Prevalence of Haarlem I and Beijing types of Mycobacterium tuberculosis strains in Iranian and Afghan MDR-TB patients

Abstract

This survey identified the spoligopatterns of Mycobacterium tuberculosis strains with an international designation responsible for transmission and prevalence of Multi-Drug Resistance Tuberculosis (MDR-TB) among native and immigrant population of Tehran (2000-2005). The spacer oligonucleotides typing was performed on 263 M. tuberculosis strains isolated from verified cases of MDR-TB. Clinical and demographical data of patients were collected using traditional methods. Classical epidemiological investigation revealed that out of 263 MDR-TB cases, 175, 66.5% were isolated from Afghan immigrants. In both communities, majority of MDR-TB cases had either previous history of TB (107, 40.6%) or had a close contact (84, 31.9%). By spoligotyping, 27 distinct patterns were observed, 253 clinical isolates were grouped in 17 clusters (62.9%) and 10 isolates displayed an orphan pattern (37%). Based on an international spoligotype database, Haarlem I (85, 33.5%), Beijing (52, 20.5%), Central Asia (32, 12.1%), and EAI (21, 8.3%) were the major identified super families. Although, 76.9% of the Beijing genotypes and 100% of ST(253) strains (that was prevalent through former Soviet Union) were isolated from Afghan patients only. The linkage patterns between 30 Iranian and Afghan patients were observed. The study highlighted the epidemic potential of Haarlem I and Beijing genotypes among MDR-TB cases in Tehran territory.