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Brucellosis is an endemic infection in Iran and represents a serious health problem in humans and livestock causing important economic losses. The objective of this study was to undertake molecular characterization of Brucella spp. isolated from humans and livestock in several provinces of Iran including by multi-locus sequence typing (MLST), in order to understand the genotypes circulating in Iran and their relationship to genotypes globally. A total of 23 Brucella isolates were isolated from eight milk samples (seven cows, and one camel), human blood samples (seven), bovine lymph nodes (two), and samples from aborted fetuses (three sheep, two cows, and one goat). Phenotypic and molecular identification of Brucella isolates was performed on all isolated bacteria and showed that all were either Brucella melitensis or Brucella abortus. B. melitensis was associated with ovine/caprine and camel samples, most human isolates, and a significant minority of cattle isolates. In contrast B. abortus from livestock was associated only with isolations from bovine samples, as well as a single human sample. These results indicate that both B. melitensis and B. abortus contribute to the human brucellosis burden in Iran. B. melitensis isolates comprised three MLST-9 genotypes, the common and globally distributed ST8, a single representative of ST7, and several additional examples of ST102, a genotype previously only reported in a single isolate from a human brucellosis case believed to be acquired through travel to Iran. B. abortus isolates represented two globally common MLST-9 genotypes (ST1 and ST2), with relationships to biotype and other PCR-based typing methods consistent with previous observations. The results provide the basis for further studies examining the molecular epidemiology of Brucella circulating in Iran and the relationships of local isolates to those present globally., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Brucellosis is an endemic zoonosis in sub-Saharan Africa. Pastoralists are at high risk of infection but data on brucellosis from these communities are scarce. The study objectives were to: estimate the prevalence of human brucellosis, identify the Brucella spp. causing illness, describe non-Brucella bloodstream infections, and identify risk factors for brucellosis in febrile patients from a pastoralist community of Tanzania. Fourteen (6.1%) of 230 participants enrolled between August 2016 and October 2017 met study criteria for confirmed (febrile illness and culture positivity or ≥four-fold rise in SAT titre) or probable (febrile illness and single SAT titre ≥160) brucellosis. Brucella spp. was the most common bloodstream infection, with B. melitensis isolated from seven participants and B. abortus from one. Enterococcus spp., Escherichia coli, Salmonella enterica, Staphylococcus aureus and Streptococcus pneumoniae were also isolated. Risk factors identified for brucellosis included age and herding, with a greater probability of brucellosis in individuals with lower age and who herded cattle, sheep or goats in the previous 12 months. Disease prevention activities targeting young herders have potential to reduce the impacts of human brucellosis in Tanzania. Livestock vaccination strategies for the region should include both B. melitensis and B. abortus.

The potentially debilitating zoonotic disease brucellosis is thought to have been a scourge of mankind throughout history. New work by Kay et al. [mBio 5(4):e01337-14, 2014] adds to evidence for this by exploiting the huge advances in next-generation sequencing technology and applying shotgun metagenomics to a calcified nodule obtained from a 14th-century skeleton from Sardinia. While not the first DNA-based confirmation of Brucella in medieval DNA samples, Kay et al.'s study goes much further than previous reports based on single gene fragments in that it allows a full-genome reconstruction and thus facilitates meaningful comparative analysis of relationships with extant Brucella strains. These analyses confirm the close relationship of the genome to contemporary isolates from the western Mediterranean, illustrating the continuity of this lineage in the region over centuries. The study, along with recent studies characterizing other ancient-pathogen genomes, confirms that shotgun metagenomics offers us a powerful tool to fully characterize pathogens from ancient samples. Such studies promise to revolutionize our understanding of the nature of infectious disease in these materials and of the wider picture of the emergence, evolution, and spread of bacterial pathogens over history., (Copyright © 2014 Crown.)

Consumption of inadequately pasteurized dairy products is the most common means of transmission of brucellosis. This report describes two foodborne outbreaks that occurred in families infected after consumption of fresh home-made cheese bought in different Argentine provinces. High resolution variable number of tandem repeats (VNTR)-based analysis revealed two well-defined groups comprising essentially identical profiles and corresponding to the two different outbreaks. Similar clinical findings in members of the same family could indicate that the differential virulence of different bacterial clones, as indicated by VNTR data, could have influenced the course of the disease. We observed the importance of adequate treatment in early stages of the disease; combination therapy and extended treatment for 6 weeks or longer yielded significantly better results. The risk of the foodborne transmission of this zoonotic disease and disease prevention should be considered.

The bacteria of the Brucella genus are responsible for a worldwide zoonosis called brucellosis. They belong to the alpha-proteobacteria group, as many other bacteria that live in close association with a eukaryotic host. Importantly, the Brucellae are mainly intracellular pathogens, and the molecular mechanisms of their virulence are still poorly understood. Using the complete genome sequence of Brucella melitensis, we generated a database of protein-coding open reading frames (ORFs) and constructed an ORFeome library of 3091 Gateway Entry clones, each containing a defined ORF. This first version of the Brucella ORFeome (v1.1) provides the coding sequences in a user-friendly format amenable to high-throughput functional genomic and proteomic experiments, as the ORFs are conveniently transferable from the Entry clones to various Expression vectors by recombinational cloning. The cloning of the Brucella ORFeome v1.1 should help to provide a better understanding of the molecular mechanisms of virulence, including the identification of bacterial protein-protein interactions, but also interactions between bacterial effectors and their host's targets.

This study aimed at molecular detection and characterization of Brucella spp from Pakistan. For this purpose, whole blood samples (n=167) were collected from different species of livestock and analysed at Animal and Plant Health Agency (APHA), United Kingdom. Samples were analysed employing Rose Bengal Test (RBT), Competitive Enzyme-linked immunosorbent assay (cELISA), PCR IS711 and culture examination. We found 1% (2/167) samples positive for infection by culture, 4% (7/167) by RBT, 6% (10/167) by cELISA and 21% (35/167) by PCR IS711. Results were found statistically significant using chi-square test (p-value <0.05). The blood culture positive bacterial isolations were further subjected to classical biotyping and molecular techniques for characterization and found as non-vaccine strains of Brucella melitensis. Molecular characterization using Multilocus Sequence Analysis (MLSA) and Variable Number of Tandem Repeat (VNTR) analysis demonstrated that although there was some similarity in the patterns generated, the isolations were distinct from each other. These isolates were not the part of geographically confined group but were representative of other B. melitensis strains found in the region stretching from southern Europe into South Asia. To our knowledge, this is the first report of molecular characterization of B. melitensis isolates from Pakistan. The molecular methods described in the present study will help to understand the disease dynamics and future brucellosis control in Pakistan. [ABSTRACT FROM AUTHOR]