Unrecognized pediatric and adult family members of children with acute brucellosis

Abstract Background and aim Brucellosis is an infectious, contagious and zoonotic disease that occurs worldwide. The family members of an index case of brucellosis may be especially susceptible, due to sharing the same source of infection and similar risk factors for brucellosis. In this study, we propose to screen pediatric and adult family members of brucellosis index cases for detecting additional unrecognized infected family members. Materials and methods 114 family members of 41 pediatric patients with brucellosis were evaluated. All family members completed a brief questionnaire and were tested by a standard tube agglutination test (STA). Results The majority of family members (n = 96, 84.2%) were children. Among the 114 family members, 42 (36.8%) were seropositive, and 15 (35.7%) were symptomatic. The majority of the symptomatic seropositive family members (n = 12, 80%) had STA titers (≥1:640) higher than asymptomatic seropositive family members (n = 9, 33%; p = 0.004). Conclusion The routine screening of both pediatric and adult family members of index cases is a priority in endemic areas. Using this screening approach, unrecognized family members who are seropositive for brucellosis will be identified earlier and be able to receive prompt treatment.

Occurrence of anti-Brucella antibodies in intensive pig farming and in non-technified pig herds / Ocorrência de anticorpos anti-Brucella em suínos de granjas comercias e de criações de subsistência

The aim of this study was to determine the occurrence of antibodies anti-Brucella in 1,940 swine blood samples. Out of the 1,940 sera samples, 1,594 were from 30 intensive pig farming from seven different states, collected during the slaughtering of animals, and 346 samples from 56 non-technified (subsistence) pig herds from Jaboticabal region, São Paulo State, Brazil. All samples were tested by Buffered Plate Acidified Antigen (BPAA) and considered positive in case of agglutination. If positive, the samples were tested by Complement Fixation Reaction (CFR) as a confirmatory test. Out of the 1,594, two were positive for BPAA but negative for CFR, so the occurrence was 0%. Among the 346 samples, two were positive for BPAA but only one was positive in the confirmatory test, whith a titer of 1:8. Thus, the occurrence was 0.29%, an important result to demonstrate the improvement of the sanitary status of Brazilian non-technified pig herds, despite the low conditions of production.(AU)

O presente estudo foi realizado com o objetivo de se determinar a ocorrência de anticorpos anti-Brucella spp. em 1.940 amostras de sangue de suínos, das quais 1.594 amostras eram de 30 granjas comerciais, de sete diferentes Estados, coletadas durante o abate dos animais, e 346 amostras de 56 criações de subsistência da região de Jaboticabal, Estado de São Paulo, Brasil. Todas as amostras foram submetidas ao teste do Antígeno Acidificado Tamponado (AAT) e consideradas positivas caso ocorresse aglutinação. Quando positivas, as amostras eram submetidas ao teste de Reação de Fixação de Complemento (RFC) como teste confirmatório. Dentre as 1.594 amostras de suínos de granjas comerciais, duas se mostraram sensíveis ao AAT, porém, quando foram submetidas à RFC, ambas apresentaram reação negativa, levando a uma porcentagem de ocorrência de 0%. Já entre as 346 amostras de criações de subsistência, duas foram positivas ao AAT, sendo que apenas uma apresentou reação positiva no teste confirmatório, cujo título foi de 1:8. Desta forma, a ocorrência foi de 0,29%, resultado importante para demonstrar a melhoria do status sanitário dos rebanhos de subsistência brasileiros, apesar das condições precárias em que vivem.(AU)

Prevalence of Brucella spp in humans / Prevalência da Brucella spp em humanos / Prevalencia de la Brucella spp en humanos

Objective: to determine the seroprevalence of Brucella spp in humans.Method: this is an observational study, developed with 455 individuals between 18 and 64 years old, who use the Estratégia de Saúde da Família (Brazil's family health strategy). The serum samples of volunteers underwent buffered acid antigen tests, such as screening, agar gel immunodiffusion and slow seroagglutination test in tubes and 2-Mercaptoethanol.Results: among the samples, 1.98% has responded to buffered-acid antigen, 2.85% to agar gel immunodiffusion test and 1.54% to the slow seroagglutination tests on tubes/2-Mercaptoethanol. The prevalence of Brucella spp was 4.4%, represented by the last two tests.Conclusion: the results of this research suggest that the studied population is exposed to Brucella spp infection.

Objetivo: determinar a soroprevalência da Brucella spp em humanos.Método: trata-se de estudo observacional, desenvolvido com 455 indivíduos entre 18 e 64 anos, selecionados, que utilizavam a estratégia de saúde da família. As amostras de soro dos voluntários foram submetidas aos testes de antígeno acidificado tamponado, como triagem, imunodifusão em gel de ágar e aos testes de soroaglutinação lenta em tubos e 2-mercaptoetanol.Resultados: dentre as amostras, 1,98% reagiram ao antígeno acidificado tamponado, 2,85% à imunodifusão em gel ágar e 1,54% aos testes de soroaglutinação lenta em tubos/2-mercaptoetanol. Sendo a prevalência da Brucella spp de 4,4%, representada pelos dois últimos testes.Conclusão: os resultados desta pesquisa sugerem que a população estudada encontra-se exposta à infecção por Brucella spp.

Objetivo: determinar la seroprevalencia de la Brucella spp en humanos.Método: se trata de un estudio observacional, desarrollado con 455 individuos seleccionados con edades entre 18 y 64 años, que utilizaban la Estrategia de Salud de la Familia. Las muestras de suero de los voluntarios fueron sometidas a las pruebas de antígeno acidificado tamponado, como tamizaje, inmunodifusión en gel de agar y a las pruebas de seroaglutinación lenta en tubos y 2-mercaptoetanol.Resultados: entre las muestras; el 1,98% reaccionó al antígeno acidificado tamponado, el 2,85% reaccionó a la inmunodifusión en gel agar; y el 1,54%, a las pruebas de seroaglutinación lenta en tubos/2-mercaptoetanol. La prevalencia de laBrucella spp representada por las dos últimas pruebas fue del 4,4%.Conclusión: los resultados de esta investigación sugieren que la población que ha sido estudiada se encuentra expuesta a la infección por Brucellaspp.

Seguimiento clínico, serológico y mediante la reacción de polimerasa en cadena de una familia con brucelosis / Clinical, serological and polymerase chain reaction follow-up of a family with brucellosis

Introduction: Human brucellosis diagnosis is based on isolation of Brucella spp. from blood or tissue cultures with a positivity rate of 40-70% and serology techniques are used as complementary tools; recently molecular biology diagnostic techniques have been developed intending to optimize the etiological confirmation. Aim: The main objective of this work was to compare the polymerase chain reaction (PCR), against serological diagnostic tests during the clinical follow-up of a family presenting brucellosis. Methods: Seven family members who lived in the urban area of Mexico City, were monitored using the Rose Bengal test, the agglutination test as well as agglutination with 2 mecapto ethanol, blood cultures and serum PCR for a period of 27 months. The suspected source of infection was fresh goat cheese from a known endemic zone. Results: Brucella melitensis was isolated from the blood cultures of two patients. All of the patients were positive in serological and PCR tests at the beginning of this follow-up. At the end of the study, three patients responded well to the treatment and showed negative results in the serological and PCR tests. While two patients with diabetes mellitus type 2, showed positive results in the serological and PCR tests as well as persistent symptoms. Conclusion: Clinical follow-up of patients with brucellosis is of great importance, to properly evaluate the given treatment. In this sense the PCR is a great supporting tool in diagnostic testing.

Introducción: El diagnóstico de brucelosis humana es difícil pues los cultivos de sangre y tejidos tienen un rendimiento limitado (40-70%) y usualmente se recurre a la serología como recurso complementario; últimamente se han desarrollado técnicas de biología molecular que intentan optimizar la confirmación etiológica. Objetivo: Comparar la reacción de la polimerasa en cadena (RPC) con las pruebas de diagnóstico serológicas en el seguimiento clínico de una familia con brucelosis. Métodos: Siete integrantes de una familia con brucelosis que habitaban la zona urbana de Ciudad de México fueron monitoreados mediante aglutinación con antígeno Rosa de Bengala, prueba de aglutinación, aglutinación en presencia de 2 mercapto-etanol, hemocultivos y RPC en suero durante 27 meses. La probable fuente de infección de los pacientes fue el consumo de queso fresco de cabra originario de una zona endémica. Resultados: Brucella melitensis se obtuvo del hemocultivo de dos pacientes. Todos los pacientes fueron positivos a las pruebas serológicas y al RPC al inicio del seguimiento. Tres pacientes respondieron bien al tratamiento y mostraron resultados negativos en serología y RPC al final del estudio. Mientras que en dos pacientes con diabetes mellitus tipo 2 la sintomatología fue persistente, serología positiva y RPC positivos al finalizar el estudio. Conclusión: El seguimiento clínico de pacientes con brucelosis es muy importante para valorar el tratamiento, en este sentido la RPC es una herramienta que puede apoyar a otras pruebas de diagnóstico.

Desarrollo y evaluación de un protocolo serológico de fluorescencia polarizada en el estudio de anticuerpos contra Brucella spp en humanos / Development and evaluation of a serological protocol of fluorescence polarization for the preliminary study of Brucella spp antibodies in humans

A objeto de mostrar el desarrollo y alcance de un método de análisis serológico basado en la técnica de fluorescencia polarizada (FPA) a partir de una gota de sangre obtenida mediante punción capilar, se realizó la determinación de anticuerpos antibrucelosis de un conjunto de 321 personas de alto riesgo laboral. Los resultados se compararon con la data proveniente del análisis de sueros sanguíneos mediante FPA e inmunoanálisis enzimático competitivo (ELISA-c). El número de concordantes fue 318 (99,06%), los 3 discordantes (0,93%) resultaron negativos con fluorescencia polarizada en suero (FPAs) y ELISA-c, pero positivos con FPA capilar (FPAc). Los resultados comparativos de FPAc fueron: sensibilidad: 100%; especificidad: 99,05%; valor predictivo positivo: 66,67%; valor predictivo negativo: 100,0%; proporción de falsos positivos: 0,95%; proporción de falsos negativos: 0%; exactitud: 98,0%; razón de probabilidades: 203,00. La J de Youden para ambos métodos de FPA fue de 0,667. La determinación se consideró confiable y la concordancia de ambos procedimientos de FPA y ELISA-c resultó sin diferencias estadísticas (P>0,05%), lo que permite recomendar ampliamente la implementación del estudio de la brucelosis humana con sangre proveniente de punción capilar como método preliminar.

In order to show the development and scope of a serological analysis method based on fluorescence polarization assay (FPA) from a drop of blood obtained by the capillary technique, a Brucella antibody assay was performed on a group of 321 high-risk workers. The results were compared with data from the analysis of blood serum by FPA and a competitive enzyme immunoassay (ELISA-c). The number of concordance was 318 (99.06%), and discordant 3 (0.93%), which were negative in serum by fluorescence polarization (FPAs) and ELISA-c, but positive with capillary FPA (FPAc). The comparative results FPAc were: sensitivity 100%; specificity: 99.05%; positive predictive value 66.67%; negative predictive value 100.0%; false positive rate: 0.95%; false negative rate: 0%; accuracy: 98.0%; odds ratio: 203.00. The youden J for both FPA methods was 0.667. The identification was considered reliable and the correlation of both procedures, FPA and ELISA-c, was no statistically different (P> 0.05%), which allows to highly recommend the study implementation of human brucellosis with capillary blood as a preliminary method.

Seroprevalence of Brucella antibody titer in rural population of Abhar, Iran

Brucellosis is a major health problem worldwide, especially in developing countries. Following infection with brucella, antibodies appear in the serum and its titer detection can help us to evaluate the course and epidemic status of the infection. The aim of this study was to determine the seroprevalence of anti-brucella antibody titer in rural population of Abhar. In this descriptive study, 300 individuals were randomly selected for whom blood samples were screened to determine anti-brucella antibody titter, using standard tube agglutination [STA] and Coombs tests. The seroprevalence of anti-brucella antibody titer was 1.25% for STA and 4.58% for Coombs test. Totally, 14 [5.83%] individuals had titers of 1/80 or higher in STA and/or Coombs tests. Our results emphasizes on the necessity of conducting comprehensive and scheduled program of seroprevalence survey, particularly in rural area, aimed at reducing brucella prevalence as well as to guide planning and resource allocation of decision makers for future interventions

Utilidad de la determinación de anticuerpos IgG e IgM por ELISA e inmunocaptura en una serie clínica de brucelosis humana / Usefulness of the determination of IgG and IgM antibodies by ELISA and immunocapture in a clinical series of human brucellosis

Introducción: El diagnóstico de brucelosis continúa siendo complejo en la actualidad y se requieren nuevas pruebas de diagnóstico. Objetivo: Evaluar pruebas comerciales para la determinación serológica de anticuerpos anti Brucella sp mediante ELISA e inmunocaptura en una serie clínica de pacientes de la Red de Salud UC. Métodos: Estudio retrospectivo de pacientes cuyos sueros fueron recibidos en el laboratorio de Microbiología para estudio serológico de brucelosis. Se obtuvieron 2 grupos, aquellos que cumplían criterios diagnósticos de brucelosis [cuadro clínico compatible, y/o hemocultivo positivo y/o serología por seroaglutinación en tubo (SAT) en títulos > 1/160] y el grupo control. Todos los sueros se analizaron mediante aglutinación con inmunocaptura (Brucellacapt®), ELISA IgM y ELISA IgG. Resultados: De 10 pacientes con brucelosis, los resultados serológicos fueron: 8/10 positivos para ELISA IgG, 7/10 para Brucellacapt® y SAT y 5/10 para ELISA IgM. Discusión: ELISA IgG por si solo fue la mejor prueba para el diagnóstico de brucelosis. La combinación ELISA IgG+ Brucellacapt® alcanza un buen rendimiento de detección (9/10) y puede ser una alternativa a la SAT.

Introduction: The diagnostic difficulties of brucellosis makes the evaluation of new diagnostic tests necessary. Objectives: Evaluation of different commercial tests in the serological diagnosis of brucellosis by ELISA and immunocapture antibodies in a clinical series of patients with brucellosis of the Health Network of the Catholic University of Chile. Methods: All the serums received in the Laboratory of Microbiology for suspicion of brucellosis during five years were studied. Two groups were obtained, one that fulfilled diagnostic criteria for brucellosis [clinical evidence, and/or positive blood culture and/or seroagglutination test (SAT) in titers > 1/160] and the control group. Each serum sample was analyzed using irnmunocapture-agglutination test (Brucellacapt®), ELISA IgM and IgG. Results: Of 10 patients with brucellosis, the serologic results were: 8/10 positives for ELISA IgG, 7/10 for Brucellacapt® and SAT, and 5/10 for ELISA IgM. Discussion: ELISA IgG alone was superior than SAT. The combination ELISA IgG/ Brucellacapt® reaches the best detection performance (9/10) and can be an alternative to SAT.

Prevalencia de anticuerpos séricos contra la bacteria Brucella sp. en una población humana tropical

Prevalence of serum antibodies for the bacterium Brucella sp. in a tropical human population. Brucellosis is a systemic bacterial disease that can last years if not treated properly. The laboratory diagnosis is made by serological tests or isolation of the agent. We studied the prevalence of antibodies against Brucella sp. in inhabitants of rural communities of Cartago, Costa Rica, who are dedicated mainly to dairy cattle activities. We analyzed 714 representative samples with the Rose Bengal plate agglutination test (RBT) and the standard agglutination test in microplate (SAT). The overall prevalence was 0.87 %. No seroconversion was demonstrated for seropositive individuals. Even though 71 % of the population mentioned consuming non-pasteurized milk, no statistically significant association was found (1.09 %, IC 0.30-2.77) between milk consumption and the presence of antibodies suggestive of infection by Brucella sp. As a brucellosis high-risk population, the absence of symptoms in the population agrees with the observed titers of antibodies, suggesting a low previous exposure to the agent. Rev. Biol. Trop. 55 (2): 385-391. Epub 2007 June, 29.

La brucelosis es una enfermedad bacteriana generalizada con tendencia a la cronicidad si no se trata adecuadamente. El diagnóstico de laboratorio se realiza por el aislamiento e identificación del agente o en la mayoría de los casos mediante pruebas serológicas. En este estudio se informa la prevalencia de anticuerpos séricos contra Brucella sp. en habitantes de comunidades rurales de Cartago dedicadas principalmente a la ganadería de leche. Se analizó un total de 714 muestras representativas de la población mediante la técnica de aglutinación Rosa de Bengala en lámina (RBT) y la prueba de aglutinación en microplaca (SAT). Se encontró una prevalencia de 0.87 %, y en ninguna persona seropositiva se demostró seroconversión. Aún, cuando el 71 % de la población refirió consumir leche no pasteurizada, no se encontró asociación estadísticamente significativa (1.09 %, IC 0.30-2.77) entre el consumo de leche no pasteurizada y la presencia de anticuerpos sugestivos de infección por Brucella sp. A pesar de ser una zona de alta prevalencia de brucelosis bovina por Brucella abortus, la ausencia de síntomas en la población y los bajos títulos de anticuerpos observados sugieren una escasa exposición previa al agente.

Brucella epididymo-orchitis: a consideration in endemic area

Brucellosis is a zoonotic disease caused by Brucella sp. and may affect many parts of the body. Brucella epididymo-orchitis had been reported in up to 20 percent of patients with brucellosis. This is a case report of Brucella epididymo-orchitis in a Saudi male patient. He presented with a unilateral swelling of the left testicle. He had fever, arthralgia and night sweats. Ultrasound examination revealed enlarged left epididymis and testicle. Brucella serology was positive and the patient responded to treatment with doxycycline and gentamicin. Thus, brucella infection should be considered in the differential diagnosis of patients presenting with epididymo-orchitis from an endemic area.

Rapid enzyme-linked immunosorbent assay for the diagnosis of human brucellosis in surveillance and clinical settings in Egypt

To optimize and standardize an enzyme-linked immunosorbent assay [ELISA] for rapid diagnosis of human brucellosis in clinical cases identified during a surveillance study for acute febrile illness [AFI]. Serum samples from patients presenting with AFI at 13 fever hospitals across Egypt between 1999 and 2003 were kept frozen at NAMRU-3 and used in this study. The assay was evaluated in 5 subject groups: brucellosis cases confirmed by blood culture [group I, n=202] 87% positive by standard tube agglutination test [TA], brucellosis cases exclusively confirmed by TA [group II, n=218], blood cultures from AFI cases positive for bacterial species other than Brucella [group III, n=103], AFI cases with unexplained etiologies [group IV, n=654], and healthy volunteers [group V, n=50]. All members of groups III-V were negative for brucellosis by TA. Sensitivity and specificity of ELISA for total specific antibodies were >=96% versus 87% for TA as compared to microbial culture, the current gold standard method for Brucella identification. Assessment of Brucella antibody classes by ELISA in random subsets of the 5 groups showed significantly high [p>0.001] levels of anti Brucella IgG [>=81%] and IgM [>=90%] in groups I and II only. The obtained sensitivity and specificity results indicate that our ELISA is more suitable for AFI surveillance and clinical settings than blood culture and TA. The developed assay is also cost-effective, easier to use, faster, and the coated plates can be stocked for at least 8 months, providing a potential for field use and automation

Seroprevalence of human brucellosis in a rural area of Western Anatolia, Turkey.

This study was conducted to determine the seroprevalence of human brucellosis and identify the potential risk factors in a rural area of Western Anatolia, Turkey. A simple random-sampling method was used for identifying 1,052 subjects for the study. Blood samples, collected from all the subjects, were studied following the methods of Rose Bengal slide agglutination and standard tube agglutination tests. One thousand and one samples (95.2%) were seronegative, and 51 (4.8%) were seropositive. There was a statistically significant correlation between seropositivity and age, sex, consuming fresh cheese and cream made from unboiled milk (p values 0.005, 0.019, <0.001, and <0.001 respectively). Seropositivity was not related to educational level (0.270). It is concluded that pasteurization of milk and dairy products and education regarding eating habits must be pursued for eradication of human brucellosis from rural areas. The findings of the study suggest that human brucellosis is still an important public-health problem in the western Anatolia region of Turkey, especially in rural areas.

Prevalence of Brucella antibodies in sera of cows in Bangladesh

The study was carried out to investigate the prevalence of Brucella antibodies in sera of 120 cows in Bangladesh Agricultural University Dairy Farm and adjacent villages, Bangladesh. The epidemiological history and blood was collected from the cows. The serum samples were subjected to Rose Bengal Test (RBT)and plate agglutination test (PAT) for initial screening of Brucella antibodies and the positive sera samples were then subjected to tube agglutination test (TAT)for further confirmation. The higher rate of Brucella antibody was recorded in rural farm (5.0%)than organized farm (2.5%)and in pregnant cows (5.9%)than non-pregnant cows (4.7%). A total of 3 (4%)Brucella positive antibody cases were recorded in cows of above four years of age whereas, 1 (2.3%)positive case was found in cows of less than 4 years of age. The study revealed that number of Red Shindi was the highest and the prevalence of brucellosis in Bangladesh cow population is not negligible and it is worthwhile to consider adoption of preventive measures.

Seroprevalencia de anticuerpos anti-Brucella en disponentes de sangre con fines terapéuticos en tres bancos de sangre del Instituto Mexicano del Seguro Social / Anti-Brucella Antibody Seroprevalence in Blood Donors for Therapeutic Ends at Three Blood Banks of the Mexican Institute of Social Security

Introducción: la brucelosis es una zoonosis, que causa grandes pérdidas económicas en las zonas conurbanas de la Ciudad de México y es un problema importante de salud pública en los habitantes circunvecinos al Distrito Federal. El objetivo fue detectar anticuerpos anti-Brucella y según los resultados que proporcionó esta investigación, se propone como prueba de laboratorio de escrutinio en los donadores de sangre. Material y métodos: se analizaron 500 sueros sanguíneos de disponentes efectivos seleccionados y cuya muestra fue representativa de acuerdo al análisis estadístico elaborado. Las pruebas de laboratorio incluyeron Rosa de Bengala, Aglutinación Estándar en Microplaca y 2 Mercaptoetanol. Resultados: de los 500 sueros analizados 18 mostraron seropositividad con una tasa de seroprevalencia de 3.6%, predominando el sexo masculino (83.4%), por grupo de actividad las secundarias (72.2%), por grado de estudios académicos los de secundaria fueron los de mayor positividad (55.6%). Conclusión: la brucelosis posee características epidemiológicas peculiares en los bancos de sangre participantes en esta investigación, por lo que es importante incluir pruebas de escrutinio en búsqueda de anticuerpos anti-Brucella en los disponentes de sangre efectivos.

Introduction: to determine seroprevalence for Brucella sp. in blood donors, a serologic study was carried out at three blood banks of the Instituto Mexicano del Seguro Social (IMSS). Methods: 500 blood samples were taken from selected blood donors. Laboratory tests were used, such as Bengal rose (BR), Standard agglutination in microplate (SAM) and in presence of 2-Mercaptoethanol agglutination in microplate (2ME), which were applied to 500 blood sera from selected effective blood donors. The sample was representative according to the statistical analysis developed. Results: 18 of 500 analyzed sera were positive, with seroprevalence of 3.6%, male sex (83.4%), predominating, as secondary activity group (72.2%). According to academic archivement, blood donors with secondary school had highest seropositivity (55.6%). Conclusion: In this study, we conclude that brucellosis has peculiar epidemiologic characteristics in blood banks that participated in this research; therefore it is highly recommended to perform screening tests such as BR, SAM, and 2ME to identified anti-Brucella antibodies in the sera of effective blood donors.

Seroprevalence of Brucella in an elderly population in mid-Anatolia, Turkey.

Brucellosis is a widespread infectious disease in the mid-Anatolia regions of Turkey. This study investigated the prevalence of Brucella infection in elderly people of this region. In total, 750 elderly subjects were chosen by a simple random-sampling method. Blood samples were evaluated by the Brucella Wright agglutination test. Brucella seropositivity was detected in 24 (3.2%) of the 750 subjects. Although there was no statistical correlation between Brucella seropositivity and sex or educational level (p > 0.05), seropositivity was statistically significant with subjects exposed to risk factors (p < 0.001). It is concluded that Brucella infection is still an important public-health problem in the cities of mid-Anatolia.

Evaluation of A newly developed DOT-ELISA kit for the diagnosis of human brucellosis.

A new dot-ELISA kit for detection of Brucella antibodies in human sera was developed and compared with that of serum agglutination test, Rose Bengal plate test, rapid slide agglutination and Coomb's antiglobulin test. Following testing of 120 human sera from suspected patients of occupational risk, 25 gave positive reaction in Rose Bengal plate test, 25 in rapid slide agglutination test, 26 in serum agglutination test, 27 in Coomb's antiglobulin test and 28 in dot-ELISA kit. Dot-ELISA kit picked up more positive than any other Serological test, indicating its superiority over the other laboratory tests for the diagnosis of brucellosis.

Selected epidemiological features of human brucellosis in Yazd, Islamic Republic of Iran: 1993-1998

Brucellosis is a significant health problem in countries where control of zoonoses is inadequate. During 1993-98, we analysed sera and cultures from 792 suspected brucellosis patients who presented with histories of fever, chills, night sweating, weakness, malaise and headache to the referral hospital in Yazd. Cases were investigated by tube agglutination test [TAT] and 2-mercaptoethanol test [2-MET] and a questionnaire was completed for each.TAT titre was > / = 1:1 60 for 745 patients [94.1%] and 2-MET was positive for 42 [5.3%]. Of 745 confirmed cases, 460 were from 1996-1997. Prevalence was highest in summer [39.5%] and more common males than among females. Prevalence was highest among those aged 10-19 years [27.7%]. Most patients had a history of infected cheese, milk and milk product consumption [98%]

Production and characterization of monoclonal antibodies against brucella S [99] surface antigens

By immunizing mice with killed whole bacterial cells of Brucella abortus S [99], a panel of six hybridomas producing monoclonal antibodies [mAb] specific for the surface antigens of this bacterium were produced. ELISA was used to screen the hybridoma supernatants. Immunoblots of the cell extract indicated that three mAb were specific for S-LPS [Ba-1, Ba-2, Ba-3] and three others were reactive with major outer membrane proteins [OMP] [Ba-4, Ba-5, Ba-6]. The OMP recognized by these antibodies were the proteins with molecular masses of 25-27 kDa [Ba-4, Ba-5] and 36-38 kDa [Ba-6]. None of the four mAb including Ba-3, Ba-4, Ba-5 and Ba-6 cross reacted with any other bacteria close to Brucella abortus, but Ba-1 and Ba-2 cross reacted with B. melitensis 16M and B. suis. By using cell extract and killed whole cell Ag in ELISA, it was indicated that all mAb except Ba-6 have better reactivity with cell extract Ag, but Ba-6 mAb reacted with killed whole cell Ag better than cell extract Ag