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BMC Veterinary Research Feb 2022Azerbaijan currently ranks thirteenth in global incidence of human brucellosis, with an estimated annual incidence through 2000 at over 50 cases per million. Brucella...
BACKGROUND
Azerbaijan currently ranks thirteenth in global incidence of human brucellosis, with an estimated annual incidence through 2000 at over 50 cases per million. Brucella melitensis has been isolated from patients and is thought to have been acquired through contact with small ruminants or as a foodborne infection. To reduce the burden of human brucellosis, the Azerbaijani government began in 2002, a nationwide vaccination control campaign in small ruminants. There is serological evidence of bovine brucellosis (presumably due to Brucella abortus) in Azerbaijan, but no prevalence estimates were available when this study started in March 2017. The aim of this study was to isolate and identify Brucella spp. from cow milk in the Ganja region, where brucellosis takes a heavy toll on humans and livestock.
RESULTS
Blood and milk samples were collected from cows (n = 1075) in early lactation (up to 90-days) in farms that had a history of previous positive serological results and abortions. Twenty-two out of 57 milk samples collected from seropositive cows, showed growth on Farrell's media, when incubated with 5% CO. Eight additional milk samples showed growth in the absence of CO. The classical biotyping classified them as Brucella abortus (22) and Brucella melitensis (8). RT-PCR confirmed that strains belonged to the genus Brucella. MLVA profiles were obtained for DNA extracted from two B. abortus and six B. melitensis strains. While the B. abortus genetic profile was described in the MLVA database, matching the profile of B. abortus strains isolated in East Europe, Central Asia and China, we found a new genotype for the B. melitensis strains isolated in Azerbaijan, clustering with strains belonging to the American clade, rarely identified in the region.
CONCLUSION
Despite the implementation of the vaccination program in small ruminants, our results suggest that spill-over events of B. melitensis from small ruminants to cattle have occurred. However, cattle are likely to be primarily infected with B. abortus, which warranted the implementation of a bovine brucellosis program. Such a program started in fall 2017. In the Ganja region, cattle should be considered as a potential source of B. abortus and B. melitensis for humans.
Topics: Animals; Azerbaijan; Brucella abortus; Brucella melitensis; Brucellosis; Cattle; Female; Humans; Milk; Multilocus Sequence Typing; Pregnancy
PubMed: 35168621
DOI: 10.1186/s12917-022-03155-1 -
Veterinary Medicine and Science Jul 2022Abortions cause tremendous economic losses in food-producing animals and may lead to food insecurity.
BACKGROUND
Abortions cause tremendous economic losses in food-producing animals and may lead to food insecurity.
OBJECTIVES
This study aimed to characterize Brucella spp. and other abortigenic pathogens from aborted tissues of cattle.
METHODS
For cattle, aborted tissues (n = 19) were cultured, and Brucella spp. were detected using the genus-specific 16S-23S ribosomal DNA interspacer region (ITS) assay and speciated using Brucella abortus, Brucella melitensis, Brucella ovis, and Brucella suis (AMOS) and Bruce-ladder PCR assays. Brucella negative samples were screened using the eight abortigenic pathogens PCR panel. Samples from an abortion outbreak that occurred within a goat tribe were included in this investigation. Sera of females (n = 8) and males (n = 2) were analyzed using the Rose Bengal Test (RBT) and indirect enzyme-linked immunosorbent assay (i-ELISA), while vaginal swabs (n = 3) and aborted tissues (n = 1) were cultured and characterized.
RESULTS
The ITS-PCR detected Brucella DNA in cultures from two aborted tissues of cattle (10.5%, [2/19]), which were identified as B. melitensis (n = 1), and B. abortus (n = 1) using AMOS and Bruce-ladder PCR assays. Campylobacter fetus (n = 7) and Leptospira spp. (n = 4) including co-infections (n = 2) of C. fetus and Leptospira spp. were identified from the Brucella negative samples of cattle. Goats (100.0%, 10/10) were brucellosis seropositive on RBT and i-ELISA. Mixed infections caused by B. melitensis and B. abortus were isolated from the vaginal swabs (n = 3) and aborted tissues (n = 1).
DISCUSSION AND CONCLUSIONS
This is the first identification of abortion-associated pathogens in aborted cattle indicating the enormous financial losses and a threat to public health. It is therefore essential to include these identified pathogens in the surveillance scheme of veterinary and human services.
Topics: Animals; Brucella; Brucella abortus; Brucella melitensis; Brucella ovis; Brucella suis; Brucellosis; Cattle; Cattle Diseases; Female; Goat Diseases; Goats; Leptospira; Male; Pregnancy; Rwanda
PubMed: 35420251
DOI: 10.1002/vms3.805 -
Asian Pacific Journal of Tropical... Dec 2016Brucellosis is a zoonotic disease characterized by reproductive failure in animals and undulent fever in humans. In cattle, it is caused by Brucella abortus while in... (Review)
Review
Brucellosis is a zoonotic disease characterized by reproductive failure in animals and undulent fever in humans. In cattle, it is caused by Brucella abortus while in goats by Brucella melitensis, the main cause of brucellosis in humans. Brucellosis in livestock has been associated with importation of animals from breeder herd of unknown disease status. The prevalence of bovine brucellosis Brucella abortus in 2014 ranged between 1% and 2% in Thailand and Indonesia, and 4%-5% in Malaysia and Myanmar. Prevalence of goat brucellosis Brucella melitensis is approximately 1% in Malaysia and Thailand. 'Test-and-slaughter' is the general policy against brucellosis adopted by most ASEAN countries to eradicate the disease. Under this program, the Rose Bengal Plate Test (RBPT) is used as the screening test to identify infected farm/herd while the complement fixation test (CFT) is the confirmatory test. The test-and-slaughter eradication strategy that was implemented since 1979 had managed to keep the prevalence rate to less than 5%, from 3.3% in 1979, 0.23% in 1988, 1% in 1998 and 5% in 2016. The test-and-slaughter program seemed effective in reducing the prevalence of brucellosis but was unable to eradicate the disease due to several factors, which include failure to locate and identify the remaining affected animals and to control their movement, importation of breeder animals from non-brucellosis free countries and lack of participation by the farmers following unreliable test results. To support the eradication policy, research activities since 1980s have suggested combinations of serological tests to improve diagnosis while surveillance should be focused on hotspots areas. The prevalence can be further reduced by strictly sourcing breeder animals from brucella-free areas or countries.
PubMed: 27955740
DOI: 10.1016/j.apjtm.2016.11.007 -
Infection and Drug Resistance 2023Brucellosis is a serious public health issue in Qinghai (QH), China. Surveying the seroprevalence and isolation of strains from marmots is key to understanding the role...
OBJECTIVE
Brucellosis is a serious public health issue in Qinghai (QH), China. Surveying the seroprevalence and isolation of strains from marmots is key to understanding the role of wildlife in the maintenance and spread of brucellosis.
METHODS
In this study, a set of methods, including a serology survey, bacteriology, antibiotic susceptibility, molecular genotyping (MLST and MLVA), and genome sequencing, were employed to characterize the two strains.
RESULTS
The seroprevalence of brucellosis in marmots was 7.0% (80/1146) by serum tube agglutination test (SAT); one strain was recovered from these positive samples, and another strain from a human. Two strains were identified as bv. 1 and were susceptible to all eight drugs examined. The distribution patterns of the accessory genes, virulence associated genes, and resistance genes of the two strains were consistent, and there was excellent collinearity between the two strains on chromosome I, but they had significant SVs in chromosome II, including inversions and translocations. MLST genotyping identified two strains as ST2, and MLVA-16 analysis showed that the two strains clustered with strains from northern China. WGS-SNP phylogenetic analysis showed that the strains were genetically homogeneous with strains from the northern region, implying that strains from a common lineage were spread continuously in different regions and hosts.
CONCLUSION
Seroprevalence and molecular clues demonstrated frequent direct or indirect contact between sheep/goats, cattle, and marmots, implying that wildlife plays a vital role in the maintenance and spread of in the Qinghai-Tibet Plateau.
PubMed: 38144222
DOI: 10.2147/IDR.S436950 -
Veterinary Research Aug 2023The process of intracellular proteolysis through ATP-dependent proteases is a biologically conserved phenomenon. The stress responses and bacterial virulence of various...
The process of intracellular proteolysis through ATP-dependent proteases is a biologically conserved phenomenon. The stress responses and bacterial virulence of various pathogenic bacteria are associated with the ATP-dependent Clp protease. In this study, a Brucella abortus 2308 strain, ΔclpP, was constructed to characterize the function of ClpP peptidase. The growth of the ΔclpP mutant strain was significantly impaired in the TSB medium. The results showed that the ΔclpP mutant was sensitive to acidic pH stress, oxidative stress, high temperature, detergents, high osmotic environment, and iron deficient environment. Additionally, the deletion of clpP significantly affected Brucella virulence in macrophage and mouse infection models. Integrated transcriptomic and proteomic analyses of the ΔclpP strain showed that 1965 genes were significantly affected at the mRNA and/or protein levels. The RNA-seq analysis indicated that the ΔclpP strain exhibited distinct gene expression patterns related to energy production and conversion, cell wall/membrane/envelope biogenesis, carbohydrate transport, and metabolism. The iTRAQ analysis revealed that the differentially expressed proteins primarily participated in amino acid transport and metabolism, energy production and conversion, and secondary metabolites biosynthesis, transport and catabolism. This study provided insights into the preliminary molecular mechanism between Clp protease to bacterial growth, stress response, and bacterial virulence in Brucella strains.
Topics: Animals; Mice; Peptide Hydrolases; Brucella abortus; Endopeptidase Clp; Proteomics; Virulence; Disease Models, Animal
PubMed: 37612737
DOI: 10.1186/s13567-023-01200-x -
Seminars in Immunopathology Feb 2017The innate immune system is essential for the detection and elimination of bacterial pathogens. Upon inflammasome activation, caspase-1 cleaves pro-IL-1β and pro-IL-18... (Review)
Review
The innate immune system is essential for the detection and elimination of bacterial pathogens. Upon inflammasome activation, caspase-1 cleaves pro-IL-1β and pro-IL-18 to their mature forms IL-1β and IL-18, respectively, and the cell undergoes inflammatory death termed pyroptosis. Here, we reviewed recent findings demonstrating that Brucella abortus ligands activate NLRP3 and AIM2 inflammasomes which lead to control of infection. This protective effect is due to the inflammatory response caused by IL-1β and IL-18 rather than cell death. Brucella DNA is sensed by AIM2 and bacteria-induced mitochondrial reactive oxygen species is detected by NLRP3. However, deregulation of pro-inflammatory cytokine production can lead to immunopathology. Nervous system invasion by bacteria of the genus Brucella results in an inflammatory disorder termed neurobrucellosis. Herein, we discuss the mechanism of caspase-1 activation and IL-1β secretion in glial cells infected with B. abortus. Our results demonstrate that the ASC inflammasome is indispensable for inducing the activation of caspase-1 and secretion of IL-1β upon infection of astrocytes and microglia with Brucella. Moreover, our results demonstrate that secretion of IL-1β by Brucella-infected glial cells depends on NLRP3 and AIM2 and leads to neurobrucellosis. Further, the inhibition of the host cell inflammasome as an immune evasion strategy has been described for bacterial pathogens. We discuss here that the bacterial type IV secretion system VirB is required for inflammasome activation in host cells during infection. Taken together, our results indicate that Brucella is sensed by ASC inflammasomes mainly NLRP3 and AIM2 that collectively orchestrate a robust caspase-1 activation and pro-inflammatory response.
Topics: Animals; Brucella abortus; Brucellosis; Central Nervous System; DNA, Bacterial; DNA-Binding Proteins; Dendritic Cells; Humans; Immunity, Innate; Inflammasomes; NLR Family, Pyrin Domain-Containing 3 Protein
PubMed: 27405866
DOI: 10.1007/s00281-016-0581-1 -
BMC Microbiology Feb 2017Brucellosis is a common and chronic disease of cattle and other bovids that often causes reproductive disorders. Natural infection in cattle is caused by Brucella...
BACKGROUND
Brucellosis is a common and chronic disease of cattle and other bovids that often causes reproductive disorders. Natural infection in cattle is caused by Brucella abortus and transmission typically occurs during abortions, calving, or nursing. Brucellosis is also a major zoonotic disease due to contamination of dairy products or contact with the tissues of infected animals. Brucellosis has been eradicated from most of the developed world in the last 40 years but persists in many regions-the disease remains prevalent in portions of Africa, the Middle East, Asia, and Central and South America, as well as in the Mediterranean basin. In Italy, B. abortus has persisted in southern regions in both cattle and water buffalo. Previous attempts at analyzing the phylogenetics of B. abortus in Italy have been challenging due to limited genetic variability and unresolved global population genetic structure of this pathogen.
RESULTS
We conducted genome-wide phylogenetic analyses on 11 representative strains of B. abortus from Italy, and compared these sequences to a worldwide collection of publically available genomes. Italian isolates belong to three clades that are basal to the main and global B. abortus lineage. Using six SNP-based assays designed to identify substructure within the Italian clades, we surveyed a collection of 261 isolates and found that one clade predominates throughout endemic districts in the country, while the other two clades are more geographically restricted to portions of southern Italy.
CONCLUSIONS
Although related strains exist worldwide, B. abortus isolates from Italy are substantially different than those found in much of the rest of Europe and North America, and are more closely related to strains from the Middle East and Asia. Our assays targeting genetic substructure within Italy allowed us to identify the major lineages quickly and inexpensively, without having to generate whole genome sequences for a large isolate collection. These findings highlight the importance of genetic studies to assess the status and the history of pathogens.
Topics: Africa; Animals; Asia; Brucella abortus; Brucellosis; Buffaloes; Cattle; Cattle Diseases; Cluster Analysis; DNA, Bacterial; Europe; Genetic Variation; Genotype; Geographic Mapping; Italy; Molecular Typing; North America; Phylogeny; Zoonoses
PubMed: 28152976
DOI: 10.1186/s12866-017-0939-0 -
Nature Communications Jan 2023The cell nucleus is a primary target for intracellular bacterial pathogens to counteract immune responses and hijack host signalling pathways to cause disease. Here we...
The cell nucleus is a primary target for intracellular bacterial pathogens to counteract immune responses and hijack host signalling pathways to cause disease. Here we identify two Brucella abortus effectors, NyxA and NyxB, that interfere with host protease SENP3, and this facilitates intracellular replication of the pathogen. The translocated Nyx effectors directly interact with SENP3 via a defined acidic patch (identified from the crystal structure of NyxB), preventing nucleolar localisation of SENP3 at late stages of infection. By sequestering SENP3, the effectors promote cytoplasmic accumulation of nucleolar AAA-ATPase NVL and ribosomal protein L5 (RPL5) in effector-enriched structures in the vicinity of replicating bacteria. The shuttling of ribosomal biogenesis-associated nucleolar proteins is inhibited by SENP3 and requires the autophagy-initiation protein Beclin1 and the SUMO-E3 ligase PIAS3. Our results highlight a nucleomodulatory function of two Brucella effectors and reveal that SENP3 is a crucial regulator of the subcellular localisation of nucleolar proteins during Brucella infection, promoting intracellular replication of the pathogen.
Topics: Humans; Nuclear Proteins; Cell Nucleus; Brucella abortus; Cell Nucleolus; Brucellosis; Molecular Chaperones; Protein Inhibitors of Activated STAT; Cysteine Endopeptidases
PubMed: 36609656
DOI: 10.1038/s41467-022-35763-8 -
Iranian Journal of Biotechnology Sep 2019Using Strain 19 (S19) to control bovine brucellosis is restricted due to induce antibodies to the O-side chain of the smooth lipopolysaccharide (LPS) which may be...
BACKGROUND
Using Strain 19 (S19) to control bovine brucellosis is restricted due to induce antibodies to the O-side chain of the smooth lipopolysaccharide (LPS) which may be difficult to differentiate vaccinated and infected animals. Furthermore, it is virulent for humans and can induce abortion to cattle.
OBJECTIVES
The aim of this study was to employ gene knockout S19 for the first time to eliminate diagnostic defects and obtain the attenuated mutant strain.
MATERIAL AND METHODS
The gene, which is one of the LPS O-chain coding genes, was knocked out in vaccinal S19. The proliferative response and immunoglobulin M production were analyzed in deletion strain-infected BALB/c mice.
RESULTS
The loss of gene function resulted in induction of the splenocyte proliferative response in mice infected by the mutant S19 strain compare to those induced by parental S19 and RB51 strains. Moreover, mutant did not induce any IgM antibody response using the enzyme-linked immunosorbent assay.
CONCLUSIONS
As a result, the new mutant S19 strain had deficiency in its LPS O-chain structure, besides cannot induce IgM response then, reduce mistakes to discriminate between vaccinated and infected animal, and also can be considered as a new vaccine candidate.
PubMed: 32195284
DOI: 10.29252/ijb.2159 -
PloS One 2022Brucellosis is an endemic zoonotic disease caused by Brucella species, which are intramacrophage pathogens that make treating this disease challenging. The negative...
Brucellosis is an endemic zoonotic disease caused by Brucella species, which are intramacrophage pathogens that make treating this disease challenging. The negative effects of the treatment regime have prompted the development of new antimicrobials against brucellosis. A new treatment modality for antibiotic-resistant microorganisms is the use of nanoparticles (NPs). In this study, we examined the antibacterial activities of silver and gold NPs (SNPs and GNPs, respectively), the resistance developed by Brucella melitensis (B. melitensis) and Brucella abortus (B. abortus) strains and the toxicity of both of these NPs in experimental rats. To test the bactericidal effects of the SNPs and GNPs, we used 22 multidrug-resistant Brucella isolates (10 B. melitensis and 12 B. abortus). The minimal inhibitory concentrations (MICs) of both types of NPs were determined utilizing the microdilution technique. To test the stability of resistance, 7 B. melitensis and 6 B. abortus isolates were passaged ten times in culture with subinhibitory concentrations of NPs and another ten times without NPs. Histopathological analysis was completed after rats were given 0.25, 0.5, 1, and 2 mg/kg NPs orally for 28 consecutive days. The MIC values (μg/ml) of the 10-nm SNPs and 20-nm GNPs against B. melitensis were 22.43 ± 2.32 and 13.56 ± 1.22, while these values were 18.77 ± 1.33 and 12.45 ± 1.59 for B. abortus, respectively. After extensive in vitro exposure, most strains showed no resistance to the 10-nm SNPs or 20-nm GNPs. The NPs and antibiotics did not cross-react in any of the evolved Brucella strains. SNPs and GNPs at doses below 2 mg/kg were not harmful to rat tissue according to organ histopathological examinations. However, a greater dose of NPs (2 mg/kg) harmed all of the tissues studied. The bactericidal properties of NPs are demonstrated in this work. Brucella strains develop similar resistance to SNPs and GNPs, and at low dosages, neither SNPs nor GNPs were hazardous to rats.
Topics: Animals; Anti-Bacterial Agents; Brucella; Brucella abortus; Brucella melitensis; Brucellosis; Gold; Gold Compounds; Metal Nanoparticles; Rats; Silver; Silver Compounds
PubMed: 35834538
DOI: 10.1371/journal.pone.0269963