Background: As regards multilocus sequence typing (MLST) method directly analyze the polymorphism within DNA sequences; we performed the first nationwide study on the genotypic relationships of Candida albicans strains obtained from oropharynx and bronchoalveolar lavage (BAL) samples from immunocompromised patients.Methods: Fourteen epidemiologically unrelated clinical strains of C. albicans were obtained from three hospitals in Ma-zandaran Province, Iran (2006 to 2012) from seven patients with pulmonary infections and the rest with oropharyngeal samples of immunocompromised patients. Seven loci of housekeeping genes were sequenced for all fourteen isolates.Results: MLST was applied to a subset of 14 unrelated isolates. Seventy-one (2.5%) nucleotide sites were found to be variable. Accordingly, 60 different alleles were identified in seven loci among the isolates, among which two new alleles were obtained. Furthermore, 12 independent diploid sequence types (DSTs) including five novel DSTs were identified. The fourteen unrelated isolates were placed in 10 clonal clusters (CC) while two isolates were singletons, by eBURST analysis. Most of the isolates belonged to CC461 of eBURST analysis from the clade 11 and two isolates assigned to CC172 from the clade 15.Conclusion: Pathogen distribution and relatedness for determining the epidemiology of nosocomial infections is highly recommended for pathogen control methods.

Background: Vibrio cholerae is an important bacterium causing profuse watery diarrhea. Cholera had swept the whole Shandong province from 1975 to 2013. Methods: From epidemiological data and pulsed-field gel electrophoresis data, we selected 86 V. cholerae isolates appearing in Shandong Province in China from 1975 to 2013 and characterized them by multilocus sequence typing (MLST)/multi-virulence locus sequence typing (MVLST), antibiogram and analysis of genes related to antibiotic resistance. Results: Combined MLST/MVLST data revealed 33 sequence types and a major group. Within the group, 3 subgroups (ST1, ST24 and ST29) were revealed, prevalent in the strains isolated during the 1980s, 1990s and 21st century, respectively. All the O1 isolates after 1990 were found to be El Tor variants harboring the classical ctxB gene. The tcpA gene of O139 strains had a mutation at amino acid position 62 (N→ D). Antibiotic re-sistance of V. cholerae increased over time. Most El Tor variants between 1998 and 1999 were resistant to trime-thoprim/sulfamethoxazole. The O139 strain, since its appearance in 1997, had significantly broader spectrum of antibiotic resistance than O1 variants. The presence of the SXT element corresponds to the trend of growing drug resistance. Conclusion: The analysis of genotypic polymorphism and enhanced resistance of V. cholerae indicated continuous variation and evolution of this pathogenic agent in Shandong Province.

Background and Objectives: Some 2 million tons of chicken meat is produced by Iran per annum, positioning Iran amongthe top producers in the region. This study aimed to evaluate the molecular epidemiology and genetic characteristics of Salmonellaenterica 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 MLSTtype. This is an intriguing observation as much more genome heterogeneity was expected considering the extent of diversityin the host and geography origin of the examined isolates. ST11, on the other hand is not exclusively found in Iran as it isreported also from Brazil, Denmark, Japan and the United States. In explanation of these observations, ST11 might standfor a single probably ancestral clone of Salmonella enterica Enteritidis successfully scattered in all these geographicallydiverse countries. Further global investigation covering more isolates and methods like whole genome sequencing would beadvisable.