The present update on the global distribution of Mycobacterium tuberculosis complex spoligotypes provides both the octal and binary descriptions of the spoligotypes for M. tuberculosis complex, including Mycobacterium bovis, from >90 countries (13,008 patterns grouped into 813 shared types containing 11,708 isolates and 1,300 orphan patterns). A number of potential indices were developed to summarize the information on the biogeographical specificity of a given shared type, as well as its geographical spreading (matching code and spreading index, respectively). To facilitate the analysis of hundreds of spoligotypes each made up of a binary succession of 43 bits of information, a number of major and minor visual rules were also defined. A total of six major rules (A to F) with the precise description of the extra missing spacers (minor rules) were used to define 36 major clades (or families) of M. tuberculosis. Some major clades identified were the East African-Indian (EAI) clade, the Beijing clade, the Haarlem clade, the Latin American and Mediterranean (LAM) clade, the Central Asian (CAS) clade, a European clade of IS6110 low banders (X; highly prevalent in the United States and United

We present a short summary of recent observations on the global distribution of the major clades of the Mycobacterium tuberculosis complex, the causative agent of tuberculosis. This global distribution was defined by data-mining of an international spoligotyping database, SpolDB3. This database contains 11,708 patterns from as many clinical isolates originating from more than 90 countries. The 11,708 spoligotypes were clustered into 813 shared types. A total of 1,300 orphan patterns (clinical isolates showing a unique spoligotype) were also detected.

No abstract

The genetic diversity of Mycobacterium tuberculosis isolates among patients from Sweden was determined by a combination of two PCR-based techniques (spoligotyping and variable number of tandem repeats analysis). It resulted in a clustering of 23.6% of the isolates and a rate of recent transmission of 14.1%. The clustered isolates mainly belonged to the Haarlem family (23.2%), followed by the Beijing (9.8%), Latin American and Mediterranean (LAM; 8%), and East African-Indian (EAI; 6.2%) families. A comparison of the spoligotypes with those in the international spoligotyping database showed that 62.5% of the clustered isolates and 36.6% of all isolates typed were grouped into six major shared types. A comparison of the spoligotypes with those in databases for Scandinavian countries showed that 33% of the isolates belonged to an ill-defined T family, followed by the EAI (22%), Haarlem (20%), LAM (11%), Central Asian (5%), X (5%), and Beijing (4%) families. Both the highest number of cases and the proportion of clustered cases were observed in patients ages 15 to 39 years. Nearly 10% of the isolates were resistant to one or more drugs (essentially limited to isoniazid monoresistance). However, none of the strains were multidrug resistant. Data on the geographic origins of the patients showed that more than two-thirds of the clustered patients with tuberculosis were foreign-born individuals or refugees. These results are explained on the basis of both the historical links within specific countries and recently imported cases of tuberculosis into Sweden.