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Background and Objective: Iran remains a major stronghold for glanders in the Middle East. In Iran, the non-indigenous Burkholderia mallei Razi 325 strain is used in manufacturing of the mallein, required for malleination of animals. Multi Locus Variable number tandem repeat analysis is currently the standard globally accepted genotyping system for Burkholderia mallei. This study was done to survey the genomic structure of Burkholderia mallei Razi 325, the strain used for industrial production of Mallein. Methods: In this descriptive study, a MLVA genotyping system with 4 previously-characterized loci VNTR140, VNTR1367, VNTR2065, VNTR2971 along with two new loci of VNTR24, VNTR41 was used. Results: Optimization of PCRs resulted in a single protocol that enabled simultaneous amplification of all the six loci. Sequencing of PCR products revealed there were 2, 3, 12, 6, 1 and 2 copies of the unit repeat hold in the genome of the Burkholderia mallei Razi 325 strain. This observation was extended to include the already-whole genome sequenced Chinese Burkholderia mallei ATCC 23344 and Burkholderia mallei BMQ and also Burkholderia mallei SAVP1 strains. Conclusion: The Burkholderia mallei Razi 325 strain is distinguishable from the other three strains through MLVA genotyping method.

Background and Objective: MIRU-VNTR typing is currently one of the most frequently-used standardized genotyping systems in molecular epidemiology of tuberculosis in the world. This sudy was done to determine the Mycobacterium tuberculosis genotyping by MIRU-VNTR method. Methods: This descriptive study was done on sputum, gastric lavage clinical specimens of 53 tuberculosis suspected patients. Fifty-three isolates were identified by 16S rRNA and Rv-typing followed by RD typing. They were then subjected to a 12-locus (ETRA, ETRB, ETRC, ETRD, ETRE and ETRF, MIRU-10, MIRU-26, MIRU-39, MIRU-30 plus QUB-11b) MIRU-VNTR typing system. Results: In MIRU-VNTR typing, forty-four types were identified with 13 isolates classified in 4 clustered and the remaining 40 isolates representing 40 orphan patterns. In comparative analysis of MIRU-VNTR loci, MIRU-26 with 7 alleles displayed the highest diversity level (Simpson’s diversity index = 0.767. Out of the 53 isolates, only one was identified as Mycobacterium bovis. All the remaining isolates were characterized as Mycobacterium tuberculosis. None of the samples was affected to Mycobacterium complex strain. No evidence of either double or co-infection of the patients with more than one species/strain was detected. Conclusion: While the genomic diversity observed by MIRU-VNTR typing sounds extensive, the population genomic structure on the whole however, seems to be homogenous. Recent transmission between studied patients does not appear to be a frequent event as only 13 isolates representing 4 MIRU-VNTR types, were assumingly epidemic.

Background and Objectives: Some 2 million tons of chicken meat is produced by Iran per annum, positioning Iran among the top producers in the region. This study aimed to evaluate the molecular epidemiology and genetic characteristics of Salmonella enterica Enteritidis in Iran. Materials and Methods: A representative selection of isolates (n=76), initially genotyped by a 7-locus MLVA typing system, was examined by the standard MLST genotyping. Results and Conclusion: All the MLVA typed isolates, classified into six types, were gathered under a single ST11 MLST type. This is an intriguing observation as much more genome heterogeneity was expected considering the extent of diversity in the host and geography origin of the examined isolates. ST11, on the other hand is not exclusively found in Iran as it is reported also from Brazil, Denmark, Japan and the United States. In explanation of these observations, ST11 might stand for a single probably ancestral clone of Salmonella enterica Enteritidis successfully scattered in all these geographically diverse countries. Further global investigation covering more isolates and methods like whole genome sequencing would be advisable.

Brucellosis is one of the most important zoonotic diseases and is a significant cause of abortion in animals. Brucella melitensis strain Rev. 1 is recommended as the most effective vaccine for small ruminants but the application of full doses in adult animals is restricted. This study was conducted to determine a proper reduced dose of vaccine which confers protection but which is not abortifacient in Iranian fat-tailed sheep. A total of 51 non-vaccinated pregnant ewes were divided into three main groups and several subgroups. Ewes in different groups were vaccinated at different stages of pregnancy and various subgroups were subcutaneously immunised with different quantities of the micro-organism (7.5 × 10(6), 10(6), 5 × 10(5)). Ewes again became pregnant a year later and were challenged with the wild-type strain to evaluate the protection conferred. Results revealed that the proportion of vaccination-induced abortions was significantly higher in ewes immunised with 7.5 × 10(6) Rev. 1 organisms than in those which received 10(6) or 5 × 10(5) bacteria. While 80% of non-vaccinated ewes aborted after challenge, none of the vaccinated ewes aborted post-challenge. This study indicated that a reduced dose of Rev. 1 vaccine containing 10(6) or 5 × 10(5) live cells could be safely used to induce protection in Iranian fat-tailed sheep at various stages of pregnancy.