Accuracy of serological tests for bovine brucellosis: A systematic review and meta-analysis.

The direct methods for diagnosis of bovine brucellosis have several limitations, therefore serological tests are the basis for the diagnosis of the disease. However, a meta-analysis estimating the diagnostic sensitivity (DSe) and diagnostic specificity (DSp) on the main tests used in bovine brucellosis control programs worldwide has not been performed. This systematic review and meta-analysis aimed to estimate the DSe, DSp and thereby accuracy of serological tests individually used in the diagnosis of bovine brucellosis. The databases CABI, Cochrane Library, PubMed/MEDLINE, SciELO, Scopus and Web of Science were used to select articles. The search resulted in 5308 studies, of which 71 were selected for systematic review using quality assessment tools and 65 studies were included in the meta-analysis. For the meta-analysis, 178 assays and 11 different serological tests were considered. To estimate DSe and DSp of the tests, studies were divided according to animal selection for the studies: (1) studies that carried out a random or consecutive selection of participants (noncasecontrol studies) and (2) all studies, including casecontrol studies. Considering only the non-case-control studies to estimate the DSe, the tests that exhibited the best and worst performance were the iELISA test (indirect enzyme immunoassay - bacterial suspension as antigen - BS) (96.5%, 95% CI: 94.1-97.9%) and 2ME (2- mercaptoethanol test) (85.0%, 95% CI: 79.6-89.1%), respectively; while for DSp, the FPA (fluorescence polarization assay) (99, 7%, 95% CI: 99.5-99.8%) and PCFIA tests (protein concentration fluorescence immunoassay) (78.5%, 95% CI: 70.0-85.1%) showed better and worse performance, respectively. Overall, our results showed an overestimation in the DSe and DSp of the eleven serological tests assessed when casecontrol studies were included in the meta-analysis, which is a concern considering its impacts on the time and costs associated with populational diagnosis of the diseases, since several of these tests are routinely used in the control and eradication programs of bovine brucellosis worldwide. Furthermore, the tests that exhibited the best DSe and DSp, iELISA (BS) and FPA, respectively, are relatively easy to perform and interpret and the test which showed the best overall accuracy was FPA.

Turning chaotic sample group clusterization into organized ones by feature selection: Application on photodiagnosis of Brucella abortus serological test.

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.

Levantamento sorológico de brucelose em bovinos monitorados no estado da Bahia / Serological survey of brucellosis in cattle monitored in the estate of Bahia

A brucelose é uma doença bacteriana de grande importância para a economia pecuária e para a saúde pública por se tratar de uma zoonose. É uma doença infecto-contagiosa que tem com agente etiológico bactérias do gênero Brucella. Em bovinos, as espécies do gênero é a Brucella abortus, que são cocobacilos gram negativo, intracelulares facultativos, imóveis e não esporulado. A infecção apresenta evolução crônica e acomete animais de todas as idades, sendo mais frequente em indivíduos sexualmente maduros. O objetivo desse trabalho é investigar, por meio da sorologia para brucelose bovina, utilizando a técnica do ELISA indireto, amostras de animais reagentes abatidos em frigoríficos inspecionados no estado da Bahia. Foram utilizados 666 animais, selecionados aleatoriamente no momento do abate. O sangue foi coletado com finalidade de obtenção de soro, todas as amostras foram submetidas à prova de triagem do Antígeno Acidificado Tamponado (AAT), prova do 2mercaptoetanol (2-ME) e ELISA Indireto. Das amostras reagentes no teste do AAT, obteve-se uma prevalência estimada em 1,2%. A prevalência no teste do ELISA foi de 13,21% (n=86). Esse resultado sugere a ocorrência de falsos negativos quando se utiliza a prova do antígeno acidificado tamponado.

Brucellosis is a bacterial disease of great importance to the livestock economy and to public health because it is a zoonosis. It is an infectious disease that has etiologic agent with bacteria of the genus Brucella. In cattle, the species of the genus Brucella is Brucella abortus that are gram negative, facultative intracellular, real estate and not sporulated. The infection presents chronic and affects animals of all ages, being more frequent in sexually mature individuals. This study aimed to investigate through serology for brucellosis, using the technique of indirect ELISA, samples from positive animals slaughtered in slaughterhouses inspected in the state of Bahia. A total of 666 animals were used, randomly selected at the time of slaughter. Blood was collected in order to obtain serum, all samples were subjected to a screening test Antigen Buffered Acidified (AAT), proof of 2-mercaptoethanol (2-ME) and Indirect ELISA. Of reagents in the test samples of AAT obtained an estimated prevalence of 1.2%. The prevalence in the ELISA test was 13.21% (n = 86). This result suggests the occurrence of false negatives when using the buffered acidified antigen test.

Development of a novel glycoprotein-based immunochromatographic test for the rapid serodiagnosis of bovine brucellosis.

AIMS: Bovine brucellosis is a worldwide zoonotic disease that causes important economic losses and public health concerns. Because control of the disease depends on vaccination, serodiagnosis and isolation of the infected animals, affordable, rapid and accurate point of care (POC) tests are needed. METHODS AND RESULTS: We developed and evaluated a novel glycoprotein-based immunochromatographic test for the detection of IgG antibodies against the O-polysaccharide of Brucella in bovine serum samples. Brucella GlycoStrip combines the power of immunochromatographic and bacterial glycoengineering technologies for the diagnosis of bovine brucellosis. The analysis of positive and negative reference samples indicated that the test has a diagnostic sensitivity and specificity of 96.9% (95% CI: 92.7%-100.0%) and 100%, respectively. CONCLUSIONS: Due to the recombinant glycoprotein-based antigen OAg-AcrA, which consists of the O-side chain of Brucella smooth lipopolysaccharide (sLPS) covalently linked to the carrier protein AcrA, the test is highly accurate, allows the differentiation of infected animals from those vaccinated with a rough strain or with a single dose of a smooth strain and fulfil the minimum diagnostic requirements established by the national and international regulations. SIGNIFICANCE AND IMPACT OF STUDY: This strip test could provide a rapid (10 min) and accurate diagnosis of bovine brucellosis in the field contributing to the control of the disease.

Evaluation of diagnostic tests' sensitivity, specificity and predictive values in bovine carcasses showing brucellosis suggestive lesions, condemned by Brazilian Federal Meat Inspection Service in the Amazon Region of Brazil.

Cervical bursitis is a suggestive lesion of bovine brucellosis. Diagnostic sensitivity and specificity of two brucellosis serological tests, Rose Bengal (RB) and serum agglutination test with 2-mercaptoethanol (SAT/2-ME), and of isolation and identification (bacteriology) were evaluated through Bayesian latent class analysis (BLCA). A total of 165 paired serum and cervical bursitis samples detected at inspection by Brazilian federal meat inspection services were analyzed. The best model fit to the data occurred when accounting for the conditional dependence between serological tests. According to this model, RB and SAT/2-ME had almost the same sensitivity, 0.960 [0.903 - 0.992] and 0.963 [0.906 - 0.994] with 95 % Credible Interval (95 %CrI), respectively. Specificities were 0.9068 [0.562 - 0.997] and 0.875 [0.546 - 0.990] for RB and SAT/2-ME, respectively, also with 95 %CrI. Bacteriology had lower sensitivity than serological tests, 0.594 (95 %CrI: [0.525 - 0.794]) and the highest specificity of all evaluated tests, 0.992 (95 %CrI: [0.961-1.00]). Prevalence of infected animals was 0.829 (95 %CrI: [0.700-0.900]). BLCA showed that both RB and SAT/2-ME fitted to the purpose of initial screening the brucellosis suspect in carcasses with cervical bursitis in a reliable way. The results of RB or SAT/2-ME can guide the sanitary actions for brucellosis control and help the implementation of a risk-based surveillance system in the meat production chain. This strategy is especially true in remote areas with large beef cattle herds, raised extensively, where in vivo tests are rarely performed due to logistic and management constraints, as in the Northern region of Brazil.

Cross-sectional study of Brucella spp. using real-time PCR from bovine whole blood in Colombia.

A cross-sectional study was conducted in Colombia to recover Brucella spp. DNA from bovine whole-blood samples through probe-based real-time PCR (qPCR). By an SNP-based assay, vaccine strains were differentiated from field strains. The associated factors were evaluated using logistical regression models. A total of 656 random cows from 40 herds were selected and analyzed using serology and PCR. The qPCR assay detected 9.5% (n = 62/656; 95% CI: 7.3, 12.0) of the animals with Brucella-DNA presence, while the serological test detected a 6.6% (n = 43/656; CI: 4.8, 8.7). 62.5% (n = 25/40; 95% CI: 45.8, 77.3) of positive cases were detected at the herd-level by the qPCR, while only 27.5% (n = 11/40; 95% CI: 14.6, 43.9) were detected by the serological test. All positive samples were identified as field Brucella strains employing the SNP-based assay. In the final regression model at the animal-level, five variables were associated with Brucella-DNA presence: the use of bulls for mating recorded history of reproductive problems, pregnant cows, parlor milking, and cows belonging to farms ≤200 m from the main road. At the herd-level, two variables were associated with Brucella-DNA presence: recorded history of reproductive problems and the use of bulls for mating. Given the fluctuant brucellosis prevalence in endemic areas, updated epidemiological studies are necessary to evaluate the disease dynamic and if established prevention and control measures have been effective or need to be adjusted. The increase in the prevalence of brucellosis in animal reservoirs creates an important risk of transmission in humans.

Brucella abortus S19 GFP-tagged vaccine allows the serological identification of vaccinated cattle.

Bovine brucellosis induces abortion in cows, produces important economic losses, and causes a widely distributed zoonosis. Its eradication was achieved in several countries after sustained vaccination with the live attenuated Brucella abortus S19 vaccine, in combination with the slaughtering of serologically positive animals. S19 induces antibodies against the smooth lipopolysaccharide (S-LPS), making difficult the differentiation of infected from vaccinated bovines. We developed an S19 strain constitutively expressing the green fluorescent protein (S19-GFP) coded in chromosome II. The S19-GFP displays similar biological characteristics and immunogenic and protective efficacies in mice to the parental S19 strain. S19-GFP can be distinguished from S19 and B. abortus field strains by fluorescence and multiplex PCR. Twenty-five heifers were vaccinated withS19-GFP (5×109 CFU) by the subcutaneous or conjunctival routes and some boosted with GFP seven weeks thereafter. Immunized animals were followed up for over three years and tested for anti-S-LPS antibodies by both the Rose Bengal test and a competitive ELISA. Anti-GFP antibodies were detected by an indirect ELISA and Western blotting. In most cases, anti-S-LPS antibodies preceded for several weeks those against GFP. The anti-GFP antibody response was higher in the GFP boosted than in the non-boosted animals. In all cases, the anti-GFP antibodies persisted longer, or at least as long, as those against S-LPS. The drawbacks and potential advantages of using the S19-GFP vaccine for identifying vaccinated animals in infected environments are discussed.

Effect of co-positivity for brucellosis and tuberculosis on milk yield and fertility of Holstein cows.

This study aimed to determine whether cows detected as tuberculosis (bTB) reactors and seropositive to brucellosis (bBR), as well as co-positive to bBR and bTB (bBR-bTB) and with a complete lactation before slaughter, were associated with reduced milk production and fertility. A total of 8068 productive and reproductive records of high-yielding Holstein cows from a single large dairy herd with a high prevalence of bTB and bBR were collected from 2012 to 2015. Lactation derived either from calving (n = 6019) or hormonally induced lactation (n = 2049), and all cows received growth hormone throughout lactation. For cows not induced into lactation, pregnancy rate to first service for healthy cows (C; 26.6%) was higher (P < 0.01) than bBR (15.2%), bTB (15.8%), and bBR-bTB (1.3%) cows. For induced cows, pregnancy rate to first service did not differ significantly among C, bBR, and bTB (14.5-17.3%) cows, but the percentage success of first service was extremely low (1.3%; P < 0.01) in bBR-bTB cows. Services per pregnancy (only pregnant cows) were lowest for C (3.3 ± 2.9; P < 0.01) and highest (6.4 ± 3.4) for bBR-bTB non-induced cows. This variable was lowest for C (2.9 ± 2.5; P < 0.01) and highest for bBR-bTB non-induced cows (6.3 ± 3.1). Pregnancy rate to all services did not differed for C (79.5%), bBR (76.7%), and bTB (75.9%) but was lower (58.9%; P < 0.01) for bBR-bTB non-induced cows. For induced cows this variable was highest for bBR (53.3%) and lowest for bBR-bTB (34.1%; P < 0.01) non-induced cows. 305-d milk production was increased by 4%, and total milk yield by 7% in TB-positive cows compared to that of the negative cows non-induced hormonally into lactation. This study showed the negative impact of the co-positivity for bTB and bBR on the reproductive efficiency of Holstein cows, although positive bTB and bBR tests enhanced milk yield.

Inquérito sorológico de brucelose em machos e fêmeas bovinas em fazendas do Estado de Mato Grosso do Sul / Serological survey of brucellosis in males and females of cattle in the State of Mato Grosso do Sul

Objetivou-se avaliar a ocorrência de animais soro reagentes à brucelose bovina em fazendas localizadas no Estado de Mato Grosso do Sul, por meio de exame sorológico utilizando o Antígeno Acidificado Tamponado (AAT) e discutir as possíveis diferenças entre as soroprevalências de fêmeas e machos. Foram avaliados, a partir do teste de triagem com Antígeno Acidificado Tamponado (AAT), 724 bovinos da raça Nelore, sendo 274 machos e 450 fêmeas, provenientes de oito propriedades com histórico de problemas reprodutivos. O teste foi procedido conforme o protocolo determinado pelo Ministério da Agricultura, Pecuária e Abastecimento (MAPA). Os resultados demonstraram baixa soroprevalência da doença nos bovinos testados, sendo detectada prevalência para a doença de 1,10% nos machos e 2,88% nas fêmeas.Quando se considera o touro isoladamente nos rebanhos, pode-se perceber que a fertilidade é muito mais importante nos machos do que nas fêmeas individualmente, uma vez que os touros podem se acasalar com um número muito maior de fêmeas, seja na monta natural ou na inseminação artificial, demonstrando a importância do inquérito epidemiológico na população geral, principalmente nos machos. A maior frequência da doença foi encontrada nas fêmeas podendo estar relacionada à infecção por Brucella spp. no ambiente decorrente de parto ou aborto tornando as fêmeas transmissoras permanentes da doença.

The objective of this study was to evaluate the occurrence of seroreactive animals to bovine brucellosis in farms located in the State of Mato Grosso do Sul, by means of a serological examination using the Acidified Buffered Antigen (AAT) and to discuss the possible differences between the seroprevalence of females and males. A total of 724 Nellore cattle, 274 males and 450 females, from eight farms with a history of reproductive problems, were evaluated using the screening test with Acidified Buffered Antigen (AAT). The test was carried out according to the protocol determined by the Ministry of Agriculture, Livestock and Food Supply (MAPA).The results showed a low seroprevalence of the disease in the tested cattle, with a prevalence of 1.10% in males and 2.88% in females.When considered the bull alone in herds, it can be shown that fertility is much more important in males than in females individually, since bulls can mate with a much larger number of females, either in natural mating or in artificial insemination, demonstrating the importance of epidemiological survey in the general population, especially in males. The highest frequency of the disease was found in females and may be related to infection by Brucella spp. in the environment from childbirth or abortion making females permanent transmitters of the disease.

Epidemiological characterization of reported cases of brucellosis in cattle in the Western region of the state of Santa Catarina, Brazil / Caracterização epidemiológica dos casos notificados de brucelose em bovinos na região Oeste do Estado de Santa Catarina, Brasil

Brucellosis is one of the most important and widespread bacterial zoonoses in the world. There are few epidemiological studies on brucellosis in cattle in the productive region of western Santa Catarina. Thus, the objective of this study was to characterize the epidemiological aspects of bovine brucellosis reported in this region from 2013 to 2018. Cattle data were provided by the Integrated Company for Agricultural Development of Santa Catarina (Companhia Integrada de Desenvolvimento Agrícola de Santa Catarina - CIDASC). The prevalence of the disease was evaluated in cattle and herds by means of temporal trend analysis and spatial distribution. Bovines with tests showing positive for brucellosis were analyzed for location (municipality) and year of confirmation of diagnosis. In the study period (2013-2018), 686,086 tests were performed for brucellosis, with a prevalence rate of 1.11% (7,586/686,086). Among the 80,171 herds tested, 0.95% were found to be positive (764/80171). The odds ratio of brucellosis occurrence in cattle increased significantly in 2015 (OR = 1.55) and 2016 (OR = 1.97) and decreased in 2014 (OR = 0.47) and 2017 (OR = 0.97). The disease is present in cattle in 61.07% (80/131) of the municipalities where the tests were performed. Results showed that brucellosis is endemic in the region.(AU)

A brucelose é uma das zoonoses bacterianas mais importantes e difundidas no mundo. São poucos os estudos epidemiológicos sobre a doença em bovinos na região produtiva do Oeste de Santa Catarina. Desta forma, o objetivo deste estudo foi caracterizar os aspectos epidemiológicos da brucelose bovina notificados nesta região entre os anos de 2013 a 2018. Os dados sobre os bovinos foram fornecidos pela Companhia Integrada de Desenvolvimento Agrícola de Santa Catarina (CIDASC). Foram avaliadas as prevalências da doença nos bovinos e rebanhos, por meio de análise de tendência temporal e distribuição espacial. Os bovinos, cujo exame confirmatório mostrou positividade para brucelose, foram analisados quanto à localização (município) e o ano de confirmação do diagnóstico. No período de estudo (2013-2018) foram realizados 686.086 testes para brucelose, encontrando-se prevalência de 1,11% (7.586/686.086) de animais positivos, enquanto a prevalência de rebanhos positivos, dentre os 80.171 testados, foi de 0,95% (764/80171). As razões de chances de ocorrência de brucelose nos bovinos aumentaram significativamente nos anos de 2015 (OR= 1,55) e 2016 (OR= 1,97) e diminuíram em 2014 (OR= 0,47) e 2017 (OR= 0,97). A doença está presente nos bovinos em 61,07% (80/131) dos municípios em que foram realizados os testes. Os resultados demonstram que a brucelose é endêmica na região.(AU)

Immunoproteomics of Brucella abortus reveals potential of recombinant antigens for discriminating vaccinated from naturally infected cattle.

Brucellosis serodiagnosis is still a challenge and vaccination is the main measure used to control bovine brucellosis, being S19 and RB51 the most currently used vaccines. So, in order to contribute to brucellosis control, a bidimensional (2D) immunoblot-based approach was used to find immunogenic proteins to be used in serodiagnosis, particularly with ability to be employed in DIVA (Differentiating Infected from Vaccinated Animals) strategy. Immunoproteomic profile of Brucella abortus 2308 was analyzed in 2D western blotting using pooled sera from S19 vaccinated animals, RB51 vaccinated animals, B. abortus naturally infected animals and non-vaccinated seronegative animals. Evaluation of the antigens differentially immunoreactive against the groups of sera showed three proteins of particular importance: MDH (malate dehydrogenase) immunoreactive for S19-vaccinated animals, SOD (superoxide dismutase) reactive for infected animals and ABC transporter (multispecies sugar ABC transporter) reactive against sera from vaccinated animals (S19 and RB51). These three proteins were produced in E. coli and tested in an indirect ELISA (I-ELISA). For MDH, comparison between the vaccinated animals (independent of the vaccine used) and the seropositive and seronegative animals in I-ELISA showed significant differences. Data on the I-ELISA using SOD showed that sera from non-vaccinated naturally infected animals exhibited significant difference in comparison with all other groups. Otherwise, sera from vaccinated animals (S19 and RB51) and from non-vaccinated naturally infected animals did not show significant difference in OD values, but they were all significant different from non-vaccinated seronegative animals using ABC transporter as antigen in I-ELISA. In conclusion, together the 2D western blot analysis and the preliminary I-ELISA results suggest that the combined use of MDH and SOD could be successful employed in a LPS-free protein based serodiagnosis approach to detect bovine brucellosis and to discriminate vaccinated from naturally infected animals, in early post-vaccination stages.

Bovine Brucellosis: Report of the joint action of the University, Agricultural Defense and the Municipal Health Service in the diagnosis and control of the disease / Brucelose Bovina: Relato da atuação conjunta da Universidade, da Defesa Agropecuária

Bovine Brucellosis is a disease of economic importance and of a zoonotic character, considered of mandatory notification, caused by Brucella abortus, characterized mainly by abortion in the final third of pregnancy and reproductive disorders. The present study reports the joint work of the University, Agricultural Defense and Epidemiological Surveillance in a case of Brucellosis that occurred at the Bovine and Small Ruminant Clinic of the University of São Paulo. A bovine with locomotor disorders was diagnosed with brucellosis when tested together with another animal on the property that had reproductive disorders. The Agricultural Defense was activated and the animal was sent for sanitary slaughter. A joint action was carried out to monitor Brucellosis on the property and notification to the Municipal Health Service. Six animals on the property and three people showed positive results, highlighting the zoonotic potential of the disease and the importance of the veterinarian in controlling it in animals and man.

A Brucelose Bovina é uma doença de importância econômica e de caráter zoonótico, considerada de notificação obrigatória, causada pela Brucella abortus, caracterizada principalmente por abortamento em terço final de gestação e afecções reprodutivas. O presente artigo relata o trabalho conjunto da Universidade, da Defesa Agropecuária e da Vigilância Epidemiológica em um caso de brucelose ocorrido na Clínica de Bovinos e Pequenos Ruminantes da Universidade de São Paulo. Um bovino com afecção locomotora foi diagnosticado com brucelose ao ser testado juntamente com outro animal da propriedade que apresentava afecção reprodutiva. A Defesa Agropecuária foi acionada e o animal foi encaminhado para abate sanitário. Foi realizada ação conjunta para monitoramento da brucelose na propriedade e notificação ao Serviço de Saúde do Município. Seis animais da propriedade e três pessoas apresentaram resultado positivo, ressaltando o potencial zoonótico da doença e a importância do médico veterinário no controle da mesma nos animais e no homem.

Bovine Brucellosis: Report of the joint action of the University, Agricultural Defense and the Municipal Health Service in the diagnosis and control of the disease / Brucelose Bovina: Relato da atuação conjunta da Universidade, da Defesa Agropecuária

Bovine Brucellosis is a disease of economic importance and of a zoonotic character, considered of mandatory notification, caused by Brucella abortus, characterized mainly by abortion in the final third of pregnancy and reproductive disorders. The present study reports the joint work of the University, Agricultural Defense and Epidemiological Surveillance in a case of Brucellosis that occurred at the Bovine and Small Ruminant Clinic of the University of São Paulo. A bovine with locomotor disorders was diagnosed with brucellosis when tested together with another animal on the property that had reproductive disorders. The Agricultural Defense was activated and the animal was sent for sanitary slaughter. A joint action was carried out to monitor Brucellosis on the property and notification to the Municipal Health Service. Six animals on the property and three people showed positive results, highlighting the zoonotic potential of the disease and the importance of the veterinarian in controlling it in animals and man.(AU)

A Brucelose Bovina é uma doença de importância econômica e de caráter zoonótico, considerada de notificação obrigatória, causada pela Brucella abortus, caracterizada principalmente por abortamento em terço final de gestação e afecções reprodutivas. O presente artigo relata o trabalho conjunto da Universidade, da Defesa Agropecuária e da Vigilância Epidemiológica em um caso de brucelose ocorrido na Clínica de Bovinos e Pequenos Ruminantes da Universidade de São Paulo. Um bovino com afecção locomotora foi diagnosticado com brucelose ao ser testado juntamente com outro animal da propriedade que apresentava afecção reprodutiva. A Defesa Agropecuária foi acionada e o animal foi encaminhado para abate sanitário. Foi realizada ação conjunta para monitoramento da brucelose na propriedade e notificação ao Serviço de Saúde do Município. Seis animais da propriedade e três pessoas apresentaram resultado positivo, ressaltando o potencial zoonótico da doença e a importância do médico veterinário no controle da mesma nos animais e no homem.(AU)

Prevalence of bovine brucellosis, paratuberculosis, enzootic leucosis, and antigen-reactive agents to bovine viral diarrhea virus in animals up to one year old / Frequência de brucelose bovina, paratuberculose, leucose enzoótica bovina e antígeno-reagentes para diarreia viral bovina em bovinos com até um ano de idade

Live cattle export is one of the newest commercial sectors available to Brazilian farmers, but to be exported animals must be free of infectious diseases, especially those prohibited by the countries importing them. In this study, 1,800 bovine sera were collected from animals destined for export in the Brazilian states of Goiás (GO), Minas Gerais (MG), and São Paulo (SP). The sera were tested for bovine brucellosis (BB), paratuberculosis (PTB), enzootic bovine leukosis (EBL), and bovine viral diarrhea (BVD). This was the first study in Brazil to conduct a serological survey for bovine PTB in the states of SP, GO, and MG, and the first survey for BVD in GO. The total percentage of animals positive for each disease was 0.33% (2/1,800) for BB, 16.17% (97/1,800) for PTB, 31.50% (189/1,800) for EBL, and 9.67% (58/1,800) for BVD.(AU)

A exportação de bovinos vivos é uma das novas áreas comerciais em que o Brasil está inserido, porém é necessário que os animais sejam livres de doenças infectocontagiosas, principalmente as exigidas pelos países importadores. Os 1800 soros utilizados neste estudo foram de bovinos dos Estados de Goiás (GO), Minas Gerais (MG) e São Paulo (SP), que seriam destinados à exportação. Foram realizados os diagnósticos sorológicos para brucelose bovina (BB), paratuberculose (PTB), leucose enzoótica bovina (EBL) e diarreia viral bovina (BVD), sendo este o primeiro trabalho no Brasil a realizar o levantamento sorológico para PTB em bovinos nos Estados de SP, GO e MG, e de BVD em GO. A porcentagem total de animais positivos para cada uma das patologias foi de 0,33% (2/1800) para BB; 16,17% (97/1800) para PTB; 31,50% (189/ 1800) para EBL e 9,67% (58/1800) para BVD.(AU)

Prevalence of bovine brucellosis, paratuberculosis, enzootic leucosis, and antigen-reactive agents to bovine viral diarrhea virus in animals up to one year old / Frequência de brucelose bovina, paratuberculose, leucose enzoótica bovina e antígeno-reagentes para diarreia viral bovina em bovinos com até um ano de idade

Live cattle export is one of the newest commercial sectors available to Brazilian farmers, but to be exported animals must be free of infectious diseases, especially those prohibited by the countries importing them. In this study, 1,800 bovine sera were collected from animals destined for export in the Brazilian states of Goiás (GO), Minas Gerais (MG), and São Paulo (SP). The sera were tested for bovine brucellosis (BB), paratuberculosis (PTB), enzootic bovine leukosis (EBL), and bovine viral diarrhea (BVD). This was the first study in Brazil to conduct a serological survey for bovine PTB in the states of SP, GO, and MG, and the first survey for BVD in GO. The total percentage of animals positive for each disease was 0.33% (2/1,800) for BB, 16.17% (97/1,800) for PTB, 31.50% (189/1,800) for EBL, and 9.67% (58/1,800) for BVD.

A exportação de bovinos vivos é uma das novas áreas comerciais em que o Brasil está inserido, porém é necessário que os animais sejam livres de doenças infectocontagiosas, principalmente as exigidas pelos países importadores. Os 1800 soros utilizados neste estudo foram de bovinos dos Estados de Goiás (GO), Minas Gerais (MG) e São Paulo (SP), que seriam destinados à exportação. Foram realizados os diagnósticos sorológicos para brucelose bovina (BB), paratuberculose (PTB), leucose enzoótica bovina (EBL) e diarreia viral bovina (BVD), sendo este o primeiro trabalho no Brasil a realizar o levantamento sorológico para PTB em bovinos nos Estados de SP, GO e MG, e de BVD em GO. A porcentagem total de animais positivos para cada uma das patologias foi de 0,33% (2/1800) para BB; 16,17% (97/1800) para PTB; 31,50% (189/ 1800) para EBL e 9,67% (58/1800) para BVD.

Seroconversion attributable to vaccination of heifers with the strain B-19 of Brucella abortus / Soroconversão atribuível à vacinação de bezerras com a cepa B-19 de Brucella abortus

Bovine brucellosis is transmitted by Brucella abortus and causes considerable economic losses to agribusiness. To determine the seroconversion rate attributable to vaccination of heifers with B. abortus strain B-19, 330 blood serum samples from 110 heifers aged three to eight months from five properties in the municipality of Araguaína, Tocantins, Brazil, were analyzed. On day zero (D-0), blood samples were collected, and 55 heifers from the intervention group were vaccinated. The remaining blood samples were collected on days seven (D-7), 14 (D-14), and 21 (D-21). The serum samples were analyzed using the buffered acidified plate antigen (BAPA) test. The rate of seroconversion attributable to vaccination was calculated by subtracting from the seroconversion incidence rate in the intervention group the incidence rate of the control group. On D-0, 100% (110/110) of the heifers were negative in the BAPA test (95% CI [96.70 - 100%], p 0.05) from that of heifers from the intervention group vaccinated on D-7...

A brucelose bovina é causada por Brucella abortus gerando perdas econômicas para a cadeia do agronegócio. Objetivando determinar o coeficiente de soroconversão atribuível à vacinação de bezerras com a cepa B-19 de B. abortus, foram analisadas 330 amostras de soro sanguíneo de 110 bezerras com três a oito meses de idade, provenientes de cinco propriedades do município de Araguaína/TO. O dia zero (D-0) foi marcado pela coleta de sangue dos animais do experimento seguida da vacinação das 55 bezerras do grupo intervenção. As outras coletas de sangue foram realizadas nos dias 7 (D-7), 14 (D-14) e 21 (D-21). As amostras de soro foram submetidas ao teste do antígeno acidificado tamponado (AAT). O coeficiente de soroconversão atribuível à vacinação foi calculado subtraindo-se da incidência de soroconversão no grupo intervenção àquela do grupo controle. No D-0, 100% (110/110) das bezerras amostradas não apresentaram reação ao teste do AAT (IC 95% [96,70% a 100%]; p 0,05) comparada à resposta no D-7 do grupo intervenção...

Seroconversion attributable to vaccination of heifers with the strain B-19 of Brucella abortus / Soroconversão atribuível à vacinação de bezerras com a cepa B-19 de Brucella abortus

Bovine brucellosis is transmitted by Brucella abortus and causes considerable economic losses to agribusiness. To determine the seroconversion rate attributable to vaccination of heifers with B. abortus strain B-19, 330 blood serum samples from 110 heifers aged three to eight months from five properties in the municipality of Araguaína, Tocantins, Brazil, were analyzed. On day zero (D-0), blood samples were collected, and 55 heifers from the intervention group were vaccinated. The remaining blood samples were collected on days seven (D-7), 14 (D-14), and 21 (D-21). The serum samples were analyzed using the buffered acidified plate antigen (BAPA) test. The rate of seroconversion attributable to vaccination was calculated by subtracting from the seroconversion incidence rate in the intervention group the incidence rate of the control group. On D-0, 100% (110/110) of the heifers were negative in the BAPA test (95% CI [96.70 - 100%], p < 0.05). On D-7, the seroconversion rate was 94.55% (52/55) (95% CI [84.88 - 98.84%], p < 0.05) in the intervention group and 0% (0/55) (95% CI [0.00 - 6.49%], p < 0.05) in the control group. On D-14, the rate was 98.18% (54/55) (95% CI [90.28 - 99.95%], p < 0.05) in the intervention group and 0% in the control group. Therefore, seroconversion attributable to vaccination varied from 78.39% (84.88 - 6.49%) to 92.35% (98.86 - 6.49%) on D-7 and from 83.79% (90.28 - 6.49%) to 93.46% (99.95 - 6.49%) on D-14, respectively. On D-21, the seroconversion rate in the 55 heifers from the control group vaccinated on D-14 was 100% (55/55) (95% CI [93.51 - 100%], p < 0.05) but was not significantly different (p > 0.05) from that of heifers from the intervention group vaccinated on D-7...(AU)

A brucelose bovina é causada por Brucella abortus gerando perdas econômicas para a cadeia do agronegócio. Objetivando determinar o coeficiente de soroconversão atribuível à vacinação de bezerras com a cepa B-19 de B. abortus, foram analisadas 330 amostras de soro sanguíneo de 110 bezerras com três a oito meses de idade, provenientes de cinco propriedades do município de Araguaína/TO. O dia zero (D-0) foi marcado pela coleta de sangue dos animais do experimento seguida da vacinação das 55 bezerras do grupo intervenção. As outras coletas de sangue foram realizadas nos dias 7 (D-7), 14 (D-14) e 21 (D-21). As amostras de soro foram submetidas ao teste do antígeno acidificado tamponado (AAT). O coeficiente de soroconversão atribuível à vacinação foi calculado subtraindo-se da incidência de soroconversão no grupo intervenção àquela do grupo controle. No D-0, 100% (110/110) das bezerras amostradas não apresentaram reação ao teste do AAT (IC 95% [96,70% a 100%]; p < 0,05). No D-7 a soroconversão no grupo intervenção foi de 94,55% (52/55) (IC 95% [84,88% a 98,84%]; p < 0,05) e no grupo controle foi nula (0/55) (IC 95% [0,00% a 6,49%]; p < 0,05). No D-14 a soroconversão no grupo controle continuou sendo nula e a do grupo intervenção foi de 98,18% (54/55) (IC 95% [90,28% a 99,95%]; p<0,05). Assim, a soroconversão atribuível à vacinação pode variar entre 78,39% (84,88% - 6,49%) e 92,35% (98,86% - 6,49%), e entre 83,79% (90,28% - 6,49%) e 93,46% (99,95% - 6,49%) no D-7 e D-14, respectivamente. No D-21 a soroconversão nas 55 bezerras do grupo controle vacinadas no D-14 foi de 100% (55/55) (IC 95% [93,51% a 100%]; p < 0,05), mas sem diferença significativa (p>0,05) comparada à resposta no D-7 do grupo intervenção...(AU)

Evaluation of dot-blot test for serological diagnosis of bovine brucellosis

The objective of this study was to standardize and validate the dot-blot test for the serological diagnosis of bovine brucellosis, compare the results with those found in the 2-mercaptoethanol (2-ME) and complement fixation test (CF), and estimate the relative sensitivity and specificity of the dot-blot compared to these tests. Fifty bovine blood serum samples were used for the test standardization, and 1315 samples were used for evaluation and comparison between the tests; the results were compared using the Kappa indicator. At the end of standardization, it was established as optimal for the antigen obtained from Brucella abortus B19 after passing through a microorganism rupture process, the blood serum samples diluted at 1:100, and the conjugate at 1:30,000. The comparison of the dot-blot results with 2-ME showed Kappa index of 0.9939, sensitivity of 99.48%, and specificity 99.91%, with CF, Kappa index of 0.8226, sensitivity 100% and specificity 95.32%. Using the combination of the test results 2-ME and CF to establish the true condition of the animal, the dot-blot showed relative sensitivity of 100%, and relative specificity of 99.91%. The evaluated test proved to be effective and reliable, besides being easy to handle and interpret the results.(AU)

Avaliação das técnicas de imunodifusão em gel de ágar, ensaio imunoenzimático indireto e reação em cadeia da polimerase no diagnóstico da brucelose ovina / Evaluation of technical, immunodiffusion agar gel, enzyme-linked immunosorbent assay and polymerase chain reaction in the diagnosis of ovine brucellosis

A brucelose na espécie ovina tem recebido destaque, uma vez que se trata de uma enfermidade que acomete o sistema reprodutivo dos animais, provocando sério comprometimento no setor produtivo. Dessa forma, objetivou-se a avaliação de três métodos para o diagnóstico da brucelose ovina: o ensaio imunoenzimático indireto (ELISAi), a técnica imunodifusão em gel de ágar (IDGA) e a reação em cadeia da polimerase (PCR). Para tanto, utilizaram-se 211 amostras de sangue de ovinos oriundos de propriedades de nove municípios da microrregião homogênea de Teresina, Piauí. As 211 amostras de sangue foram submetidas aos testes sorológicos e à PCR, visando detectar anticorpos anti-B. ovis e DNA de Brucella ovis, respectivamente. Foram obtidos resultados positivos nos testes sorológicos, sendo 36 (17,06%) positivos no teste IDGA e sete (3,31%) positivos no teste ELISAi, contudo não houve resultados positivos na técnica de PCR. Dos métodos de diagnóstico utilizados neste estudo, o teste IDGA foi o que apresentou melhor desempenho na detecção de animais reagentes, quando comparado ao teste ELISAi e à PCR em amostras de sangue, e o percentual de animais soropositivos sugere uma ampla distribuição de ovinos infectados por Brucella ovis na região em estudo, o que pode causar prejuízos aos produtores.(AU)

Brucellosis in sheep has received a major focus, since it is a disease that affects the reproductive system of animals, causing serious impairment in the productive sector. Thus, three methods for the diagnosis of ovine brucellosis were evaluated as goal, the indirect Linked Immunosorbent Assay (ELISAi) test, the Immunodiffusion Agar Gel (AGID) technique and the Polymerase Chain Reaction (PCR). Therefore, we used 211 sheep blood samples from properties of nine municipalities of the homogeneous micro-region of Teresina, Piaui. The 211 blood samples were subjected to serologic testing and PCR to detect anti-B. ovis antibodies, and Brucella ovis DNA, respectively. Positive results in serological tests were obtained, 36 (17%) positive in the AGID test and seven (3.3%) positive to the ELISAi test, however, there were no positive results in the PCR technique. Of the diagnostic methods used in this study, the AGID test was the one that presented the best performance in the detection of reactive animals, when compared to ELISAi and PCR in blood samples and, the percentage of seropositive animals suggests a wide distribution of Brucella ovis infected sheep in the study region and could cause loss to producers.(AU)

Utilização de um teste ELISA indireto para o diagnostico da brucelose em amostras de soro de búfalas / Use of a test indirect ELISA for the diagnosis of brucellosis in buffaloes serum samples

Devido os males provocados pela Brucelose na produção de búfalos, o presente trabalho teve como objetivo comparar o desempenho dos testes de Antígeno Acidificado Tamponado (AAT) e Ensaio Imunoenzimático (ELISA) indireto, na investigação da Brucella abortus em soro de fêmeas bubalinas. Das 118 amostras de soros examinados através na técnica AAT, nenhuma amostra foi reagente a técnica. Assim, as mesmas amostras foram testadas pelo método de ELISA Indireto, onde encontrou-se 82 amostras reagentes. Dessa forma, conclui-se que a técnica do ELISA Indireto para teste de diagnóstico de triagem em bubalinos é uma boa opção por possuir excelente desempenho.

Regarding to the effects of brucellosis in buffalo production, this study were designed to compare the acidified buffered Antigen diagnostic test to indirect ELISA test performance in serum buffalo females. Samples analyzed by ATT technique did not reacted, nevertheless the same samples were submitted in indirect ELISA test and 82 were reacted positively. In accordance with this results, was concluded that the Indirect ELISA test is the best choice to the brucellosis diagnostic.