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Clinical Microbiology Reviews Dec 2019The clinical presentation of brucellosis in humans is variable and unspecific, and thus, laboratory corroboration of the diagnosis is essential for the patient's proper... (Review)
Review
The clinical presentation of brucellosis in humans is variable and unspecific, and thus, laboratory corroboration of the diagnosis is essential for the patient's proper treatment. The diagnosis of brucellar infections can be made by culture, serological tests, and nucleic acid amplification assays. Modern automated blood culture systems enable detection of acute cases of brucellosis within the routine 5- to 7-day incubation protocol employed in clinical microbiology laboratories, although a longer incubation and performance of blind subcultures may be needed for protracted cases. Serological tests, though they lack specificity and provide results that may be difficult to interpret in individuals repeatedly exposed to organisms, nevertheless remain a diagnostic cornerstone in resource-poor countries. Nucleic acid amplification assays combine exquisite sensitivity, specificity, and safety and enable rapid diagnosis of the disease. However, long-term persistence of positive molecular test results in patients that have apparently fully recovered is common and has unclear clinical significance and therapeutic implications. Therefore, as long as there are no sufficiently validated commercial tests or studies that demonstrate an adequate interlaboratory reproducibility of the different homemade PCR assays, cultures and serological methods will remain the primary tools for the diagnosis and posttherapeutic follow-up of human brucellosis.
Topics: Brucella; Brucellosis; Clinical Laboratory Techniques; Humans; Molecular Diagnostic Techniques; Nucleic Acid Amplification Techniques; Serologic Tests
PubMed: 31722888
DOI: 10.1128/CMR.00073-19 -
International Journal of Molecular... Oct 2020organisms are responsible for one of the most widespread bacterial zoonoses, named brucellosis. The disease affects several species of animals, including humans. One of... (Review)
Review
organisms are responsible for one of the most widespread bacterial zoonoses, named brucellosis. The disease affects several species of animals, including humans. One of the most intriguing aspects of the brucellae is that the various species show a ~97% similarity at the genome level. Still, the distinct species display different host preferences, zoonotic risk, and virulence. After 133 years of research, there are many aspects of the biology that remain poorly understood, such as host adaptation and virulence mechanisms. A strategy to understand these characteristics focuses on the relationship between the genomic diversity and host preference of the various species. Pseudogenization, genome reduction, single nucleotide polymorphism variation, number of tandem repeats, and mobile genetic elements are unveiled markers for host adaptation and virulence. Understanding the mechanisms of genome variability in the genus is relevant to comprehend the emergence of pathogens.
Topics: Animals; Brucella; Brucellosis; Evolution, Molecular; Genome, Bacterial; Genomics; Humans; Phylogeny; Polymorphism, Single Nucleotide; Virulence
PubMed: 33092044
DOI: 10.3390/ijms21207749 -
Journal of Clinical Microbiology Aug 2023Bacteria of the genus Brucella are facultative intracellular parasites that cause brucellosis, a severe animal and human disease. Recently, a group of taxonomists merged...
Bacteria of the genus Brucella are facultative intracellular parasites that cause brucellosis, a severe animal and human disease. Recently, a group of taxonomists merged the brucellae with the primarily free-living, phylogenetically related spp. in the genus Brucella. This change, founded only on global genomic analysis and the fortuitous isolation of some opportunistic spp. from medically compromised patients, has been automatically included in culture collections and databases. We argue that clinical and environmental microbiologists should not accept this nomenclature, and we advise against its use because (i) it was presented without in-depth phylogenetic analyses and did not consider alternative taxonomic solutions; (ii) it was launched without the input of experts in brucellosis or ; (iii) it applies a non-consensus genus concept that disregards taxonomically relevant differences in structure, physiology, population structure, core-pangenome assemblies, genome structure, genomic traits, clinical features, treatment, prevention, diagnosis, genus description rules, and, above all, pathogenicity; and (iv) placing these two bacterial groups in the same genus creates risks for veterinarians, medical doctors, clinical laboratories, health authorities, and legislators who deal with brucellosis, a disease that is particularly relevant in low- and middle-income countries. Based on all this information, we urge microbiologists, bacterial collections, genomic databases, journals, and public health boards to keep the Brucella and genera separate to avoid further bewilderment and harm.
Topics: Ochrobactrum; Brucella; Terminology as Topic; Phylogeny; Brucellosis; Humans; Opportunistic Infections
PubMed: 37395662
DOI: 10.1128/jcm.00438-23 -
International Journal of Molecular... Dec 2021Brucellosis is a highly prevalent zoonotic disease caused by . spp. are gram-negative facultative intracellular parasitic bacteria. Its intracellular survival and... (Review)
Review
Brucellosis is a highly prevalent zoonotic disease caused by . spp. are gram-negative facultative intracellular parasitic bacteria. Its intracellular survival and replication depend on a functional virB system, an operon encoded by VirB1-VirB12. Type IV secretion system (T4SS) encoded by the virB operon is an important virulence factor of . It can subvert cellular pathway and induce host immune response by secreting effectors, which promotes replication in host cells and induce persistent infection. Therefore, this paper summarizes the function and significance of the VirB system, focusing on the structure of the VirB system where VirB T4SS mediates biogenesis of the endoplasmic reticulum (ER)-derived replicative containing vacuole (rBCV), the effectors of T4SS and the cellular pathways it subverts, which will help better understand the pathogenic mechanism of and provide new ideas for clinical vaccine research and development.
Topics: Animals; Brucella; Brucellosis; Host-Pathogen Interactions; Humans; Operon; Type IV Secretion Systems; Virulence Factors
PubMed: 34948430
DOI: 10.3390/ijms222413637 -
Revista Chilena de Infectologia :... Aug 2018
Topics: Anti-Bacterial Agents; Culture Media; Ochrobactrum anthropi
PubMed: 30534931
DOI: 10.4067/s0716-10182018000400431 -
Emerging Infectious Diseases 1997Brucellosis remains a major zoonosis worldwide. Although many countries have eradicated Brucella abortus from cattle, in some areas Brucella melitensis has emerged as a... (Review)
Review
Brucellosis remains a major zoonosis worldwide. Although many countries have eradicated Brucella abortus from cattle, in some areas Brucella melitensis has emerged as a cause of infection in this species as well as in sheep and goats. Despite vaccination campaigns with the Rev 1 strain, B. melitensis remains the principal cause of human brucellosis. Brucella suis is also emerging as an agent of infection in cattle, thus extending its opportunities to infect humans. The recent isolation of distinctive strains of Brucella from marine mammals has extended its ecologic range. Molecular genetic studies have demonstrated phylogenetic affiliation to Agrobacterium, Phyllobacterium, Ochrobactrum, and Rhizobium. Polymerase chain reaction and gene probe development may provide more effective typing methods. Pathogenicity is related to production of lipopolysaccharides containing a poly N-formyl perosamine O chain, CuZn superoxide dismutase, erythrlose phosphate dehydrogenase, stress-induced proteins related to intracellular survival, and adenine and guanine monophosphate inhibitors of phagocyte functions. Protective immunity is conferred by antibody to lipopolysaccharide and T-cell-mediated macrophage activation triggered by protein antigens. Diagnosis still centers on isolation of the organism and serologic test results, especially enzyme immunoassay, which is replacing other methods. Polymerase chain reaction is also under evaluation. Therapy is based on tetracyclines with or without rifampicin, aminoglycosides, or quinolones. No satisfactory vaccines against human brucellosis are available, although attenuated purE mutants appear promising.
Topics: Animals; Antigens, Bacterial; Brucella; Brucellosis; Cattle; Humans
PubMed: 9204307
DOI: 10.3201/eid0302.970219 -
Journal of Infection in Developing... Nov 2014Brucellosis is a highly contagious zoonosis that affects the public health and economic performance of endemic as well as non-endemic countries. In developing nations,... (Review)
Review
Brucellosis is a highly contagious zoonosis that affects the public health and economic performance of endemic as well as non-endemic countries. In developing nations, brucellosis is often a very common but neglected disease. The purpose of this review is to provide insight about brucellosis in animal populations in Egypt and help to understand the situation from 1986 to 2013. A total of 67 national and international scientific publications on serological investigations, isolation, and biotyping studies from 1986 to 2013 were reviewed to verify the current status of brucellosis in animal populations in Egypt. Serological investigations within the national surveillance program give indirect proof for the presence of brucellosis in cattle, buffaloes, sheep, goats, and camels in Egypt. Serologic testing for brucellosis is a well-established procedure in Egypt, but most of the corresponding studies do not follow the scientific standards. B. melitensis biovar (bv) 3, B. abortus bv 1, and B. suis bv 1 have been isolated from farm animals and Nile catfish. Brucellosis is prevalent nationwide in many farm animal species. There is an obvious discrepancy between official seroprevalence data and data from scientific publications. The need for a nationwide survey to genotype circulating Brucellae is obvious. The epidemiologic situation of brucellosis in Egypt is unresolved and needs clarification.
Topics: Animals; Animals, Domestic; Brucella; Brucellosis; Catfishes; Egypt; Seroepidemiologic Studies
PubMed: 25390047
DOI: 10.3855/jidc.4872 -
Frontiers in Cellular and Infection... 2024consists of gram-negative bacteria that have the ability to invade and replicate in professional and non-professional phagocytes, and its prolonged persistence in the... (Review)
Review
consists of gram-negative bacteria that have the ability to invade and replicate in professional and non-professional phagocytes, and its prolonged persistence in the host leads to brucellosis, a serious zoonosis. Toll-like receptors (TLRs) are the best-known sensors of microorganisms implicated in the regulation of innate and adaptive immunity. In particular, TLRs are transmembrane proteins with a typical structure of an extracellular leucine-rich repeat (LRR) region and an intracellular Toll/interleukin-1 receptor (TIR) domain. In this review, we discuss infection and the aspects of host immune responses induced by pathogens. Furthermore, we summarize the roles of TLRs in infection, with substantial emphasis on the molecular insights into its mechanisms of action.
Topics: Humans; Toll-Like Receptors; Brucellosis; Brucella; Immunity, Innate
PubMed: 38533384
DOI: 10.3389/fcimb.2024.1342684 -
Future Microbiology Jun 2010Taxonomy and nomenclature represent man-made systems designed to enhance understanding of the relationship between organisms by comparison of discrete sets of... (Review)
Review
Taxonomy and nomenclature represent man-made systems designed to enhance understanding of the relationship between organisms by comparison of discrete sets of properties. Initial efforts at bacterial taxonomy were flawed as a result of the previous use of nonsystematic approaches including common names resulting in confusing and inaccurate nomenclature. A decision was made to start afresh with bacterial nomenclature and to avoid the hazards experienced in the taxonomic classification of higher organisms. This was achieved by developing new rules designed to simplify classification and avoid unnecessary and confusing changes. This article reviews the work of a number of scientists attempting to reconcile new molecular data describing the phylogenetic relationship between Brucella organisms and a broader family of organisms with widely variant phenotypes that include human virulence and host range against a backdrop of strict regulatory requirements that fail to recognize significant differences between organisms with similar nomenclature.
Topics: Animals; Brucella; DNA, Bacterial; Evolution, Molecular; Genome, Bacterial; Humans; Phylogeny; Terminology as Topic
PubMed: 20521932
DOI: 10.2217/fmb.10.52 -
PloS One 2020Brucellosis is a zoonotic disease known to be endemic to parts of western and sub-Saharan Africa. However, the epidemiology for humans and animals remains largely... (Review)
Review
Brucellosis is a zoonotic disease known to be endemic to parts of western and sub-Saharan Africa. However, the epidemiology for humans and animals remains largely unknown in many of these countries with Cameroon being a typical example. Despite common knowledge that brucellosis affects livestock, the actual number of infected animals remains unknown. Through a scoping review, the current known status of the disease is described. The aim is to ascertain relevant and publicly accessible research and knowledge of human and animal brucellosis in the country, and to provide an overview of the factors associated with its known persistence. Seroprevalence has been estimated and published in 12 separate instances (1 human; 9 cattle; 1 human and cattle; and 1 that includes cattle, pigs, and small ruminants), between 1982 and 2020, in 9 of the country's 10 geopolitical regions. In 1983, Brucella abortus and B. melitensis were isolated in cattle, but no further bacterial isolation has been published since. The seroprevalence from 196 total humans has ranged between 5.6% and 28.1%, and between 3.0% and 30.8% for 14,044 total cattle. As there is no ongoing surveillance program, it is not currently possible to identify the specific Brucella spp. that are endemic to the country and its regions. There are sufficient agricultural systems of cattle, pigs, goats, and sheep to sustain the presence of multiple Brucella spp. Surveillance information is the cornerstone of epidemiologic decision making, and is needed to direct policy makers, public health authorities, and veterinary services to appropriate actions. A combination of serological and molecular based diagnostics for surveillance is necessary to identify, quantify, and direct the appropriate public health interventions. Cameroon has an opportunity to build public and animal health infrastructure, leading the way for central Africa in the management and future eradication of brucellosis.
Topics: Animals; Brucella abortus; Brucella melitensis; Brucellosis; Cameroon; Endemic Diseases; Epidemiological Monitoring; Humans; Livestock; Seroepidemiologic Studies; Zoonoses
PubMed: 32986759
DOI: 10.1371/journal.pone.0239854