Seroprevalence and risk factors for brucellosis amongst livestock and humans in a multi-herd ranch system in Kagera, Tanzania.

Background: Brucellosis remains a significant health and economic challenge for livestock and humans globally. Despite its public health implications, the factors driving the endemic persistence of at the human-livestock interface in Tanzania remain poorly elucidated. This study aimed to identify the seroprevalence of infection in livestock and humans within a ranching system and determine associated risk factors for disease endemicity.

Modelling the control of bovine brucellosis in India.

Brucellosis imposes substantial impacts on livestock production and public health worldwide. A stochastic, age-structured model incorporating herd demographics was developed describing within- and between-herd transmission of in dairy cattle herds. The model was fitted to data from a cross-sectional study conducted in Punjab State of India and used to evaluate the effectiveness of control strategies under consideration.

Development of a Multiplex Bead Assay to Detect Serological Responses to Species in Domestic Pigs and Wild Boar with the Potential to Overcome Cross-Reactivity with O:9.

The aim of this study was to develop a multiplex bead assay using a rLPS antigen, a smooth antigen, and a O:9 antigen that not only discriminates -infected from -uninfected pigs and wild boar, but also overcomes the cross reactivity with O:9. Sera from 126 domestic pigs were tested: 29 pigs were infected, 80 were non-infected and 17 were confirmed to be false positive serological reactors (FPSR). Sera from 49 wild boar were tested: 18 were positive and 31 were negative.

The Tip of O-Polysaccharide Is a Potent Epitope in Response to Brucellosis Infection and Enables Short Synthetic Antigens to Be Superior Diagnostic Reagents.

Brucellosis is a global disease and the world's most prevalent zoonosis. All cases in livestock and most cases in humans are caused by members of the genus that possess a surface O-polysaccharide (OPS) comprised of a rare monosaccharide 4-deoxy-4-formamido-D-mannopyranose assembled with α1,2 and α1,3 linkages. The OPS of the bacterium is the basis for serodiagnostic tests for brucellosis.

Brucella Seroprevalence and Associated Risk Factors in Occupationally Exposed Humans in Selected Districts of Southern Province, Zambia.

Brucellosis is a neglected debilitating zoonosis widely recognized as an occupational health hazard. The seroprevalence of human anti- antibodies in high-risk populations, as well as their risk factors, have not been well-documented in Zambia. This study aimed at estimating the seroprevalence in herdsmen and abattoir workers and assess the associated risk factors.

Performance characteristics and costs of serological tests for brucellosis in a pastoralist community of northern Tanzania.

The control of brucellosis across sub-Saharan Africa is hampered by the lack of standardized testing and the use of tests with poor performance. This study evaluated the performance and costs of serological assays for human brucellosis in a pastoralist community in northern Tanzania. Serum collected from 218 febrile hospital patients was used to evaluate the performance of seven index tests, selected based on international recommendation or current use.

Prevalence and speciation of brucellosis in febrile patients from a pastoralist community of Tanzania.

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.

Evaluation of the English bovine brucellosis surveillance system considering probability of disease introduction and non-random sampling.

The English surveillance system for bovine brucellosis was evaluated. The confidence in detecting at least one infected herd in the local population (surveillance system sensitivity or SSe), and the confidence in freedom from disease (PFree) adjusted (PFreeAdj) for the probability of disease introduction from abroad by imported animals (PIntro), were estimated for quarterly surveillance periods of 2016; because dairy herds were tested quarterly on bulk tank milk (BTM) with an antibody indirect ELISA. A stochastic model was developed and six surveillance components (representing also the local population strata), were evaluated.

Brucellosis in dairy herds: A public health concern in the milk supply chains of West and Central Africa.

Ten herd-level cross-sectional studies were conducted in peri-urban dairy production areas of seven West and Central African countries (Burkina Faso, Burundi, Cameroon, Mali, Niger, Senegal and Togo). The objectives were to estimate herd level Brucella spp. seroprevalence and identify risk factors for seropositivity.

Rapid Veterinary Diagnosis of Bovine Reproductive Infectious Diseases from Semen Using Paper-Origami DNA Microfluidics.

The health and well-being of cattle is an important issue in maintaining and increasing global agricultural output. In dairy production within low and middle income countries (LMICs), there is a significant biosensing challenge in detecting sexually transmitted infection (STI) pathogens during animal husbandry, due in part to difficulties associated with the limited infrastructure for veterinary medicine. Here we demonstrate low-cost, multiplexed, and sample-to-answer paper-origami tests for the detection of three bovine infectious reproductive diseases in semen samples, collected at a test site in rural India.

Brucellosis: Improved Diagnostics and Vaccine Insights from Synthetic Glycans.

Brucellosis is a serious zoonotic bacterial disease that is ranked by the World Health Organization among the top seven "neglected zoonoses" that threaten human health and cause poverty. It is a costly, highly contagious disease that affects ruminants, cattle, sheep, goats, and other productive animals such as pigs. Symptoms include abortions, infertility, decreased milk production, weight loss, and lameness.

Novel Solutions for Vaccines and Diagnostics To Combat Brucellosis.

Brucellosis is diagnosed by detection of antibodies in the blood of animals and humans that are specific for two carbohydrate antigens, termed A and M, which are present concurrently in a single cell wall O-polysaccharide. Animal brucellosis vaccines contain these antigenic determinants, and consequently infected and vaccinated animals cannot be differentiated as both groups produce A and M specific antibodies. We hypothesized that chemical synthesis of a pure A vaccine would offer unique identification of infected animals by a synthetic M diagnostic antigen that would not react with antibodies generated by this vaccine.

The quest for a true One Health perspective of brucellosis.

One Health is an interdisciplinary collaboration that aims at mitigating risks to human health arising from microorganisms present in non-human animal species, which have the potential to be transmitted and cause disease in humans. Different degrees of scientific collaboration and sectoral integration are needed for different types of zoonotic diseases, depending on the health and associated economic gains that can be expected from a One Health approach. Indeed, mitigating zoonotic risks related to emerging diseases with pandemic potential is different from mitigating risks related to endemic zoonotic diseases like brucellosis.

Improved serodiagnosis of bovine brucellosis by novel synthetic oligosaccharide antigens representing the capping m epitope elements of Brucella O-polysaccharide.

Members of the genus Brucella have cell wall characteristics of Gram-negative bacteria, which in the most significant species includes O-polysaccharide (OPS). Serology is the most cost-effective means of detecting brucellosis, as infection with smooth strains of Brucella leads to the induction of high antibody titers against the OPS, an unbranched homopolymer of 4,6-dideoxy-4-formamido-D-mannopyranosyl residues (D-Rha4NFo) that are variably α(1→2)- and α(1→3)-linked. Six d-Rha4NFo homo-oligosaccharides were synthesized, each containing a single α(1→3) link but with a varied number of α(1→2) links.

Molecular recognition of Brucella A and M antigens dissected by synthetic oligosaccharide glycoconjugates leads to a disaccharide diagnostic for brucellosis.

The cell wall O-polysaccharides of pathogenic Brucella species are homopolymers of the rare sugar 4,6-dideoxy-4-formamido-α-D-mannopyranose. Despite the apparent simplicity of the polysaccharide it appears to be a "block copolymer" composed of A and M polysaccharide sequences expressed as a single molecule. The simultaneous presence of both in the cell wall has complicated the understanding of the molecular recognition of these antigens by antibodies present in the serum of infected animals and humans and by monoclonal antibodies.

Investigating the use of protein saver cards for storage and subsequent detection of bovine anti-Brucella abortus smooth lipopolysaccharide antibodies and gamma interferon.

Brucella abortus, a smooth strain of the genus Brucella, is the causative agent of bovine brucellosis. To support the ongoing development of diagnostic tests for bovine brucellosis, the use of Protein Saver cards (Whatman) for bovine blood serum and plasma sample collection has been evaluated. These cards offer significant logistical and safety alternatives to transporting and storing liquid samples and may aid in diagnostic programs and validation studies.

New developments in the immunodiagnosis of brucellosis in livestock and wildlife.

Although relatively effective diagnostic tests for brucellosis have been in existence for more than 100 years, it remains a serious, embedded and also a re-emerging disease in many parts of the globe. There are many factors besides suboptimal diagnosis that impede the complete and sustained eradication of animal brucellosis. In this review a case for the continued improvement of diagnostic methods is made through identifying existing shortcomings and considering what impact these have upon control and eradication.

An evaluation of the capability of existing and novel serodiagnostic methods for porcine brucellosis to reduce false positive serological reactions.

Porcine brucellosis is a zoonotic disease of truly global significance because even in countries without the disease the occurrence of false positive serological reactions (FPSRs) creates significant problems. Statutory diagnostic testing is required in many disease free countries or regions and is often a prerequisite for the movement of live animals. Currently this testing is dependent almost entirely on serological assays and these may result in a significant number of FPSRs.

The first International Standard anti-Brucella melitensis Serum.

The World Organisation for Animal Health (OIE) requested an International Standard anti-Brucella melitensis Serum (ISaBmS) to standardise diagnostic tests and reagents for sheep and goats. The agreed criteria were the highest dilution (in negative serum) of the standard which must give a positive result and the lowest dilution (in negative serum) which must simultaneously give a negative result. The two dilutions for each assay were, respectively: indirect enzyme-linked immunosorbent assay (iELISA) 1/64 and 1/750, competitive ELISA (cELISA) 1/8 and 1/300, fluorescent polarisation assay (FPA) 1/16 and 1/200, Rose Bengal test (RBT) 1/16 and 1/200.

Evaluation of competitive ELISA for detection of antibodies to Brucella infection in domestic animals.

Aim: To evaluate competitive enzyme-linked immunosorbent assay (cELISA) for its suitability as an additional serological test for the diagnosis of animal brucellosis.

Methods: cELISA, which was developed at the Veterinary Laboratories Agency, has been evaluated for its accuracy and suitability as an additional serological test for the diagnosis of animal brucellosis. Samples from naturally and experimentally infected animals and those from Brucella-free flocks and herds were tested.