Occurrence of hydatidosis and cysticercosis in cattle in southern Rio Grande do Sul, Brazil, from 2013 to 2016 / Ocorrência de hidatidose e cisticercose em bovinos na região sul do Rio Grande do Sul, de 2013 a 2016

Hydatidosis and cysticercosis are parasitoses caused by the larval forms of the cestodes Equinococcus spp. and Taenia spp., which belong to the Taeniidae family. Their definitive hosts are canids and humans, respectively, with ruminants as the intermediate hosts and humans as an accidental host of both diseases. These parasites are responsible for large economic losses in slaughterhouses due to condemnation of carcasses and by-products. The present study reports the mean incidence rates of hydatidosis and cysticercosis in cattle slaughtered in the southern region of Rio Grande do Sul state, Brazil. The incidence rates observed between 2013 and 2016 were 19.96% and 0.9%, respectively, with decreased tendency of occurrence of both diseases in those years. Despite the downward tendency of the diseases, hydatidosis presented high incidence. Hydatidosis performance over the years was characterized by significant increase in the number of cases, followed by marked decrease. Cysticercosis presented a decrease in number of cases at the beginning and the end of each year. These diseases have a significant socioeconomic impact as they are responsible for large losses in the livestock industry, due to reduced productivity and carcass condemnation, and represent a risk to public health.(AU)

Hidatidose e cisticercose são parasitoses causadas pelas formas larvais dos cestódeos Equinococcus spp. e Taenia spp., pertencentes a família Taeniidae, possuem como hospedeiros definitivos canídeos e o homem respectivamente, sendo os ruminantes os hospedeiros intermediários, e o homem um hospedeiro acidental, em ambas as doenças. Estas parasitoses são responsáveis por grandes perdas econômicas em frigoríficos, devido a condenações de carcaças e subprodutos. O presente artigo relata que a incidência média de hidatidose e cisticercose em bovinos abatidos na região sul do Rio Grande do Sul, entre os anos de 2013 e 2016, foi de 19,96% e 0,9% respectivamente, sendo avaliada uma tendência de queda no número de casos de ambas as doenças ao longo dos anos analisados. Apesar da tendência de queda das doenças, a hidatidose apresentou uma alta incidência. O comportamento da hidatidose ao longo dos anos foi caracterizado por aumentos significativos no número de casos da doença, seguidos por acentuadas quedas. Já a cisticercose apresentou uma diminuição no número de casos no início e no final de cada ano. Estas doenças apresentam grande impacto socioeconômico, pois são responsáveis por grandes perdas na pecuária, por redução na produtividade e condenações, além de representarem um risco à saúde pública.(AU)

Echinococcosis and other parasitic infections in domestic dogs from urban areas of an argentinean Patagonian city

In urban populations of South America, dogs with free access to public areas represent a public health concern. The primary consequence of roaming dogs on human health is the transmission of infectious and parasitic diseases mainly through feces contamination. The main diseases likely to be transmitted are hydatidosis or echinococcosis, larva migrans, and giardiasis. In Argentina, hydatidosis ranks among the most prevalent zoonosis. Although it is considered a rural disease, the circulation of this parasite in urban areas has been documented. The aim of this work was to survey intestinal parasites in canine feces from two low-income urban neighborhoods of Bariloche city, Argentina, and to assess their seasonal variation. During 2016, 188 fresh dog feces were collected from sidewalks in 40 randomly selected blocks from the neighborhoods. Each sample was processed by Sheater flotation and tested for a coproantigen (CAg) by ELISA. The percentage of parasitized feces was 65.3% (95% CI: 55.9%-73.8%). Eleven parasite species were found, 3 protozoan, 3 cestodes, and 5 nematodes. Echinococcus sp. was present in 9.3% of the samples (95% CI: 4.7%-16.1%). Canine echinococcosis rates resulted similar to rates found previously in other neighborhoods of the city. The life cycle of Echinococcus sp. is sustained in urban areas by the entry of parasitized livestock, domiciliary slaughtering, and inadequate deposition of offal. The risk of Echinococcus sp. transmission to people in these neighborhoods is very high, due to high density of free-roaming dogs and high percentages of infected feces, similar to percentages observed in rural areas.

En las poblaciones urbanas de América del Sur, los perros con acceso libre a áreas públicas representan un problema de salud pública. La principal consecuencia es la transmisión de enfermedades infecciosas y parasitarias a través de la contaminación por heces. Las principales enfermedades que pueden transmitirse son hidatidosis, larva migrans y giardiasis. En Argentina, la hidatidosis es una de las zoonosis más prevalentes y aunque es considerada una enfermedad rural, algunos estudios muestran la circulación de este parásito en zonas urbanas. El objetivo fue registrar los parásitos intestinales en heces caninas de dos barrios de bajos ingresos de la ciudad de Bariloche, Argentina, y evaluar su variación estacional. Durante 2016, se recolectaron 188 heces frescas de perros en 40 manzanas seleccionados aleatoriamente. Las heces se procesaron mediante flotación de Sheater y una prueba ELISA de coproantigeno (CAg). El porcentaje de heces parasitadas fue del 65.3% (IC 95%: 55.9%-73.8%). Se encontraron 11 especies de parásitos, 3 protozoos, 3 cestodes y 5 nematodes. Echinococcus sp. estuvo presente en el 9.3% de las heces (IC 95%: 4.7% -16.1%). La equinococosis canina mostró valores similares a estudios previos en otros barrios de la ciudad. El ciclo de vida Echinococcus sp. se mantiene en las zonas urbanas por entrada de ganado parasitado, faena domiciliaria y deposición inadecuada de vísceras. El riesgo de transmisión de Echinococcus sp. en estos barrios es alto, debido a la alta densidad de perros sueltos y al alto porcentaje de heces infectadas, similar al de las zonas rurales.

Hiperendemia de equinococosis y fertilidad quística en porcinos del valle interandino de Huancarama, Perú / Echinococcosis hyper-endemic and cystic fertility in pigs of the inter-andean valley of Huancarama, Peru

El objetivo de la investigación fue determinar el porcentaje de infección de equinococosis en porcinos, fertilidad quística y factores asociados. Estudio de corte transversal. La población estuvo conformada por 579 porcinos faenados en el matadero de Huancarama. Los quistes hidatídicos fueron detectados mediante evaluación post mórtem. La fertilidad se determinó midiendo el diámetro de los quistes y observando microscópicamente la membrana germinativa en busca de protoescólices. El porcentaje de infección de equinococosis quística fue de 76,7% (IC95%: 73,2-80,3). Los porcinos mayores a dos años tuvieron más oportunidad de presentar quistes (RP 1,03; IC95%:1,0-1,1; p<0,01), al igual que los provenientes del distrito de Andahuaylas (RP 1,2; IC95%: 1,1-1,4; p<0,01). Los quistes pulmonares presentaron menor porcentaje de infección que los hepáticos. Se examinaron 346 quistes hidatídicos de 334 porcinos, se encontró una fertilidad total de 42,8% (IC95%: 37,4-48,1).

The objective of the research was to determine the percentage of echinococcosis infection in swine, cystic fertility and associated factors. Cross-sectional study. The population was formed by 579 pigs slaughtered in the slaughterhouse of Huancarama. Hydatid cysts were detected by postmortem evaluation. Fertility was determined by measuring the diameter of the cysts and microscopically observing the germinative membrane in search of protoscoleces. The percentage of cystic echinococcosis infection was 76.7% (CI 95%: 73.2-80.3). Pigs older than two years were more likely to have cysts (RP 1.03; CI 95%: 1.0-1.1; (P < 0.01), as well as those coming from the Andahuaylas district (RP 1.2; CI 95%: 1.1-1.4; P < 0.01). Lung cysts showed a lower percentage of infection than hepatic ones. We examined 346 hydatid cysts of 334 pigs, a total fertility of 42.8% was found (CI 95%: 37.4-48.1).

Molecular epidemiology of cystic echinococcosis: genotypic characterization in humans and different livestock / Epidemiología molecular de la equinococosis quística: caracterización genotípica en humanos y diferentes animales

Echinococcus Granulosus (EG) is the major cause of cystic echinococcosis in humans and livestock in the world. In Chile is a zoonosis of great importance. The most frequently affected geographic areas are the Regions of Aysén, Los Rios, Los Lagos, Coquimbo and the Araucanía. Hence, it was discovered that in endemic areas of hydatidosis there could be several strains and genotypes of EG. In addition, there is evidence that some strains and genotypes are more infectious for human beings than others. This interesting phenomenon of the biology of EG has been studied using molecular biology techniques based on polymerase chain reaction (PCR) and DNA sequence analysis, which has made it possible to characterize the cestode species complex called EG sensu lato (s l) as being comprised of EG sensu stricto (s.s.) (Genotypes G1-G3), E. equinus (G4), E. ortleppi (G5) and E. canadensis (G6-G10), which present an important phenotypic variation detectable in characteristics of the biological cycle, specificity of the intermediate host, pattern of development, pathogenicity, antigenicity, transmission dynamics and, consequently, in the measures needed to control the disease. The aim of this manuscript is to describe the different genotypes of EG described in humans and different livestock host reported in the literature.

Echinococcus granulosus (EG) es la principal causa de equinococosis quística en humanos y ganado en el mundo. En Chile hay una zoonosis de gran importancia. Las zonas geográficas más afectadas son las Regiones de Aysén, Los Ríos, Los Lagos, Coquimbo y la Araucanía. Por lo tanto, se descubrió que en áreas endémicas de hidatidosis podría haber varias cepas y genotipos de EG. Además, hay pruebas de que algunas cepas y genotipos son más infecciosos para los seres humanos que otros. Este interesante fenómeno de la biología del EG ha sido estudiado utilizando técnicas de biología molecular basadas en la reacción en cadena de la polimerasa (PCR) y análisis de secuencias de ADN, lo que ha permitido caracterizar el complejo de cestode llamado EG sensu lato (sl) EG (G3) y E. canadensis (G6-G10), que presentan una importante variación fenotípica detectable en las características del ciclo biológico, especificidad del huésped intermedio, patrón de desarrollo, patogenicidad, antigenicidad, dinámica de transmisión y, por consiguiente, en las medidas necesarias para el control de la enfermedad. El objetivo de este manuscrito fue describir los diferentes genotipos de EG descritos en humanos y diferentes animales de ganado reportados en la literatura.

Post-immunization immunohistochemical expression of Caspase 3 and p53 apoptotic markers in experimental hydatidosis / Expressão imuno-histoquímica de marcadores de apoptose Caspase 3 e p53 pós-imunização em hidatidose experimental

Abstract The aim of this study was to investigate post-immunization apoptotic changes in experimental hydatidosis, using Caspase 3 and p53 immunohistochemical markers. Two groups of rabbits were immunized with a crude antigen (group 1) or a partially purified antigen (group 2) and were compared to an infected non-immunized control group. More effective immune responses were obtained in group 2 than group 1, signified by fewer and smaller cystic lesions and more severe destructive changes. Normal growth of cysts was attained in the control group, with no expression of apoptotic markers. Significantly higher expression of Caspase 3 and p53 were observed in group 1 compared to group 2, as indicated by OD and area percentage, respectively (Group 1 Caspase 3: 0.89±0.21, 93.5%±6.2; Group 1 p53: 0.46±0.18, 53.26%±11.6; Group 2 Caspase 3: 0.52±0.15, 49.23%±11.7; Group 2 p53: 0.19±0.4, 18.17%±7.3). Vaccine-induced immune responses and cellular damage may underlie the expression of apoptotic markers that appeared to result in a degenerative and atrophic course of action upon immunization. The results of the current study emphasize the importance of immunization for the stimulation of protective immune responses and in preventing mechanisms of evasion to ensure normal cell growth. A cost/benefit control program that implements proper vaccine preparations should be further assessed for complete elimination of severe infections in endemic areas.

Resumo O objetivo do presente estudo foi investigar mudanças de apoptose pós-imunização em hidatidose experimental, usando os marcadores imuno-histoquímicos Caspase 3 e p53. Dois grupos de coelhos foram imunizados com antígeno bruto (grupo 1) e com antígeno parcialmente purificado (grupo 2). Estes grupos foram comparados a um grupo controle infectado e não-imunizado. Respostas imunes mais eficientes foram obtidas do grupo 2, que apresentou lesões císticas menores e menos frequentes, e mudanças destrutivas mais graves. Cistos cresceram normalmente no grupo controle, sem expressão dos marcadores de apoptose. Expressões significativamente mais altas de Caspase 3 e p53 foram observadas no grupo 1 quando comparado ao grupo 2, como indicado por DO e área de percentagem, respectivamente (Grupo 1 Caspase 3: 0,89±0,21, 93,5%±6,2; Grupo 1 p53: 0,46±0,18, 53,26%±11,6; Grupo 2 Caspase 3: 0,52±0,15, 49,23%±11,7; Grupo 2 p53: 0,19±0,4, 18,17%±7,3). Respostas imunológicas induzidas por vacinas e danos celulares podem ser a base para a expressão dos marcadores de apoptose cujos desfechos demonstraram ação degenerativa e atrófica durante imunização. Os resultados do presente estudo enfatizam a importância da imunização para o estímulo de respostas imunes de proteção e para mecanismos de prevenção de evasão para garantir crescimento celular normal. Um programa de controle de custo/benefício que implemente preparações de vacinas adequadas deve ser analisado em mais detalhe para a completa eliminação de infecções graves em áreas endêmicas.

Caracterización epidemiológica de hidatidosis humana y animal en la Región de Los Ríos, 1999-2009 / Epidemiological description of human and animal hydatidosis in Los Ríos region, 1999- 2009

Objective: To determine the prevalence of hydatidosis in humans and livestock in the Los Ríos region during the years 1999-2009. Methods: A retrospective survey of all discharge records of patients undergoing removal of cysts produced by Echinococcus granulosus during the period 1999-2009 in the Hospital Clinico Regional of Valdivia was conducted. With the information provided incidence rate, mortality rate and fatality rate were calculated. Additionally, with the aim of determining prevalence of hydatidosis in livestock (i.e. cattle, sheep and pigs) official records of slaughtered animals for the same period from the Ministry of Health of Los Ríos region were searched. Results: During the ten-year period 238 new human cases were recorded, the average incidence rate for the period was 6.1 per 100,000 inhabitants, the mortality rate was 0.1 per 100,000 inhabitants, and the fatality rate was 1.3%. The most affected class group was the 15-64 years old with a 70% of cases. The districts more affected were Valdivia and Río Bueno. Most cases (54%) were from patients from rural areas, while the occupation more affected was housekeeping (29%). The liver (56%) and lungs (33%) were the localization where cysts were most frequently found. On 55% of cases, patients did not show any complication; meanwhile, infected cyst (11%) and unspecified complicated (8%) were the more frequent complication. Overall, 89% of cases recovered totally after surgery. Finally, the average in patient time was 14.7 bed-days. Prevalence of hydatidosis in livestock was 23% in cattle, 23% in sheep and 12% in pigs. The highest prevalence was found in slaughter houses in the districts of Panguipulli and San José de la Mariquina. Discussion: Human and animal hydatidosis is highly prevalent in humans and livestock in Los Ríos region compared to national and international records. Further research is recommended to assess risk factors for human infection and improving record-keeping and trazability of slaughtered animals to implement control measures at the farm level to help to stop the life cycle of the parasite and thus reduce human infections.

Objetivos y Métodos: Para determinar la prevalencia de hidatidosis humana y animal en la Región de Los Ríos durante los años 1999-2009, se realizó un análisis retrospectivo de las fichas clínicas de operados por esta enfermedad en el Hospital Clínico Regional de Valdivia. Se cuantificó morbilidad, mortalidad y letalidad y se determinaron algunas características epidemiológicas de la enfermedad. Adicionalmente, para determinar la prevalencia de equinococosis quística en el ganado, se analizaron los registros oficiales sobre la frecuencia de presentación de quistes en vísceras decomisadas en bovinos, ovinos y porcinos faenados en mataderos de la región durante el mismo período, obtenidos de la SEREMI de Salud. Resultados: Se registraron 238 casos nuevos en humanos con una tasa de incidencia promedio de 6,1 por 100 mil habs., una tasa de mortalidad de 0,1 por 100 mil habs. y una tasa de letalidad de 1,3%. En total, 53% de los casos fueron hombres y 47% mujeres. El grupo de edad entre 15 y 64 años fue el más afectado (70% del total). Las comunas con mayor número de casos fueron Valdivia y Río Bueno. Se detectaron más casos (54%) en zonas rurales que urbanas (46%). Por otro lado, la ocupación más afectada correspondió a dueñas de casa. La localización más frecuente fue hepática exclusiva (56%). Un 55% de los pacientes no mostró complicación de los quistes tratados. Después de la operación, 89% de los casos se recuperó totalmente, mientras que el período de hospitalización promedio fue de 14,7 días-cama por paciente. La prevalencia de equinococosis en ganado fue de 23% en bovinos, 23% en ovinos y 12% en porcinos. Las mayores prevalencias se reportaron en mataderos de Panguipulli y San José de la Mariquina. Discusión: La hidatidosis humana y animal son altamente prevalentes en la Región de Los Ríos comparadas con el resto del país y otras naciones. Se recomienda la realización de estudios avanzados para determinar factores de riesgo para la infección en humanos y realizar mejoras en la trazabilidad de los animales sacrificados para implementar medidas de control a nivel del predio y de esa forma cortar el ciclo del parásito y ayudar a reducir la infección en humanos.

Control programme for cystic echinococcosis in Uruguay

Cystic echinococcosis is a highly endemic parasitic zoonosis that is present in the Southern Cone countries of America. For several decades, various prevention and control programmes have been implemented in different countries and regions, with varying results. In Uruguay, a new control programme was implemented in 2006 that employed new strategies for canine diagnosis and treatment, dog population control, diagnosis in humans, epidemiological surveillance, and health education, including community participation. The control programme in Uruguay addresses the control and surveillance of the disease from a holistic perspective based on Primary Health Care, which has strengthened the community’s participation in developing and coordinating activities in an interdisciplinary manner. Similarly, the control programme that is currently implemented is based on a risk-focused approach. The surveillance and control measures were focused on small villages and extremely poor urban areas. In this study, the strategies used and the results obtained from 2008-2013 are analysed and discussed.

Echinococcus granulosus sensu lato and Taenia hydatigena in pig in southern Brazil / Echinococcus granulosus sensu lato e Taenia hydatigena em suínos no sul do Brasil

This study aimed to identify the parasitical etiologic agents of visceral cysts in pigs from the central/northern region of Rio Grande do Sul State, Brazil. Fifty-eight cysts were found in livers during veterinary inspection of swine slaughtered from January 2008 to 2012. Collected samples were submitted to macroscopic and molecular analyzes. Polymerase chain reaction (PCR), DNA sequencing and BLAST alignment of sequences was used to molecular characterization of the samples. By PCR 10.3% (6/58) of tested samples were positive for Echinococcus granulosus sensu lato and 56.9% (33/58) for Cysticercus tenuicollis. In this study, it was verified the occurrence of larval forms of E. granulosus sensu lato and Taenia hydatigena in pig herds from the central/northern region of Rio Grande do Sul State. The presence of both parasites is relevant due to the economic losses for the meat industry. Additionally, E. granulosus sensu lato has zoonotic importance and may be infecting pig herds in southern Brazil.

Neste estudo, buscou-se identificar os agentes etiológicos de origem parasitária em cistos nas vísceras de suínos oriundos sa região centro/norte do sEstado do Rio Grande do Sul, Brasil. Cinquenta e oito cistos foram encontrados durante a inspeção veterinária em fígados de suínos abatidos entre janeiro de 2008 a 2012. As amostras foram submetidas às análises macroscópicas e moleculares. Reação em cadeia da polimerase (PCR), sequenciamento de DNA e alinhamento das sequências no BLAST (bases de dados do GenBank) foram utilizados na caracterização molecular das amostras. Das amostras analisadas, 10,3% (6/58) foram positivas para Echinococcus granulosus sensu lato e 56,9% (33/58) para Cysticercus tenuicollis. Evidenciou-se a ocorrência de larvas de E. granulosus sensu lato e Taenia hydatigena em rebanhos suínos na região centro/norte do RS. A presença de ambos os agentes é relevante devido às perdas econômicas para a indústria de carnes. Além disso, destaca-se que E. granulosus sensu lato possui importância zoonótica e pode contaminar os rebanhos suínos no sul do Brasil.

Estimación del impacto económico de la equinococosis quística en Chile y análisis de las posibles causas que han dificultado su erradicación / Estimation of costs caused by cystic echinococcosis

Background: Hydatid disease or cystic echinococcosis, caused by the parasite Echinococcus granulosus, has a worldwide distribution, affecting people of working age and can cause high levels of morbidity and even death. Aim: To estimate the economic impact at the human and animal level caused by the disease in Chile. Material and Methods: We analyzed information about the disease obtained from reports and publications emanated from the Chilean Ministry of Health, United Nations Food and Agriculture Organization, the U.S. National Institute of Statistics and the National Agricultural Service. Animal derived costs were estimated evaluating the expenses for pharmacological treatment of infected dogs and animal production losses derived from confiscations and reductions in meat production. Results: The total number of patients who underwent surgery to remove a hydatid cyst in Chile during 2012, was estimated as 767 individuals. The annual costs derived only from surgical treatment, were estimated in USD 2.46 million. Summing the costs of sick leaves and loss of productivity, the costs at the human level ascended to USD 3.13 million. Considering human and animal costs, the annual economic burden of the disease was estimated in USD 14.35 million. Conclusions: The Analysis of the regional distribution of human and animal hydatidosis, suggests a significant environmental contamination with parasite eggs in high incidence regions such as Aysén, Araucanía, BioBío and Coquimbo. The efficiency of control programs for the disease would be greatly improved if the causes for these regional contaminations are elucidated.

Diagnóstico de situación de la equinococosis quística en heces dispersas en las zonas de Quebrada y Puna, provincia de Jujuy, Argentina / Diagnosis of cystic echinococcosis in faeces scattered in areas of Puna and Quebrada. Province of Jujuy, Argentina

La equinococosis es una enfermedad parasitaria común en el ganado, causada por el cestode Echinococcus granulosus; el perro es su principal hospedador definitivo. La provincia de Jujuy es un área endémica, situada en el ángulo noroeste de la República Argentina. Las condiciones ecológicas restringidas de Quebrada y Puna hacen que la actividad más importante de la población sea la pecuaria formal pastoril y trashumante, especialmente dedicada a ovinos y camélidos. El perro adquiere en estas comunidades una doble función de compañía y como pastor. El objetivo del presente estudio fue realizar un diagnóstico de situación en las áreas de Quebrada y Puna, donde se sospecha que hay circulación de E. granulosus. Desde 2002 hasta 2012 se recolectaron 523 muestras de materia fecal de canino dispersas en el ambiente. Las prevalencias variaron desde un 2 % en Susques hasta un 27,7 % (la mayor de la provincia) en Humahuaca. Tumbaya presentó una prevalencia del 21 % en 2007, llegó a 0 % en 2010, pero volvió a aumentar al 10,5 % en 2011. La disminución observada durante 2010 puede explicarse en el hecho de que las muestras se tomaron en localidades donde se había realizado educación sanitaria previamente. En el resto de las regiones estudiadas se observaron prevalencias entre 2 % y 19,4 %. Estos resultados sugieren que la falta de estrategias para el control de la equinococosis ha permitido la dispersión de la enfermedad.

Echinococcosis is a parasitic disease common in livestock, caused by the cestode Echinococcus granulosus, the dog being the principal definitive host. The province of Jujuy is an endemic area located in the Northwest of Argentina. Due to the restricted ecological conditions of Quebrada and Puna, the most important activity of the population is formal cattle pastoralism and transhumance, especially of sheep and camelids. The dog acquires the double function of company and shepherd in these communities. The objective of the present study was to conduct a diagnosis of the situation in areas of La Quebrada and Puna where the circulation of E. granulosus is suspected. Five hundred and twenty three (523) samples of canine fecal material scattered in the environment were collected from 2002 to 2012. Prevalence varied from 2% in Susques to 27.7% in Humahuaca, the largest in the province. In Tumbaya, prevalence was 21% in the year 2007, reaching 0% in the year 2010 but increasing again to 10.5% in the year 2011. These results may be related to health education on preventive measures and mass deworming held prior to sample taking in the year 2010. A prevalence between 19.4% and 2% was observed in the rest of the regions studied, suggesting that a lack of strategies for echinococcosis control has allowed the spread of the disease.

Vigilancia de la equinococosis quística en perros y niños en la provincia de Río Negro, Argentina / Cystic echinococcosis in dogs and children in the province of Río Negro, Argentina

La equinococosis quística (EQ) es una enfermedad endémica en la provincia de Río Negro, Argentina. El programa de control de esta afección desarrolla sistemas de vigilancia epidemiológica basados en las técnicas de coproELISA/Western blot (WB) en muestras de heces de perros recolectadas del suelo, a fin de determinar establecimientos ganaderos (unidades epidemiológicas o UE) con transmisión presente. El objetivo de esta investigación fue evaluar la prevalencia de EQ en establecimientos ganaderos y su relación con la presencia de casos de EQ en niños de 0 a 14 años. Se seleccionaron aleatoriamente UE donde se obtuvieron muestras de materia fecal canina, las que fueron procesadas mediante coproELISA/WB. Asimismo, se identificaron casos nuevos ocurridos en niños del rango etario señalado. Se obtuvieron 571 muestras de 278 UE; 37 (6,5 %) fueron positivas a coproELISA/WB de 37 (13,3 %) UE con transmisión presente. Las diferencias con el relevamiento efectuado en el período 2003-2004 resultaron no significativas (p = 0,9), mientras que las diferencias con el relevamiento efectuado en UE de poblaciones originarias en 2009-2010 resultaron significativas (p = 0,02). Con relación a la densidad animal en el área de trabajo, las UE que dieron un resultado negativo tuvieron un promedio de 2 (DE: 2,1) perros por UE, en las UE con infección presente el promedio fue de 3 (DE 4,2), esta diferencia fue estadísticamente significativa (p = 0,02). Se diagnosticaron 12 casos en niños menores de 15 años. Se estableció que los casos de hidatidosis, en promedio, se situaron a menor distancia de los campos positivos a coproELISA/WB que de los campos negativos (p= 0,00307). La prueba de coproELISA/WB permitió identificar la dispersión de EQ en establecimientos ganaderos y analizar su relación con la ocurrencia de casos en niños.

Cystic echinococcosis (CE) is an endemic disease in the province of Río Negro, Argentina. The control program against CE has developed monitoring surveillance systems. Currently, the coproELISA/Western blot (WB) test is used to determine transmission in livestock farms (epidemiological units or EU) from collected dry field-dispersed dog feces. The objective was to evaluate the prevalence of CE on livestock farms and its relationship with CE cases in children aged 0-14 years. Canine fecal samples were obtained from randomly selected livestock farms and processed by the coproELISA/WB test. Furthermore, new cases in children in the same age group mentioned above were identified. In 278 EU, 571 samples of canine feces were obtained. There were 37 positive samples for coproELISA/WB (6.5%) and the presence of transmission was demonstrated in 37 EU (13.3%). There were no significant differences (p=0.9) with the survey conducted in the period 2003-2004 while there were significant differences (p=0.02) with the EU survey of native populations conducted in 2009-2010. With respect to animal density in the work area, the EU yielding negative results had an average of 2 dogs (SD 2.1) per EU while in the EU having positive results the average was 3 dogs (SD 4.2), showing statistically significant differences (p=0.02). In children under 15 years of age, 12 cases were diagnosed. This study has identified, on average, that the cases of hydatid disease are closer in the positive fields than in the negative fields (p=0.00307).The coproELISA/WB test allowed to identify the dispersion of CE on livestock farms and its relationship with the occurrence of cases in children in 2009-2010.

Humoral response and evolution of Echinococcus infection in experimentally infected sheep / Resposta humoral e evolução à infecção por Echinococcus em ovinos experimentalmente infectados

There is little information on the humoral response of sheep experimentally infected with Echinococcus granulosus. Thus, the objective of this study was to evaluate this response and measure its evolution. Doses of 10, 100, 1000 and 10000 E. granulosus eggs were prepared and inoculated via intraruminal puncture. Blood samples were obtained before inoculation and every 48 h after inoculation, until they became seropositive. Thereafter, they were taken monthly for the first year and then every three months until 1700 days of observation had been completed. An ELISA test, with total hydatid fluid antigen, was used for immunodiagnosis. The average optical density of the 12 inoculated sheep was found to be above the mean cutoff value 10 days after inoculation, went on increasing until 180 days after inoculation and remained above the cutoff level until the end of the observation period. This confirms that the antibody response of sheep to E. granulosus infection occurs before production of hydatid fluid and that activation, mobilization and establishment of oncospheres in the tissues generates a persistent response from the host's immune system.

Existe pouca informação sobre a resposta imune humoral de ovinos experimentalmente infectados por Echinococcus granulosus. O objetivo deste estudo é avaliar a resposta imune por anticorpos em ovinos infectados. Os ovinos receberam doses de 10, 100, 1.000 e 10.000 ovos de E. granulosus por via intrarruminal. Amostras de sangue foram colhidas antes e após infecção, a cada 48 horas, até a detecção de anticorpos anti-E. granulosus e após, colheram-se amostras mensal e trimestralmente, no primeiro ano até 1.700 dias de infecção. No imunodiagnóstico, utilizou-se o ensaio imunoenzimático indireto (ELISA-teste) e como antígeno total, líquido hidático. Na detecção de anticorpos anti-E. granulosus no soro das 12 ovelhas, a densidade ótica esteve acima do ponto de corte, após 10 dias de infecção, aumentando até 180 dias pós-infecção, e permanecendo acima desses dias até o final do experimento. Isso confirma que a resposta por anticorpos em ovinos infectados por E. granulosus antecede a produção de líquido hidático, e que a ativação, mobilidade e permanência das oncosferas nos tecidos possibilita a resposta imune dos hospedeiros.

Detección de coproantígenos para el diagnóstico de echinococosis canina en la zona fronteriza de La Quiaca-Villazón / Coproantigens detection for the diagnosis of canine Echinococcosis in the border area of La Quiaca-Villazón

Las técnicas de inmunodiagnóstico basadas en la identificación de antígenos parasitarios en las heces secas de los perros han sido desarrolladas para la vigilancia de la echinococosis canina. En la región fronteriza de La Quiaca-Villazón, se encontraron las condiciones ambientales que favorecerían el ciclo del parásito, dada la presencia del hospedador definitivo (perro) y de hospedadores intermediarios (ovejas y cabras). La actividad más importante de la Puna es la cría de ovinos y camélidos; la faena se realiza en el campo y a manos del dueño de los ovinos, y no se aplican medidas preventivas de sanidad. El objetivo de este trabajo fue estimar la presencia de caninos parasitados por Echinococcus granulosus en esta región. Durante el año 2006 se recolectaron 168 muestras de materia fecal. En La Quiaca se tomaron muestras de las siguientes localidades: Barrios (área semirrural), Santa Catalina, Yavi Chico, El Portillo, Pumahuasi y Cara Cara (zonas rurales) y La Quiaca (área urbana). En Villazón se seleccionó el área urbana y el área semirrural de Ojo de Agua, Lampaya y Matancillas. Las muestras se analizaron por la prueba de copro-ELISA y copro-Western blot. Las localidades de San Francisco y Barrios tuvieron una prevalencia de 14,3 % y 6,7 %, respectivamente. En Villazón se encontró un 3,4 % de prevalencia en el área urbana. En Lampaya se encontró un 30 % de prevalencia. Estos resultados sugieren la necesidad de implementar estrategias para el control de la hidatidosis, tanto a nivel urbano como rural, para evitar el aumento y la dispersión de la echinococosis en la región.

Cystic Echinococcosis is a major public health issue. Immunodiagnostic techniques based on the identification of parasite antigens in dog dry faeces have been developed as alternatives for the surveillance of canine Echinococcosis. The environmental conditions favouring the parasite cycle were met in the border of La Quiaca-Villazón, given the presence of definitive (dog) and intermediate hosts (sheep and goats). The most important activity in La Puna is sheep and goat rearing; slaughtering is carried out almost exclusively in the field by sheep's owners, and preventive health measures do not apply. The aim of this study was to determine the presence of dogs parasitized by Echinococcus granulosus in this border region. A hundred and sixty eight (168) stool specimens were collected during 2006. La Quiaca samples were taken from the following selected areas: the semi-rural area of Barrios, the rural areas of Santa Catalina, Yavi Chico, El Portillo, Pumahuasi and Cara Cara and the urban area of La Quiaca; selected urban areas in Villazón and the semi-rural area of Ojo de Agua, Lampaya and Matancillas. The samples were analyzed by copro-ELISA -Western blot test. The cities of San Francisco and Barrios had a prevalence of 14.3% and 6.7%, respectively. A prevalence of 3.4% was observed in the urban area of Villazón, which indicates that dogs become infected in the rural areas and bring the risk into the city. Lampaya showed a prevalence of 30%. These findings suggest the need to implement strategies for the control of hydatidosis, both in urban and rural areas to avoid the increase and spread of Echinococcosis in the region.

Primera identificación de Echinococcus vogeli en una paca en la provincia de Misiones, Argentina / [First report of Echinococcus vogeli in a paca in Misiones province, Argentina].

We report the first finding of Echinococcus vogeli in a paca, Cuniculus paca, in the tropical forest of Misiones, in the north of Argentina. The presence of the bush dog, Speothos venaticus, E. vogelís only natural definitive host, was also reported. The polycystic hydatids, 2 to 3 cm in diameter, were only found in the liver of an adult paca. The size range of the hooks and the relative proportion blade/handle did not show significant differences with respect to the ones reported for E. vogeli. The size of E. granulosus hooks, measured for comparison purposes, was significantly smaller (p E. vogeli in Argentina. The probability of finding neotropical echinococcosis in humans reinforces the need to expand the search for E. vogeli in Argentina. Echinococcosis due to E. vogeli is very aggressive and may cause death in about a third of the human population affected.

Lesões parasitárias encontradas em bovinos abatidos para consumo humano / Parasitic lesions observed in cattle slaughtered for human consumption

During a period of 28 months (January 2011-April 2013) periodical visits were made to four cattle slaughter houses to collect samples of lesions found in cattle slaughtered for human consumption. Three hundred and three lesions were collected, 25% of which were caused by six different parasites: The metacestodes of Echinocccus granulosus (hydatid cysts), Fasciola hepatica, the metacestodes of Taenia saginata (Cysticercus bovis), Oesophagostomum radiatum, Eurythrema coelomaticum, and Paramphistomum cervi. Gross and microscopic aspects of the lesions caused by these worms are profusely illustrated and a detailed description of both pathological aspects, gross and microscopic, are provide in the hopes that the neophyte veterinary meat inspector can benefit from them in the task of recognition and interpretation of the significance of these lesion both to human and animal health. In regard to the two latter objectives, the life cycle, and the pathogenicity to the animal and human hosts, and the destination of the affected carcass or organ in the line of inspection are discussed for each parasite.

Durante um período de 28 meses (janeiro 2011-abril 2013) foram feitas visitas periódicas a quarto abatedouros frigoríficos de bovinos para colher lesões regularmente encontradas em bovinos abatidos para consumo humano. Trezentas e três lesões foram colhidas, 25% das quais eram causadas por seis parasitas diferentes: o metacestoide de Echinocccus granulosus (cisto hidático), Fasciola hepatica, o metacestoide de Taenia saginata (Cysticercus bovis), Oesophagostomum radiatum, Eurythrema coelomaticum e Paramphistomum cervi. Os aspectos macro e microscópicos causados por esses vermes são profusamente ilustrados e uma descrição macro e microscópicadas lesões é fornecida na esperança de auxiliar o inspetor de carnes iniciante na tarefa de reconhecer e interpretar o significado dessas lesões tanto para a saúde animal quanto para a saúde humana. Com respeito a esses últimos objetivos, o ciclo evolutivo, e os efeitos nos hospedeiros animal e humano, e ainda a destinação da carcaça ou órgão afetado na linha de inspeção, são discutidos para cada parasita.

Echinococcus granulosus genotypes circulating in alpacas (Lama pacos) and pigs (Sus scrofa) from an endemic region in Peru

The identification of the genotypes of Echinococcus granulosus present in livestock and wild animals within regions endemic for cystic echinococcosis (CE) is epidemiologically important. Individual strains display different biological characteristics that contribute to outbreaks of CE and that must be taken into account in the design of intervention programs. In this study, samples of hydatid cysts due to E. granulosus were collected from alpacas (4) in Puno and pigs (8) in Ayacucho in Peru, an endemic region for CE. Polymerase chain reaction amplification and DNA sequencing of specific regions of the mitochondrial cytochrome C oxidase subunit 1 and NADH dehydrogenase subunit 1 genes confirmed the presence of a strain common to sheep, the G1 genotype, in alpacas. Two different strains of E. granulosus were identified in pigs: the G1 and the G7 genotypes. This is the first report of the G1 genotype of E. granulosus in alpacas in endemic regions of CE in Peru.

Critical analysis of cystic echinococcosis control programs and praziquantel use in South America, 1974-2010 / Análisis crítico de los programas de control de la equinococosis quística y uso del prazicuantel en América del Sur, 1974-2010

Cystic echinococcosis (CE) is one of the most prevalent zoonoses in Argentina, Brazil, Chile, Peru, and Uruguay. Control programs in South America were originally modeled after programs developed in insular territories, such as Tasmania and New Zealand. The advent and proven effectiveness of praziquantel, plus the experience of insular models, produced high expectations for rapid advances; however, after 30 years of praziquantel use, no endemic area in South America has obtained eradication. In fact, only modest gains in CE control have been made and impact on prevalence among humans has been slight. A major impediment has been the infrastructure needed to administer praziquantel to dogs in rural areas 8 times per year over numerous years, a requirement for rapid attack stage 1. Such an infrastructure has not been financially or politically sustainable in endemic areas, which tend to be the poorest. On the other hand, certain areas in Argentina have had success with simple and economically viable alternatives. Based primarily on continuous field work supported by the local community, these strategies have significantly decreased transmission to humans, the health sector's main objective. In addition, new possibilities and tools, such as the EG95 vaccine, are being evaluated; as are early detection and treatment of asymptomatic carriers.

La equinococosis quística (EQ) es una de las zoonosis más prevalentes en Argentina, Brasil, Chile, Perú y Uruguay. Los programas de control en América del Sur fueron originalmente hechos a imitación de los programas desarrollados en territorios insulares, como Tasmania y Nueva Zelandia. El advenimiento y la eficacia comprobada del prazicuantel, sumados a la experiencia de los modelos insulares, dieron lugar a altas expectativas de adelantos rápidos; sin embargo, después de 30 años de uso del prazicuantel, ninguna zona endémica en América del Sur ha logrado la erradicación de la enfermedad. De hecho, solo se han obtenido avances moderados en el control de la EQ, y su repercusión sobre la prevalencia en seres humanos ha sido leve. Un impedimento mayor ha sido la infraestructura necesaria para administrar el prazicuantel a los perros en zonas rurales 8 veces por año durante varios años, un requisito para el estadio 1 de ataque rápido. Tal infraestructura no ha sido sostenible desde el punto de vista económico o político en las zonas endémicas, que tienden a ser las más pobres. Por otro lado, ciertas áreas de la Argentina han tenido éxito con opciones sencillas y económicamente viables. Basadas principalmente en el trabajo continuo en el terreno apoyado por la comunidad local, estas estrategias han reducido significativamente la transmisión a los seres humanos, que es el objetivo principal del sector de la salud. Además, se están evaluando nuevas posibilidades y herramientas, como la vacuna EG95, al igual que la detección temprana y el tratamiento de los portadores asintomáticos.

Molecular characterization of Echinococcus granulosusfrom Peru by sequencing of the mitochondrial cytochrome C oxidase subunit 1 gene

Echinococcus granulosus, the etiologic agent of cystic echinococcosis (CE) in humans and other animal species, is distributed worldwide. Ten intra-specific variants, or genotypes (G1-G10), have been defined based on genetic diversity. To determine the genotypes present in endemic areas of Peru, samples were collected from cattle (44), sheep (41) and humans (14) from Junín, Puno Huancavelica, Cusco, Arequipa and Ayacucho. DNA was extracted from protoscolex and/or germinal layers derived from 99 E. granulosus isolates and used as templates to amplify the mitochondrial cytochrome C oxidase subunit 1 gene. The resulting polymerase chain reaction products were sequenced and further examined by sequence analysis. All isolates, independent of the host, exhibited the G1 genotype. Phylogenetic analysis showed that three isolates from Ayacucho shared the same cluster with microvariant G1(4). The G1 genotype is considered the most widespread and infectious form of E. granulosusworldwide and our results confirm that the same patterns apply to this country. Therefore, these findings should be taken into consideration in developing prevention strategies and control programs for CE in Peru.

Fisiopatología y respuesta inmune de ovinos experimentalmente infectados con Echinococcus granulosus / Pathophysiology and immune response in sheep experimentally infected with Echinococcus granulosus

La respuesta inmune a la infección por Echinococcus granulosus en el ovino ha sido poco estudiada. El objetivo del presente trabajo fue aportar información sobre la fisiopatología y la respuesta inmune a la infección experimental con E. granulosus en ovinos. Se inocularon experimentalmente ovinos con tres dosis distintas de huevos de E. granulosus, evaluándose la repuesta inmune por seguimiento mediante enzimo inmuno ensayo con tres preparaciones antigénicas (líquido hidatídico total, fracción purificada de líquido hidatídico total y fracción lipoproteica purificada) durante 500 días. Se sacrificaron animales en forma escalonada para observar macroscópica y microscópicamente el desarrollo del parásito. La respuesta inmune se detectó a partir de los 10 días y se mantuvo durante el período de observación, resultando inicialmente proporcional a la carga de huevos inoculados, y disminuyendo las diferencias con el tiempo. Se identificaron quistes fértiles a los 10 meses post inoculación y oncósferas vivas 500 días post inoculación. La respuesta de anticuerpos en el ovino a la infección por E. granulosus fue anterior a la formación de líquido hidatídico y resultó generada por la movilidad de la oncósfera. La temprana fertilidad identificada histológicamente indica que la alimentación de canes con vísceras de ovinos jóvenes puede producir ciclos de infección. La presencia de oncósferas vivas en el hígado, por su parte, aporta información sobre la patogenia de la enfermedad y permite expresar hipótesis sobre las causas de nuevas operaciones en el hombre luego de la extirpación de un quiste hidatídico lo que podría liberar el freno inmunitario sobre dichas oncósferas.

The immune response to Echinococcus granulosus in sheep has not been extensively investigated. The objective of this study was to increase the information on the physiopathology of E. granulosus and the immune response elicited in sheep. Animals were experimentally inoculated with three different doses of E. granulosus eggs and the immune response was evaluated over 500 days using enzyme immunoassay with three antigenic preparations: total hydatid fluid, purified fraction of hydatid fluid and purified lipoprotein fraction. Sheep were slaughtered at different intervals to observe the macroscopic and microscopic development of the parasite. Immune response was detected at 10 days and was maintained throughout the observation period, being initially proportional to the load of inoculated eggs and then decreasing over time. Fertile cysts were identified 10 months after inoculation and live onchosphere 500 days after inoculation. Antibody response to E. granulosus in sheep preceded hydatid fluid formation and was generated by the mobility of the onchosphere. Early histological identification of fertile cysts indicates that feeding dogs with viscera of young sheep can produce cycles of infection. Furthermore, the presence of live onchosphere in the liver here found contributes to a better knowledge of the pathogenesis of this disease it could be hypothetically considered as a cause for the repeated surgeries necessary in man after the extirpation of a hydatid cyst.

Cystic echinococcosis in southern Brazil / Equinococose cística no sul do Brasil

Cystic echinococcosis (CE) is very common in the southern part of Rio Grande do Sul State where sheep and cattle raising is the most important economical activity. Prevalence in intermediate hosts is well known due to reports in slaughterhouses while human reports are of discussed value. This is due to underreporting of cases and few epidemiological studies make it difficult to assess the situation of echinococcosis in the population. Whereas cattle infection rate is more or less stable around 12 percent of the slaughter animals, in sheep there has been an increasing number in the last five years. Some efforts have been done to control the zoonosis but no effective results were obtained so far. Probably educational efforts to change human practices (feeding dogs with raw viscera), periodic treatment of dogs with praziquantel and joined actions with slaughterhouses could bring more attention to improve some control measures.

A equinococose cística (CE) é muito comum na região sul do estado do Rio Grande do Sul, onde a criação de bovinos e ovinos representa a maior atividade econômica. A prevalência nos hospedeiros intermediários é bem conhecida devido aos registros em frigoríficos enquanto que os casos humanos apresentam dados discutíveis e de difícil interpretação. Isto é devido a subnotificação e os poucos estudos epidemiológicos tornam difícil a avaliação da equinococose na população. Enquanto que a prevalência em bovinos estabilizou ao redor de 12 por cento de animais abatidos na última década, em ovelhas está ocorrendo um aumento nos últimos cinco anos. Algumas tentativas estão sendo feitas para controlar esta zoonose mas não tem sido obtidos resultados práticos até agora. Provavelmente ações educativas que alterem comportamentos humanos (alimentação de cães com vísceras cruas), tratamento periódico dos cães com praziquantel e ações junto a frigoríficos poderiam resultar em incremento nas medidas de controle devido às perdas econômicas mensuráveis.