Zoonotic tuberculosis caused by Mycobacterium bovis, Central province, Iran

Abstract

Background and objectives: Although Mycobacterium tuberculosis (M. tuberculosis) causes most cases of human tuberculosis (TB), Mycobacterium bovis (M. bovis) is an important cause of TB infections in certain populations. Identification of M. bovis as a member of M. tuberculosis complex could be valuable in term of public health control measures. In search for cases of zoonotic TB we have performed an 18-month molecular epidemiology study on all patients presenting pulmonary tuberculosis admitted to public hospitals in Markazi province, central Iran. Materials and methods: Only one Mycobacterium bovis isolate was detected among 42M. tuberculosis isolates that were successfully collected during the research. Identified as M. bovis by phenotypic tests, PCR-RFLP for OxyR gene of this isolate coupled with findings of PGRS-RFLP and also DR-RFLP genotyping demonstrated an entirely different strain to those previously reported from animal hosts in Iran. Results: Considering the very homogenous population of M. bovis in Iran, and the patient’s age, 75, we assume this isolate displays activation of an earlier exposure to M. bovis during the patient’s life. Conclusion: Besides, our data suggest a low contribution of M. bovis in human TB in the region and possibly in the whole country.