National epidemiology of culture-confirmed brucellosis in Israel, 2004-2022.

Brucellosis, a global zoonosis, is endemic in Israel. We used a national database of culture-confirmed cases (2004-2022) to analyse the trends of brucellosis. Of 2,489 unique cases, 99.8% were bacteraemic, 64% involved males, and the mean age was 30.5 years. Brucella melitensis was the dominant species (99.6%). Most cases occurred among the Arab sector (84.9%) followed by the Jewish (8.5%) and Druze (5.5%) sectors. The average annual incidence rates overall and for the Arab, Druze, and Jewish sectors were 1.6/100,000, 6.6/100,000, 5.5/100,000, and 0.18/100,000, respectively. The annual incidence rates among the Arab (incidence rate ratio (IRR) = 36.4) and the Druze (IRR = 29.6) sectors were significantly higher than among the Jewish sector (p < 0.001). The highest incidence rates among the Arab sector occurred in the South District, peaking at 41.0/100,000 in 2012. The frequencies of B. melitensis isolated biotypes (biotype 1 - 69.1%, biotype 2 - 26.0%, and biotype 3 - 4.3%) differed from most Middle Eastern and European countries. A significant switch between the dominant biotypes was noted in the second half of the study period. Efforts for control and prevention should be sustained and guided by a One Health approach mindful of the differential trends and changing epidemiology.

Investigating the mechanism of rough phenotype in a naturally attenuated Brucella strain: insights from whole genome sequencing.

Objective: Brucellosis, a significant zoonotic disease, not only impacts animal health but also profoundly influences the host immune responses through gut microbiome. Our research focuses on whole genome sequencing and comparative genomic analysis of these Brucella strains to understand the mechanisms of their virulence changes that may deepen our comprehension of the host immune dysregulation. Methods: The Brucella melitensis strain CMCC55210 and its naturally attenuated variant CMCC55210a were used as models. Biochemical identification tests and in vivo experiments in mice verified the characteristics of the strain. To understand the mechanism of attenuation, we then performed de novo sequencing of these two strains. Results: We discovered notable genomic differences between the two strains, with a key single nucleotide polymorphism (SNP) mutation in the manB gene potentially altering lipopolysaccharide (LPS) structure and influencing host immunity to the pathogen. This mutation might contribute to the attenuated strain's altered impact on the host's macrophage immune response, overing insights into the mechanisms of immune dysregulation linked to intracellular survival. Furthermore, we explore that manipulating the Type I restriction-modification system in Brucella can significantly impact its genome stability with the DNA damage response, consequently affecting the host's immune system. Conclusion: This study not only contributes to understanding the complex relationship between pathogens, and the immune system but also opens avenues for innovative therapeutic interventions in inflammatory diseases driven by microbial and immune dysregulation.

Rev1Δwzm vaccine candidate is safe in young and adult sheep and protects against Brucella ovis infection in rams.

Small ruminants affected by brucellosis, caused mainly by Brucella melitensis and B. ovis, suffer reproductive disorders, leading to significant economic losses worldwide. Vaccination is an essential tool to prevent the disease in ovine and caprine livestock, but the only vaccine recommended to date is B. melitensis Rev1, which in sheep is only safe for use in lambs aged 3-4 months. This restriction poses considerable practical challenges for the implementation of Rev1 in countries with endemic brucellosis and/or limited resources, where there is a need for mass vaccination with a safe vaccine to control the disease in both animals and humans. We recently developed a B. melitensis strain Rev1Δwzm showing superior vaccine properties in mice and safety in pregnant ewes. Here, we report that Rev1Δwzm (i) is safe in young and adult sheep, both male and female; (ii) induces a transient serological response in the Rose Bengal test in ≤50 % of sheep, confirmed to some extent by the complement fixation test, and a stronger, more persistent anti- rough-LPS response; and (iii) protects rams against a B. ovis challenge 25 weeks after vaccination. To resolve the problem of serological interference, the use of green fluorescent protein tagging strategy allowed us to identify vaccinated sheep with only a single inoculation. These results, together with the previously reported safety in pregnant ewes, position Rev1Δwzm as a firm vaccine candidate and a promising alternative to Rev1. Further experiments are warranted to assess its efficacy against B. melitensis in pregnant ewes.

Co-delivery of doxycycline and rifampicin using CdTe-labeled poly (lactic-co-glycolic) acid for treatment of Brucella melitensis infection.

Brucellosis poses a significant challenge in the medical field as a systemic infection with a propensity for relapse. This study presented a novel approach to brucellosis treatment, enhancing the efficacy of doxycycline and rifampicin through the use of poly (lactic-co-glycolic) acid coupled with cadmium-telluride quantum dots (Dox-Rif-PLGA@CdTe). The double emulsion solvent evaporation method was employed to prepare Dox-Rif-PLGA@CdTe. The study scrutinized the physicochemical attributes of these nanoparticles. The impact of antibiotic-loaded nanoparticles on Brucella melitensis was evaluated through well diffusion, minimum inhibitory concentration (MIC), and cell culture. The chemical analysis results demonstrated a possibility of chemical reactions occurring among the constituents of nanoparticles. Assessments using the well diffusion and MIC methods indicated that the impact of free drugs and nanoparticles on bacteria was equivalent. However, the drug-loaded nanoparticles significantly decreased the colony-forming units (CFUs) within the cell lines compared to free drugs. In conclusion, the synthesis of nanoparticles adhered to environmentally friendly practices and demonstrated safety. The sustained drug release over 100 h facilitated drug accumulation at the bacterial site, resulting in a heightened therapeutic effect on B. melitensis and improved outcomes in brucellosis treatment. The application of these synthesized nanodrugs exhibited promising therapeutic potential.

Brucella melitensis Rev1Δwzm: Placental pathogenesis studies and safety in pregnant ewes.

One of the main causes of human brucellosis is Brucella melitensis infecting small ruminants. To date, Rev1 is the only vaccine successfully used to control ovine and caprine brucellosis. However, it is pathogenic for pregnant animals, resulting in abortions and vaginal and milk shedding, as well as being infectious for humans. Therefore, there is an urgent need to develop an effective vaccine that is safer than Rev1. In efforts to further attenuate Rev1, we recently used wzm inactivation to generate a rough mutant (Rev1Δwzm) that retains a complete antigenic O-polysaccharide in the bacterial cytoplasm. The aim of the present study was to evaluate the placental pathogenicity of Rev1Δwzm in trophoblastic cells, throughout pregnancy in mice, and in ewes inoculated in different trimesters of pregnancy. This mutant was evaluated in comparison with the homologous 16MΔwzm derived from a virulent strain of B. melitensis and the naturally rough sheep pathogen B. ovis. Our results show that both wzm mutants triggered reduced cytotoxic, pro-apoptotic, and pro-inflammatory signaling in Bewo trophoblasts, as well as reduced relative expression of apoptosis genes. In mice, both wzm mutants produced infection but were rapidly cleared from the placenta, in which only Rev1Δwzm induced a low relative expression of pro-apoptotic and pro-inflammatory genes. In the 66 inoculated ewes, Rev1Δwzm was safe and immunogenic, displaying a transient serological interference in standard RBT but not CFT S-LPS tests; this serological response was minimized by conjunctival administration. In conclusion, these results support that B. melitensis Rev1Δwzm is a promising vaccine candidate for use in pregnant ewes and its efficacy against B. melitensis and B. ovis infections in sheep warrants further study.

The first human case report of molecularly confirmed co-infection of Brucella melitensis and Coxiella burnetii: A case report.

Co-infection with Brucella melitensis and Coxiella burnetii has been rarely reported. To date, there are only two co-infection case reports from Croatia and China which diagnosed the infections mainly through the use of serological tests. In this report, we present the first case of molecularly confirmed B. melitensis bacteremia and C. burnetii spondylodiscitis co-infection in a goat dairy farmer who presented with lumbosacral spondylodiscitis and bilateral psoas abscesses. From the blood culture, B. melitensis was identified by using 16S rRNA gene sequencing and specific PCR. Lumbar bone tissue was found to be positive for C. burnetii using multiplex real-time PCR and was confirmed with a positive result from conventional PCR which detected the infection through the identification of the IS1111 gene. The patient's condition improved after decompressive laminectomy was performed and administration of antibiotics regimen: intravenous gentamicin, oral rifampicin, and oral doxycycline. From our case, it is important to raise awareness of this underreported co-infection with multiple zoonotic diseases, especially Q fever and brucellosis, which share the same exposure risk. Moreover, we also emphasize the use of advanced molecular techniques to improve the diagnostic efficiency and reduce the use of time-consuming procedures among patients who are continuously exposed to such risk factors in areas with high seroprevalence of these zoonotic diseases.

Hemophagocytic lymphohistiocytosis associated with brucellosis.

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening immune disorder categorized as familial HLH or secondary HLH. Our case report describes a 63-year-old woman with epilepsy whose clinical signs were unremitting fever and altered consciousness. Primary abnormalities consisted of fever, splenomegaly, cytopenia, hypertriglyceridemia, hyperferritinemia and hemophagocytosis in the bone marrow. Results of blood next generation sequencing and blood culture confirmed Brucella infection. This report illustrates a sHLH case caused by Brucella melitensis infection. Here, we review the classification, clinical features, diagnostic methods, treatment regimens, differential diagnosis, and prognosis of HLH and brucellosis.

An unusual case of Brucella melitensis-related wound infection.

Background: Brucellosis is an anthropo-zoonotic infectious disease caused by various Brucella species. It is usually transmitted through contact with infected animals or consumption of contaminated animal products. Brucellosis most commonly affects the musculoskeletal and reticuloendothelial system with additional involvement observed in gastrointestinal system, urinary tract, reproductive system, central nervous system, and cardiovascular system. Skin involvement is extremely rare in brucellosis. Here, we report a rare case of Brucella melitensis infection developing in a back wound following a lumbar disc herniation surgery over 14 years ago. Case: A 34-year-old male patient, who had a herniated disc surgery 14 years ago, was admitted to the hospital with complaints of joint pain, sweating and discharge at the surgery site. Wound culture revealed the presence of Gram negative cocobacilli which was identified as Brucella melitensis. The subsequent diagnostic tests, including the Rose-Bengal and Brucella Capture test positivity at a titer of 1/320 confirmed the diagnosis. The patient received six weeks of doxycycline (200 mg/day, orally) and rifampin (600 mg/day orally) treatment, accompanied by wound care procedures. Daily cleaning, sterile dressing, and wound debridement were employed. Following treatment, the patient's condition improved, and wound discharge ceased. Continuous monitoring showed no signs of relapse, achieving complete remission. Conclusion: Brucella spp. should be considered as a potential cause of wound infections developing after surgery or trauma in brucellosis-endemic areas. This report also emphasizes the importance of promptly determining the cause of infection before initiating antibiotic treatment.

Unveiling Neurobrucellosis: A Case Report Emphasizing Early Diagnosis for Better Outcomes.

Introduction: Brucellosis is a pervasive zoonotic disease causing considerable human morbidity worldwide. This report focuses on a case of neurobrucellosis in a rural Indian patient, emphasizing the need for timely microbiological confirmation given its nonspecific clinical presentation. Case Presentation: A 55-year-old rural Indian farmer presented with a 3 week history of insidious, low-grade fever, myalgia, and arthralgia. He developed acute right-sided weakness and neurological symptoms, including disorientation and neck rigidity. Laboratory tests indicated abnormal blood counts, elevated inflammatory markers, and liver dysfunction. Cerebrospinal fluid analysis showed pleocytosis with lymphomononuclear cells and elevated protein levels. Blood cultures eventually grew Gram-negative coccobacilli. Serological tests confirmed neurobrucellosis. Prompt antibiotic therapy led to clinical and laboratory improvement. Conclusion: This case underscores the importance of recognizing neurobrucellosis, particularly in endemic areas, given its nonspecific clinical presentation. Early microbiological diagnosis, supported by positive blood cultures and serological tests, was crucial. The patient's rapid response to appropriate antibiotics emphasizes the significance of timely recognition and management.

Draft genome sequencing of Brucella melitensis isolated from aborted Iraqi sheep.

Brucellosis remains a significant zoonotic disease, with Brucella melitensis maintaining endemicity in Middle Eastern nations. This study presents the draft genome sequencing of an Iraqi B. melitensis strain, representing a crucial step in monitoring virulence, antimicrobial resistance, and exploring the diversity and evolution of the Brucella genus.

Brucella-driven host N-glycome remodeling controls infection.

Many powerful methods have been employed to elucidate the global transcriptomic, proteomic, or metabolic responses to pathogen-infected host cells. However, the host glycome responses to bacterial infection remain largely unexplored, and hence, our understanding of the molecular mechanisms by which bacterial pathogens manipulate the host glycome to favor infection remains incomplete. Here, we address this gap by performing a systematic analysis of the host glycome during infection by the bacterial pathogen Brucella spp. that cause brucellosis. We discover, surprisingly, that a Brucella effector protein (EP) Rhg1 induces global reprogramming of the host cell N-glycome by interacting with components of the oligosaccharide transferase complex that controls N-linked protein glycosylation, and Rhg1 regulates Brucella replication and tissue colonization in a mouse model of brucellosis, demonstrating that Brucella exploits the EP Rhg1 to reprogram the host N-glycome and promote bacterial intracellular parasitism, thereby providing a paradigm for bacterial control of host cell infection.

Genetic Diversity of Brucella melitensis Isolated from Domestic Ruminants in Iraq.

The control and eradication of brucellosis represents a critical objective for Veterinary and Health Authorities across several countries globally. Efficient surveillance programs play a pivotal role in detecting and managing outbreaks. Epidemiological investigations significantly benefit from standardized and efficient molecular typing techniques and analytical tools, enabling public health laboratories to identify the origin of outbreaks. This study aimed to sequence Brucella spp. strains isolated in Iraq from different ruminant species to verify their molecular epidemiological correlations and, above all, to shed a light on how these Iraqi isolates are positioned in the phylogenetic context of Brucella spp. The 35 isolates under study were from abortion, milk, placenta, and the fetal membranes of sheep, cattle, and buffalo. Genotyping involved various techniques: MLVA-16, Whole Genome Sequencing, MLST, and cgMLST. All the Iraqi isolates from our study clustered in MLVA-16 within the East Mediterranean clade, and all but one grouped together in the same branch of the MST tree. MST analysis showed the minimum distance of one allele between the studied isolates, except for one strain from buffalo, which was positioned farther away from the rest of the isolates. In cgMLST, the majority of strains grouped within a large cluster predominantly comprising genotypes from the Middle East. The application of different control measures in different territories based on molecular epidemiological studies would increase the chances of maximizing public health benefits and minimizing the spread of infection to disease-free or lower prevalence areas.

Molecular epidemiological characteristics of osteoarthritis-associated Brucella melitensis in China: evidence from whole-genome sequencing-based analysis.

BACKGROUND: Brucellosis, developing complications including arthritis, spondylitis, sacroiliitis, and osteomyelitis, is one of the most common zoonotic diseases in the current world which causes economic losses to the livestock industry and is a great public health concern. Brucella melitensis are the main pathogen of brucellosis epidemics in China, most of which are located in northern China. However, there is limited knowledge about the epidemiology of osteoarthritis-associated brucellosis. This study was aimed to reveal the prevalence of osteoarthritis-associated brucellosis in Inner Mongolia and also to investigate the molecular characteristics of B. melitensis isolates. METHODS AND RESULTS: In 2018, the osteoarthritis symptoms of brucellosis in the Brucellosis department of a hospital in Inner Mongolia were investigated. Twenty osteoarthritis-associated B. melitensis strains, isolated from the inpatients in Inner Mongolia during 2013-2017, were subjected to whole genome sequencing. The multilocus sequence type (MLST) and core genome SNP (cgSNP) analysis were conducted to detect molecular epidemiological characteristics. The incidence of brucellosis osteoarthritis symptoms in males (85/120, 70.8%) was significantly higher than that in females (35/120, 29.2%), and the age of patients was concentrated between 41 and 60 years old. In silico analyses indicated ST8 was the prevalent sequence type and the transmission of osteoarthritis-associated B. melitensis among different geographical areas. All strains carry virulence genes, including cgs, lpsA, manCoAg, pgm, pmm, virB4, wbdA and wboA. CONCLUSION: Our study showed the close epidemiologically connection of osteoarthritis-associated B. melitensis strains in northern China. And ST8 was the prevalent sequence type which need our attention.

Brucellosis an Unusual presentation as isolated septic mono-arthritis of the knee joint: A case report.

Brucellosis is a zoonotic infection that is widely spread across the world. It is becoming more common in Middle Eastern countries such as Qatar, Saudi Arabia, and the Mediterranean region. Despite this, we need to remain vigilant as it is still prevalent in many parts of the world. The most common presentation is musculoskeletal, but it can also present as septic arthritis in the sacroiliac, hip, or knee joints. Brucella melitensis was only found in one extended culture of synovial fluid. Treatment involved a combination of antimicrobial therapy using gentamycin, doxycycline, and rifampin. A high level of suspicion for brucellosis is necessary for any patient coming from an endemic region with non-specific and chronic arthritis to ensure early diagnosis and treatment. In this case, we present a 28-year-old male who was diagnosed with Brucellosis after developing acute septic arthritis.

Equine brucellosis in Iran: serological, bacteriological and molecular analysis.

Equine brucellosis significantly impacts the health and functionality of horses, leading to complications such as bursitis infection, septic tenosynovitis, septic arthritis, and non-specific lameness resulting from joint infections. In the present study, we used the Rose Bengal plate agglutination test (RBPT), serum agglutination test (SAT), and the 2-mercaptoethanol (2-ME) assays to find equine brucellosis. From June 2018 to September 2022, 876 blood samples were randomly taken from apparently healthy racing horses in certain parts of Iran, such as Kerman, Isfahan, Tehran, Qom, and Kurdistan. DNA extraction was carried out directly on all 63 serum samples identified as seropositive through RBPT. An additional 30 seronegative serum samples were also randomly chosen for study. Bacterial culture was also done on milk, blood, and vaginal swabs taken from seropositive horses.The bacteria that were found in the samples were then put through Bruce-ladder PCR. Our results indicated that 63 (7.1%), 21 (2.3%), and 2 (0.2%) of horses were seropositive using RBPT, SAT, and 2-ME, respectively. Also, none of the 30 DNA-extracted serum samples from seronegative horses tested positive for Brucella DNA, while 44.5% (28/63) of the DNA samples from seropositive horses yielded positive results for Brucella DNA. Out of the seropositive samples, 26 had DNA from Brucella abortus and 2 had DNA from Brucella melitensis. Also, B. melitensis biovar 1 was found in two milk samples from mares in the provinces of Kerman and Isfahan. It was identified using classical biotyping, and molecular assays. It was seen that some of healthy racing horses in some parts of Iran had antibodies against Brucella. The bacteriology and PCR methodologies provide a more comprehensive and reliable means of identifying Brucella spp. infections in horse, especially when the RBPT test came back positive. This underscores the imperative for employing molecular, bacterial, and serological methods in the diagnosis and monitoring of this zoonotic infection. Additionally, this finding suggests that Brucella is being transmitted to equine hosts as a result of its presence in ruminants. The mechanism of transmission may involve interactions between infected ruminants and susceptible equines. This discovery is significant as it underscores the potential cross-species transmission of Brucella and highlights the importance of understanding and managing the spread of the pathogen in both ruminant and equine populations.

Prevalence of Brucella melitensis and Brucella abortus aminoglycoside-resistant isolates: a systematic review and meta-analysis.

INTRODUCTION: Aminoglycosides are vital antibiotics for treating Brucella infections, because they interfere with bacterial protein production and are often combined with other antibiotics. They are cost-effective, have fewer side effects, and can penetrate biofilms. The prevalence of brucellosis has increased in recent years, increasing the need for effective treatments. In addition, the emergence of multidrug-resistant Brucella strains has highlighted the need for an updated and comprehensive understanding of aminoglycoside resistance. This systematic review aimed to provide a comprehensive overview of the global prevalence of aminoglycoside resistance in B. melitensis and B. abortus. METHODS: A systematic search of online databases was conducted and eligible studies met certain criteria and were published in English. Quality assessment was performed using the JBI Checklist. A random-effects model was fitted to the data, and meta-regression, subgroup, and outlier/influential analyses were performed. The analysis was performed using R and the metafor package. RESULTS: The results of this systematic review and meta-analysis suggested that the average prevalence rates of streptomycin, gentamicin, and amikacin resistance were 0.027 (95% confidence interval [CI], 0.015-0.049), 0.023 (95% CI, 0.017-0.032), and 0.008 (95% CI, 0.002-0.039), respectively. The prevalence of streptomycin resistance was higher in the unidentified Brucella group than in the B. abortus and B. melitensis groups (0.234, 0.046, and 0.017, respectively; p < 0.02). The prevalence of gentamicin resistance increased over time (r = 0.064; 95% CI, 0.018 to 0.111; p = 0.007). The prevalence of resistance did not correlate with the quality score for any antibiotic. Funnel plots showed a potential asymmetry for streptomycin and gentamicin. These results suggest a low prevalence of antibiotic resistance in the studied populations. CONCLUSION: The prevalence of aminoglycoside resistance in B. melitensis and B. abortus was low. However, gentamicin resistance has increased in recent years. This review provides a comprehensive and updated understanding of aminoglycoside resistance in B. melitensis and B. abortus.

Prevalence of Brucella melitensis and Brucella abortus Fluoroquinolones Resistant Isolates: A Systematic Review and Meta-Analysis.

Background: Brucellosis impact both animals and humans worldwide. However, using antibiotics for brucellosis remains controversial despite decades of research. Relapse can complicate treatment in this area. Since the mid-1980s, microbiologists, and physicians have studied fluoroquinolones' use for treating human brucellosis. The principal advantages of fluoroquinolones are their intracellular antimicrobial activity, low nephrotoxicity, good pharmacokinetics, and the lack of drug-level monitoring. Fluoroquinolones inhibit disease recurrence. In vitro and clinical data were used to study the prevalence of Brucella melitensis and Brucella abortus fluoroquinolone-resistant isolates. Methods: The PubMed, Scopus, Embase, and Web of Science databases were carefully searched until August 6, 2022, for relevant papers. The number of resistant isolates and sample size were used to estimate the proportion of resistant isolates, fitting a model with random effects, and DerSimonian-Laird estimated heterogeneity. Furthermore, meta-regression and subgroup analyses were used to assess the moderators to identify the sources of heterogeneity. Meta-analysis was performed using R software. Results: Forty-seven studies evaluated fluoroquinolone resistance in Brucella spp. Isolates. Fluoroquinolones have shown high in vitro efficacy against Brucella spp. The resistance rates to ofloxacin, sparfloxacin, fleroxacin, pefloxacin, and lomefloxacin were 2%, 1.6%, and 4.6%, respectively. Conclusion: Clinical in vitro tests demonstrated that fluoroquinolones can eradicate Brucella spp. Owing to first-line medication resistance, recurrence, and toxicity, it is essential to standardize the Brucella antimicrobial susceptibility test method for a more precise screening of resistance status. Fluoroquinolones are less resistant to fluoroquinolone-based treatments in modern clinical practice as alternatives to standard therapy for patients with brucellosis relapse after treatment with another regimen and in patients who have developed toxicity from older agents.

Is Brucella excreted in cattle faeces? - Evidence from Punjab, India.

Brucellosis is a neglected zoonosis that affects animals and people in much of the underdeveloped world. The disease is endemic in cattle in Punjab, India and controlling it is a public health challenge. Dairy farmers and farm labour commonly handle cattle faeces with bare hands and personal protective equipments are not used. No studies have been conducted about the shedding of Brucella species in faeces of sero positive cattle in the state. This study aimed to isolate and identify the Brucella species from faeces of sero positive cattle in Punjab, India. Faecal samples were collected from 350 Brucella sero positive cattle in Ludhiana district of Punjab, India. Isolation was performed using a pre-enriched Brucella selective broth medium as well as Brucella selective medium agar plates containing horse serum and Brucella selective supplements. Isolates were identified using Gram staining technique and rapid slide agglutination test, and then confirmed by using bcsp31 and 16s rRNA genus specific PCR. Isolates were further identified up to species level by using Bruce-Ladder multiplex PCR. Fourteen Brucella species were isolated, all of which showed coccobacilli on gram staining, positive rapid slide agglutination test and amplification of bcsp31 and 16s rRNA genes. Of the 14 isolates, 11 were identified as Brucella abortus and 3 were identified as Brucella melitensis. The study demonstrates that animal faeces could pose a potential risk for animal and human health and faeces of seropositive cattle must be handled with care.

Fulminant endogenous endophthalmitis caused by Brucella melitensis, a case report.

Key Clinical Message: Ocular brucellosis is a potential cause of endogenous endophthalmitis in endemic areas, which can be associated with sight-threatening complications. Abstract: To report a patient with unusual fulminant endogenous endophthalmitis due to Brucella melitensis. A 25-year-old woman with a history of fever and right shoulder pain from 4 months ago and a positive Wright test presented with acute panuveitis in her right eye. All laboratory tests were unremarkable except for the positive polymerase chain reaction (PCR) test of the vitreous sample for B. melitensis. Despite the therapeutic efforts, including multiple vitreoretinal surgeries, and intravitreal and systemic antibiotics, the patient's final follow-up examination after 6 months revealed hand motion vision, hypotonia, and pre-phthisis bulbi status. The fellow eye was entirely normal. Brucella endogenous endophthalmitis can be fulminant and result in poor visual outcomes. It is suggested to consider ocular brucellosis as a potential cause of endogenous endophthalmitis in endemic areas.

Detection of Virulence-Associated Genes among Brucella melitensis and Brucella abortus Clinical Isolates in Greece, 2001-2022.

Brucellosis remains an important zoonotic disease in several parts of the world; in Greece, although it is declining, it is still endemic, affecting both the financial and public health sectors. The current study was undertaken to investigate the presence and distribution of virulence-associated genes among Brucella spp. clinical strains isolated during 2001-2022. Species identification was performed using conventional methodology and Bruce-ladder PCR. The presence of the virulence genes mviN, manA, wbkA, perA, omp19, ure, cbg and virB was investigated using PCR. During the study period, a total of 334 Brucella isolates were identified, of which 328 (98.2%) were detected from positive blood cultures; 315 (94.3%) of the isolates were identified as B. melitensis, whilst the remaining 16 (4.8%) and 3 (0.9%) were identified as B. abortus and B. suis, respectively. Notably, two of the B. melitensis were assigned to the REV-1 vaccine strain type. The presence of the omp19, manA, mviN and perA genes was confirmed in all 315 B. melitensis isolates, while ure, wbkA, cbg and virB genes were detected in all but 9, 2, 1 and 1 of the isolates, respectively. All eight virulence genes were amplified in all B. abortus and B. suis isolates. The detection rate of virulence genes did not differ significantly among species. In conclusion, brucellosis is still considered a prevailing zoonotic disease in Greece, with the majority of the isolates identified as B. melitensis. The eight pathogenicity-associated genes were present in almost all Brucella isolates, although the ure gene was absent from a limited number of B. melitensis isolates.