), and those living on reserve land (p < 0.001).

Conclusion

Molecular typing of isolates in conjunction with contact tracing data supports the notion of the largest ongoing transmission of a single strain of TB within the treaty-status population of Canada recorded to date. This data demonstrates the necessity of continued surveillance of countries with low prevalence of the disease in order to determine and target high-risk populations for concentrated prevention and control measures.

【 授权许可】

   
2003 Blackwood et al; licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original URL.

【 图 表 】

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