OBJECTIVE: This study aimed to identify the relationship between bovine brucellosis prevalence, farmers\' knowledge, attitude, practice (KAP), and social factors on migratory draft cattle and smallholder dairy farms in the central dry zone of Myanmar.
METHODS: This cross-sectional study was conducted on 54 migratory and 38 dairy cattle farms between August 2020 and February 2021. A structured questionnaire was used to identify farmers\' behaviors. Bulk milk was sampled and tested using indirect enzyme-linked immunosorbent assay (I-ELISA). STATA 17 was used for all the analyses.
RESULTS: Migratory cattle farms had a higher farm level brucellosis prevalence (14.8%) than dairy farms (2.6%; χ2 = 3.75; df = 1; p = 0.05). Only 2.8% of the farmers had knowledge about brucellosis, while 39.1% and 41.6% had attitudes and farm practices with respect to brucellosis, respectively in the study area. Socio-economic attribute of training in animal husbandry (p<0.01), raising system (p<0.01), practice of separating the aborted cow (p<0.01) were negatively associated to brucellosis. The overall farm level brucellosis prevalence was strongly associated with cattle herd size (p = 0.01), free movement grazing practices (p<0.01), practice of self-removal of placental debris without using personal protective equipment (p<0.01) and farmers\' attitudes towards eating cow placenta debris (p<0.01).
CONCLUSIONS: Farmers had little knowledge of brucellosis. Attitudes and practices differed significantly between migratory and dairy farmers. Training and extension programs are necessary to make farmers aware of their KAP situation since livestock migration and the custom of eating cow placental debris contribute to the spread of brucellosis. Persistent efforts are required to reduce the adverse effects of brucellosis. Therefore, the study suggests that a feasible control intervention and public awareness campaigns need to be conducted regarding methods of preventing human exposure to brucellosis.

Bovine brucellosis, primarily caused by Brucella abortus, severely affects both animal health and human well-being. Accurate diagnosis is crucial for designing informed control and prevention measures. Lacking a gold standard test makes it challenging to determine optimal cut-off values and evaluate the diagnostic performance of tests. In this study, we developed a novel Bayesian Latent Class Model that integrates both binary and continuous testing outcomes, incorporating additional fixed (parity) and random (farm) effects, to calibrate optimal cut-off values by maximizing Youden Index. We tested 651 serum samples collected from six dairy farms in two regions of Henan Province, China with four serological tests: Rose Bengal Test, Serum Agglutination Test, Fluorescence Polarization Assay, and Competitive Enzyme-Linked Immunosorbent Assay. Our analysis revealed that the optimal cut-off values for FPA and C-ELISA were 94.2 mP and 0.403 PI, respectively. Sensitivity estimates for the four tests ranged from 69.7% to 89.9%, while specificity estimates varied between 97.1% and 99.6%. The true prevalences in the two study regions in Henan province were 4.7% and 30.3%. Parity-specific odds ratios for positive serological status ranged from 1.2 to 2.2 for different parity groups compared to primiparous cows. This approach provides a robust framework for validating diagnostic tests for both continuous and discrete tests in the absence of a gold standard test. Our findings can enhance our ability to design targeted disease detection strategies and implement effective control measures for brucellosis in Chinese dairy farms.

Bovine brucellosis diagnosis is a major problem to be solved; the disease has a tremendous economic impact with significant losses in meat and dairy products, besides the fact that it can be transmitted to humans. The sanitary measures instituted in Brazil are based on disease control through diagnosis, animal sacrifice, and vaccination. Although the currently available diagnostic tests show suitable quality parameters, they are time-consuming, and the incidence of false-positive and/or false-negative results is still observed, hindering effective disease control. The development of a low-cost, fast, and accurate brucellosis diagnosis test remains a need for proper sanitary measures at a large-scale analysis. In this context, spectroscopy techniques associated with machine learning tools have shown great potential for use in diagnostic tests. In this study, bovine blood serum was investigated by UV-vis spectroscopy and machine learning algorithms to build a prediction model for Brucella abortus diagnosis. Here we first pre-treated the UV raw data by using Standard Normal Deviate method to remove baseline deviation, then apply principal component analysis - a clustering method - to observe the group formation tendency; the first results showed no clustering tendency with a messy sample score distribution, then we properly select the main principal components to improve clusterization. Finally, by using machine learning algorithms (SVM and KNN), the predicting models achieved a 92.5% overall accuracy. The present methodology provides a test result in an average time of 5 min, while the standard diagnosis, with the screening and confirmatory tests, can take up to 48 h. The present result demonstrates the method\'s viability for diagnosing bovine brucellosis, which can significantly contribute to disease control programs in Brazil and other countries.

From 2001, due to the launching of the National Program for the Control and Eradication of Brucellosis and Tuberculosis, Brazil began a series of studies aimed at the epidemiological characterization of bovine brucellosis in its federative units. In the state of Mato Grosso, studies conducted in 2003 and 2014 showed a reduction in the prevalence of infected herds from 41.2 % to 24 % and in the prevalence of seropositive animals from 10.2 % to 5.1 %. These results stemmed from the efficient heifer vaccination program with S19 implemented by the state. From this scenario, the present study quantified and compared the benefits and costs of bovine brucellosis control in the state through a financial analysis. When considering private and public costs, the Net Present Value (NPV) was estimated at US$ 37.5 million, the Internal Rate of Return (IRR) was calculated at 31 %, and the Benefit-Cost Ratio (BCR) was 2.3. When considering only the private costs, the NPV was US$ 51.3 million, the IRR was 46 % and the BCR was 3.43, indicating that the cattle producer in Mato Grosso had a return of US$ 3.43 for each US$ 1.00 invested. Therefore, the bovine brucellosis control actions carried out in the state of Mato Grosso between 2003 and 2014 were highly advantageous from the economic point of view. The most rational way to continue decreasing bovine brucellosis prevalences at low cost in the state is to maintain the heifer vaccination program, using the RB51 vaccine in addition to S19.

Bovine brucellosis, mainly caused by Brucella abortus, is a worldwide distribution anthropozoonosis that causes great economic losses. In 2001, Brazil launched the National Program for the Control and Eradication of Brucellosis and Tuberculosis (PNCEBT). Contemporaneously, a great effort to characterize the epidemiology of the disease in Brazilian states was started. In the state of Rondônia, a first epidemiological study was carried out in 2004, revealing a prevalence of 35.2% of infected herds and 6.22% of seropositive females. In 2014, after a successful heifer vaccination program with strain 19 (S19), a second study detected a reduction in the prevalence of infected herds to 12.3% and of seropositive females to 1.9%. The present study aimed to quantify and compare the costs and benefits related to the control of bovine brucellosis in the state through an accounting analysis. Vaccinating heifers and performing serological tests to move animals were computed as private costs. The expenditures of the state official veterinary service for brucellosis control were considered public cost. The considered benefits of lowering prevalence were decreased cow replacement, decreased abortions, decreased perinatal and cow mortality, and increased milk production. Considering private and public costs, the net present value (NPV) was estimated at US$ 18.3 million, the internal rate of return (IRR) was calculated at 23%, and the benefit-cost ratio (BCR) was 1.7. When considering only the private costs, the NPV was US$34.9 million, the IRR was 49%, and the BCR was 3.0, meaning that the bovine producer had a return of 3 for each unit of currency invested. The results showed that the bovine brucellosis control measures implemented in the state of Rondônia, which had as its main strategy the vaccination of heifers with S19, produced highly advantageous economic results. The state should continue with its vaccination program, stimulating the use of the RB51 vaccine in addition to S19, to achieve further reductions in prevalence at low cost.

Brucellosis in cattle herds has caused severe economic losses in many regions worldwide. A cross-sectional study was performed to investigate the presence of Brucella spp. in industrial dairy cattle farms in Iran. For this purpose, 935 blood and 935 milk samples were randomly collected from industrial dairy cattle farms in Iran\'s Alborz and Tehran provinces. Blood and milk samples were collected on the same day from each cow. Serological, bacteriological, and molecular characterization of Brucella isolates were performed using standard methods. Our results revealed the seroprevalence of brucellosis in dairy cattle farms in the Alborz and Tehran provinces, reaching 19.8%, 6.7%, 5.1%, 14.1%, and 13.1% using the Rose Bengal plate test (RBPT), serum agglutination test (SAT), 2-mercaptoethanol test (2-ME), indirect enzyme-linked immunosorbent assay (i-ELISA) and milk ring test (MRT), respectively. Furthermore, the results of bacterial culture and PCR analyses showed the presence of Brucella abortus among dairy cattle in the Alborz province and Brucella melitensis and B. abortus among dairy cattle in the Tehran province. Moreover, statistical analysis with Cohen\'s Kappa has highlighted the near-perfect agreement between RBPT and i-ELISA (k = 0.86). In contrast, substantial agreement was shown between RBPT and SAT performance (k = 0.70) and moderate agreement between RBPT and 2-ME (k = 0.67). The findings of this investigation showed shedding of Brucella in the milk of seropositive cows, which is a serious problem involving the maintenance and further spread of Brucella infection on the farm. Therefore, for brucellosis detection or eradication in dairy cattle farms, bacteriological and serological tests of milk samples should be performed along with blood analysis to inhibit the uncontrolled spread of the disease in animals and humans.

The study was carried out on six villages in northern Egypt to evaluate the epidemiological situation of bovine brucellosis among 989 unvaccinated household cattle by Rose Bengal Plate Test (RBPT) and indirect ELISA (iELISA) and to investigate the existence of Brucella DNA using real-time PCR in 100 milk and 100 sera from seropositive cattle and 50 sera from seronegative cattle. The overall seroprevalence was 20.7% and 23.7% by RBPT and iELISA, respectively. Based on the iELISA results, the seroprevalence was significantly (P < 0.05) higher in the village II (34.7%) and cattle > 7 years (30.1%). More males than females were non-significant seropositive (P = 0.6). There was 95% agreement between RBPT and iELISA, although iELISA showed a higher positivity rate (23.7%, 95% CI: 0.21-0.26) than RBPT (20.7%, 95% CI: 0.18-0.24). DNA of Brucella was confirmed in 16 milk samples by IS711 qPCR from seropositive cattle, however, no Brucella DNA was detected in serum samples tested positive and negative. Brucella abortus was the only species detected based on the alkB gene. Prevalence is highly related to the sampling site and the age of the animals. In conclusion, although qPCR is more accurate and commonly used in the diagnosis of most infectious diseases but in this situation iELISA is preferred and recommended for continuous screening and animal movement restriction and vaccination protocols, especially in high-risk areas.

UNASSIGNED: Brucellosis is a contagious, economically significant bacterial disease that affects animals worldwide and is one of the most neglected zoonotic diseases in the world. The disease poses a barrier to the trade of animals and animal products, represents a public health hazard, and is an impediment to free animal movement.
UNASSIGNED: A cross-sectional study was carried out from December 2019 to May 2020 in order to determine seroprevalence and identify potential risk factors for brucellosis in dairy cows in the Central Highlands of Ethiopia with recent cases of abortion. Purposive sampling was carried out on the farms and kebeles in question to screen for recent cases of abortion in dairy cows. For the purpose of performing serological testing, 352 blood samples from dairy cattle were obtained. The Rose Bengal Plate test was used to initially screen the serum samples, and the Complement Fixation test was utilized as a confirmatory test.
UNASSIGNED: Using combined RBPT and CFT tests, the overall seroprevalence of bovine brucellosis was 0.6% (95% CI: 0.16-2.09). Retained fetal membrane (OR = 32.74, p = 0.006), market-based stock replacement (OR = 16.55, p = 0.002), breeding method (OR = 7.58, p = 0.027), and late stage of abortion (OR = 14.74, p = 0.0002) are all significantly associated risk factors.
UNASSIGNED: The present seroprevalence study revealed that brucellosis is prevalent at a lower rate among dairy cattle in the study areas. However, there is a possible risk of brucellosis transmission in dairy cattle and the exposed human population in research locations because no control measures were put in place there. Implementing a test and slaughter method with compensation for farmers is advised due to the low prevalence of bovine brucellosis in government-owned and small-holder farms.

Brucella abortus (B. abortus) as an important infectious agent of bovine brucellosis cannot be ignored, especially in countries/regions dominated by animal husbandry. Thus, the development of an ultrasensitive and highly specific identification technique is an ideal strategy to control the transmission of bovine brucellosis. In this report, a novel detection protocol, which utilizes multiple cross displacement amplification (MCDA) combined with a gold nanoparticles-based lateral flow biosensor (AuNPs-LFB) targeting the BruAb2_0168 gene was successfully devised and established for the identification of B. abortus (termed B. abortus-MCDA-LFB). Ten specific primers containing engineered C1-FAM (carboxyfluorescein) and D1-biotin primers were designed according to the MCDA reaction mechanism. These genomic DNA extracted from various bacterial strains and whole blood samples were used to optimize and evaluate the B. abortus-MCDA-LFB assay. As a result, the optimal reaction conditions for the B. abortus-MCDA-LFB assay were 66°C for 40 min. The limit of detection of the B. abortus-MCDA-LFB was 10 fg/μl (~3 copies/μl) for genomic DNA extracted from pure cultures of B. abortus isolate. Meanwhile, the B. abortus-MCDA-LFB assay accurately identified all tested B. abortus strains, and there was no cross-reaction with non-B. abortus pathogens. Moreover, the detection workflow of the B. abortus-MCDA-LFB assay for whole blood samples can be completed within 70 min, and the cost of a single test is approximately 5.0 USD. Taken together, the B. abortus-MCDA-LFB assay is a visual, fast, ultrasensitive, low-cost, easy-to-operate, and highly specific detection method, which can be used as a rapid identification tool for B. abortus infections.

[This corrects the article DOI: 10.1016/j.nmni.2022.100975.].