Mycobacterium tuberculosis genotypes in an ethnically diverse area with millions of pilgrims and thousands of immigrants.

Background: Immigration is considered as a risk factor of tuberculosis (TB). Qom province receives millions of pilgrims and significant numbers of immigrants each year. Most of the immigrants to Qom, arrive from neighboring TB-endemic countries. This study aimed to identify the current circulating Mycobacterium tuberculosis genotypes in Qom province using 24-locus MIRU-VNTR genotyping.
Methods: Eighty six M. tuberculosis isolates were collected during 2018-2022 from patients referring to Qom TB reference laboratory. The DNA of isolates was extracted and followed by 24 loci MIRU-VNTR genotyping which performed using the web tools available on MIRU-VNTRplus.
Results: Of 86 isolates, 39 (45.3%) were of Delhi/CAS genotype, 24 (27.9%) of NEW-1, 6 (7%) of LAM, 6 (7%) of Beijing, 2 (2.3%) of UgandaII, 2 (2.3%) of EAI, 1 of S (1.2%) and 6 (7%) did not match with profiles present in MIRUVNTRplus database.
Conclusions: About half of the isolates belong to Afghan immigrants; which warns health policy makers about the future situation of TB in Qom. Also, the similarity of Afghan and Iranian genotypes provides evidence that immigrants partake in the circulation of M. tuberculosis. This study underpin the studies about the circulating M. tuberculosis genotypes, their geographical distribution, the association of TB risk factors with these genotypes and the impact of immigration on the situation of TB in Qom province.
(© 2023. The Author(s).)