Brucella spp. en el hato ovino costarricense

Modalidad: TesisLa brucelosis en ovinos es causada por Brucella melitensis, B. abortus, y B. ovis, provocando principalmente en el caso de las dos primeras especies, problemas en la reproducción de las hembras y en el caso de B. ovis, epididimitis contagiosa del carnero. Ante el auge de la producción ovina en Costa Rica, el presente estudio da a conocer el estado actual de la brucelosis en estos animales en el país. Para este fin, se obtuvieron sueros de 510 animales pertenecientes a diez fincas distribuidas en ocho regiones a nivel nacional. A estas muestras se les realizó la prueba de Rosa de Bengala (RB) por dos métodos, el de rutina utilizado para bovinos y la modificación sugerida por la OIE para ovinos. También, estas muestras fueron analizadas utilizando ELISA indirecto (ELISAi), ELISA competitivo (ELISAc) y la prueba de fluorescencia polarizada (FPA). Para la validación y evaluación del rendimiento de todas las pruebas se utilizó 20 sueros de ovinos con aislamiento de B. melitensis y 20 sueros libres de brucelosis. Además, tres de los animales que resultaron positivos en RB y en ambos ELISAs, fueron sacrificados, obteniéndose aislamientos morfológicamente y bioquímicamente compatibles con Brucella spp., sin embargo, la caracterización molecular, la inmunohistoquímica y la inmunofluorescencia directa realizada en estos aislamientos revelaron que no pertenecían al género Brucella. En términos generales, la seroprevalencia contra antígenos de Brucella en ovinos a nivel nacional obtenida es baja, ya que correspondió de 0.2 % al 0.98 % en la población analizada, y por lo tanto, se deben seguir apoyando a los productores nacionales y establecer reglamentaciones para proteger al hato ovino nacional y limitar el ingreso de animales vivos solamente de países con prevalencias igual o menores a las descritas para Costa Rica.Brucellosis in sheep is caused by Brucella melitensis, B. abortus, and B. ovis, causing mainly in the case of the first two species, problems in reproducing females and in the case of B. ovis, contagious epididymitis in rams. With the growth of sheep production in Costa Rica, this study discloses the current status of brucellosis in these animals in the country. For this purpose, sera from 510 animals were obtained, belonging to ten farms in eight regions nationwide. These samples underwent testing of Rose Bengal (RB) by two methods, including routine that is used for cattle and the modification suggested by the OIE for sheep. Also, these samples were analyzed using indirect ELISA (ELISAi), competitive ELISA (ELISAc) and fluorescence polarization assay (FPA). Sera from 20 sheep with isolation of B. melitensis and 20 sera free of brucellosis were used for validation and performance evaluation of all tests. In addition, three animals that were positive in both ELISA and RB were sacrificed. Isolations compatibles morphologically and biochemically with Brucella spp. were obtained, however, molecular characterization, immunohistochemistry and direct immunofluorescence demonstrated that these isolates did not belonged to the Brucella genus. Overall, the seroprevalence against Brucella antigens in sheep at national level obtained is low, as it accounted for 0.2 % to 0.98 % in the population tested, and therefore, should continue to support national producers and establish regulations to protect the national sheep herd and limit the entry of live animals only from countries with prevalence equal to or less than those described for Costa Rica.Escuela de Medicina Veterinari

Seroprevalence of Toxoplasma gondii and Neospora caninum infections and associated factors in sheep from Costa Rica

The presence of antibodies against Toxoplasma gondii and Neospora caninum were analyzed in 392 sheep sera from ten Costa Rican ovine flocks using indirect immuno-enzymatic assays. Additionally, general information about sheep management, environment, and clinical reproductive disorders was assessed through a questionnaire to inquire factors related to these apicomplexan parasites. A total of 161 (41.1%) serum samples reacted positive to T. gondii, 43 (10.9%) to N. caninum and 26 (6.63%) to both parasites. Toxoplasma gondii serorreactors were detected in all the analyzed flocks (100.0%), meanwhile N. caninum antibodies were found in nine flocks (90%), from the six Costa Rican regions. Factors associated with T. gondii were the co-presence of cattle (OR = 5.06; C.I.95%; 2.08–12.30; p: <0.001), grey foxes (Urocyon cinereoargenteus) and opossums (Didelphis marsupialis) (OR = 2.44; C.I.95%; 1.50–3.95; p: <0.001) inside or around the farms, and the presence of peccaries (Tayassu sp.) (OR = 0.35; C.I.95%; 0.16–0.74; p: 0.0058) was a variable associated with N. caninum seropositivity. The obtained results of T. gondii and N. caninum infections in sheep flocks from Costa Rica should be considered for the proper prevention and control strategies against these apicomplexan abortive parasites. Keywords: Abortion, Sheep, Toxoplasmosis, Neosporosis, Costa Ric

Brucellosis in mammals of Costa Rica: An epidemiological survey.

Brucellosis has been an endemic disease of cattle and humans in Costa Rica since the beginning of XX century. However, brucellosis in sheep, goats, pigs, water buffaloes, horses and cetaceans, has not been reported in the country. We have performed a brucellosis survey in these host mammal species, from 1999-2016. In addition, we have documented the number of human brucellosis reported cases, from 2003-2016. The brucellosis seroprevalence in goat and sheep herds was 0.98% and 0.7% respectively, with no Brucella isolation. Antibodies against Brucella were not detected in feral or domestic pigs. Likewise, brucellosis seroprevalence in horse and water buffalo farms was estimated in 6.5% and 21.7%, respectively, with no Brucella isolation. Six cetacean species showed positive reactions against Brucella antigens, and B. ceti was isolated in 70% (n = 29) of striped dolphins (Stenella coeruleoalba). A steady increase in the diagnosis of human brucellosis cases was observed. Taking into account the prevalence of brucellosis in the various host mammals of Costa Rica, different measures are recommended

Virulent Brucella nosferati infecting Desmodus rotundus has emerging potential due to the broad foraging range of its bat host for humans and wild and domestic animals

Desmodus rotundus, vampire bats, transmit dangerous infections, and brucellosis is a hazardous zoonotic disease, two adversities that coexist in the subtropical and tropical areas of the American continent. Here, we report a 47.89% Brucella infection prevalence in a colony of vampire bats inhabiting the tropical rainforest of Costa Rica. The bacterium induced placentitis and fetal death in bats. Wide-range phenotypic and genotypic characterization placed the Brucella organisms as a new pathogenic species named Brucella nosferati sp. nov., isolated from bat tissues, including the salivary glands, suggesting feeding behavior might favor transmission to their prey. Overall analyses placed B. nosferati as the etiological agent of a reported canine brucellosis case, demonstrating its potential for infecting other hosts. To assess the putative prey hosts, we analyzed the intestinal contents of 14 infected and 23 non-infected bats by proteomics. A total of 54,508 peptides sorted into 7,203 unique peptides corresponding to 1,521 proteins were identified. Twenty-three wildlife and domestic taxa, including humans, were foraged by B. nosferati-infected D. rotundus, suggesting contact of this bacterium with a broad range of hosts. Our approach is appropriate for detecting, in a single study, the prey preferences of vampire bats in a diverse area, demonstrating its suitability for control strategies where vampire bats thrive.Desmodus rotundus, los murciélagos vampiro, transmiten infecciones peligrosas, y la brucelosis es una peligrosa enfermedad zoonótica, dos adversidades que coexisten en las zonas subtropicales y tropicales del continente americano. Aquí se informa de una prevalencia de infección por Brucella del 47,89% en una colonia de murciélagos vampiro que habitan la selva tropical de Costa Rica. La bacteria indujo placentitis y muerte fetal en los murciélagos. Una amplia caracterización fenotípica y genotípica situó a los organismos de Brucella como una nueva especie patógena denominada Brucella nosferati sp. nov., aislada de tejidos de murciélagos, incluidas las glándulas salivales, lo que sugiere que el comportamiento alimentario podría favorecer la transmisión a sus presas. Los análisis globales situaron a B. nosferati como agente etiológico de un caso de brucelosis canina notificado, lo que demuestra su potencial para infectar a otros hospedadores. Para evaluar los posibles huéspedes presa, analizamos mediante proteómica el contenido intestinal de 14 murciélagos infectados y 23 no infectados. Se identificó un total de 54.508 péptidos clasificados en 7.203 péptidos únicos correspondientes a 1.521 proteínas. D. rotundus infectado con B. nosferati se alimentó de veintitrés taxones de fauna silvestre y doméstica, incluidos los humanos, lo que sugiere el contacto de esta bacteria con una amplia gama de hospedadores. Nuestro enfoque es apropiado para detectar, en un solo estudio, las preferencias de presa de los murciélagos vampiro en una zona diversa, lo que demuestra su idoneidad para las estrategias de control donde prosperan los murciélagos vampiro. IMPORTANCIA: El descubrimiento de que una elevada proporción de murciélagos vampiro en una zona tropical está infectada con Brucella nosferati patógena y que los murciélagos se alimentan de seres humanos y muchos animales salvajes y domésticos es relevante desde la perspectiva de la prevención de enfermedades emergentes. En efecto, los murciélagos que albergan B. nosferati en sus glándulas salivales pueden transmitir esta bacteria patógena a otros huéspedes. Este potencial no es trivial ya que, además de la patogenicidad demostrada, esta bacteria posee todo el arsenal virulento necesario de los organismos Brucella peligrosos, incluidos los que son zoonóticos para el ser humano. Nuestro trabajo ha sentado las bases para futuras acciones de vigilancia en los programas de control de la brucelosis en los que prosperan estos murciélagos infectados. Además, nuestra estrategia para identificar el área de alimentación de los murciélagos puede adaptarse para explorar los hábitos alimentarios de diversos animales, incluidos los artrópodos vectores de enfermedades infecciosas, y por tanto ser de interés para un público más amplio, además de los expertos en Brucella y murciélagos.Universidad Nacional, Costa RicaEscuela de Medicina Veterinari

Numbers of ovine and caprine herds and numbers of animals by geographical region in Costa Rica (2015).

<p>Numbers of ovine and caprine herds and numbers of animals by geographical region in Costa Rica (2015).</p

Sampling of animal stocks, in the six regions of CR.

<p>The epidemiological regions are as follow: 1, Northern Huetar; 2, Central; 3, Brunca; 4, Chorotega; 5, Caribbean Huetar; 6, Central Pacific. Each red dot represents an animal stock facility.</p