Evaluation and Molecular Comparison of Mycobacterium tuberculosis Strains Isolated from Iranian and Afghan Immigrants in Tehran

To determine tuberculosis transmission dynamics and relative contribution of infection acquired in Tehran and reactivation of tuberculosis infection acquired elsewhere in Afghan immigrants persons who developed tuberculosis in Tehran، and to determine the frequency of tuberculosis other person. The study population consisted of Afghan immigrants and Iranian tuberculosis patients reported in Tehran from 2008 to 2009. Restriction fragment length polymorphism (RFLP) typing was performed on Mycobacterium tuberculosis patient using IS6110 as a probe. Patients were assigned to clusters based on Mycobacterium isolated with identical DNA fingerprints. Clusters were assumed to have arisen from recent transmission. From 291 isolates، 60 were clustered in 25 clusters. (72%) contained 43 Iranian TB cases and (8%) had 4 Afghan patients. The remaining clusters، were contained both Iranian and Afghan TB cases. of the 60 Afghan immigrant patients studied، 5 (8. 4%) were clustered in 5 cluster and 55 (91. 6%) met the definition of reactivation of infection acquired elsewhere. During the studied period، reactivation of a previous infection remain the more probable cause of recurrence. 8. 4% of Afghan immigrants׳ patients who developed tuberculosis infection in Tehran، transmission from Afghan immigrants׳ patients leading to tuberculosis in other persons is uncommon.