Tuberculosis due to Resistant Haarlem Strain, Tunisia

Abstract

Multidrug-resistant tuberculosis was diagnosed in 21 HIV-negative, nonhospitalized male patients residing in northern Tunisia. A detailed investigation showed accelerated transmission of a Mycobacterium tuberculosis clone of the Haarlem type in 90% of all patients. This finding highlights the epidemic potential of this prevalent genotype.

Genetic profiling of Mycobacterium tuberculosis in Tunisia: predominance and evidence for the establishment of a few genotypes

“…We have previously conducted a molecular epidemiological investigation in the extreme north of Tunisia (Bizerte) and described an MDR-TB outbreak due to an ST50-Haarlem3 M. tuberculosis strain endowed with an increased transmissibility potential (Mardassi et al, 2005). In this study, we extended our analysis to two neighbouring regions and provide a detailed picture of the current TB epidemiology in Tunisia.…”

“…With regard to drug resistance, we have not been able to identify any clustering with the exception of the ST50 MDR outbreak (Mardassi et al, 2005). This certainly reflects the success of the five components of the DOTS strategy, the application of which has reached 100 % coverage rate.…”

“…Shading indicates clusters of isolates from the same geographical region, which, according to the epidemiological data, are likely to represent true transmission chains. The largest cluster associated with ST50 represents the previously described Haarlem3 MDR outbreak (Mardassi et al, 2005). also been reported in Central America, Europe and South America (Brudey et al, 2006).…”

“…The clustering rates for ST50 and ST42 genotypes were estimated to be 62.3 and 18.64 %, respectively. The largest cluster of the ST50-Haarlem3 genotype included 26 cases involved in a previously described severe multidrug-resistant (MDR) outbreak (Mardassi et al, 2005), which, at the time of writing, has involved a total of 32 patients. If these 26 outbreak-associated cases were excluded from the analysis, the clustering rate for the ST50 genotype dropped to 49.3 %.…”

Pulmonary Tuberculosis and Mycobacterium Tuberculosis: Modern Molecular Epidemiology and Perspectives

“…They identified various infectious chains of contact that, starting in a bar that played the role of a turntable, moved out rapidly into several areas such as housing for homeless men and alcoholics and a tank-cleaning firm.This study can be considered as a model because it combines detailed clinical and epidemiological data and phenotypical and molecular studies. Nowadays, numerous outbreaks continue to be identified in various public areas such as hospitals, schools, bars, prisons, nursing homes, and homeless shelters in developed and developing countries [38,52,90,92,105,116,120,153,159,178]. These studies were also able to identify risk factors for TB transmission.…”