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Fil: Crowley Pablo, Uiversidad Nacional de Rio Negro, Escuela de Veterinaria, Rio Negro, Argentina Fil: Labanchi Jose Luis, Universidad Nacional de Rio Negro, Escuela de Veterinaria, Rio Negro, Argentina Fil: Dade Mertin, Universidad Nacional de Rio Negro, Escuea de Veterinaria, Rio Negro Fil: Daniele Martin, Universidad Nacional de Rio Negro, Escuela de Veterinaria, Rio Negro Fil: Calabro Arnoldo, Ministerio de Salud, Salud Ambiental, Rio Negro Fil: Grizmado Claudia, Ministerio de Salud, Salud Ambiental, Rio Negro Fil: Ochoa Alexis, Universidad Nacional de Rio Negro, Escuela de Veterinaria, Rio Negro Fil: Hernandez Paula, Ministerio de Salud, Salud Ambiental, Rio Negro Fil: Arezo Marcos, Ministerio de Salud, Salud Ambiental, Rio Negro Fil: Larrieu Edmundo, Universidad Nacional de Rio Negro, Escuela de Veterinaria, Rio Negro Chagas is an endemic epidemic disease of vector transmission in the Province of Rio Negro caused by Trypanosoma cruzi, transmitted by triatomines. The Chagas control program certified, through serological and entomological indicators, the interruption of vector transmission throughout the provincial territory. However, in recent years, conditions have been generated that may allow the re-emergence of the disease, such as the eventual domiciliation of wild vinchucas such as T patagonico. The objective was to evaluate the epidemiological situation of the vector through studies of home and peri-home infestation by triatomines and to carry out resistance analyzes to insecticides that were applied for many years in control. As a result, 143 homes were evaluated and 66 light traps were placed. In the intra-domicile all the dwellings were negative, with 3 being positive in the peri-domicile (2.1%) with captures of T-infestans and T. patagonica. No triatomines were captured with the light traps. The captured triatomines were T. infestans and T. patagonica, which were all negative for T. cruzi. Insecticide resistance studies showed that the colonies are still susceptible to deltamethrin. Chagas es una enfermedad endemoepidémica de transmisión vectorial en la Provincia de Rio Negro causada por Trypanosoma cruzi, transmitido por insectos vectores denominados triatominos (vinchucas). El programa de control de Chagas certifico, a través de indicadores serológicos y entomológicos la interrupción de la transmisión vectorial en todo el territorio provincial. Sin embargo, en los últimos años se han generado condiciones que pueden posibilitar la reemergencia de la enfermedad, tal como la eventual domiciliación de vinchucas silvestres como Triatoma patagónica. El objetivo fue evaluar la situación epidemiológica del vector mediante estudios de infestación domiciliaria y peri domiciliaria por triatominos y efectuar análisis de resistencia al principal insecticida que fue aplicado durante muchos años en control. Como resultado se evaluaron 143 viviendas y se colocaron 66 trampas de luz. En el introdomicilio todas las viviendas resultaron negativas, resultando 3 positivas en el peri-domicilio (2.1%) con capturas de T- infestans y T. patagonica. Con las trampas de luz no se capturaron triatominos. Los insectos capturados fueron T. infestans y T. patagonica los que resultaron todos negativos a T. cruzi. Los estudios de resistencia a insecticidas mostraron que las colonias siguen siendo susceptibles a deltametrina.

Se efectuo una busqueda bibliografica exhaustiva sobre epidemiologia, vigilancia epidemiologica y estrategias de control de Rabia variante 4 transmitida por murcielagos insectivoros. Asimismo, como estudio de caso se efectuo un estudio retrospectivo de murcielagos insectivoros capturados por vigilancia pasiva y analizados para determinar presencia de virus rabico en la Provincia de Rio Negro, Argentina. El objetivo fue actualizar la informacion sobre la epidemiologia de la rabia variante 4 y analizar la eficacia de las medidas de control habitualmente recomendadas por los servicios de salud. La revision efectuada muestra en Sudamerica solo 5 notificaciones correspondientes a caninos y felinos entre 2009 y 2019 y en relacion a las personas, se reportaron tres casos: en Chile en 1963 y 2013 y uno en Colombia en 2012. La identificacion de murcielagos insectivoros portadores de rabia varia del del 4% al 15%. Por su parte, el servicio de salud publica veterinaria del Ministerio de Salud de Rio Negro recogio murcielagos insectivoros a partir de actividades de vigilancia pasiva. Los murcielagos fueron remitidos al Laboratorio del Instituto Luis Pasteur de la ciudad de Buenos Aires para identificacion de virus rabico. Se analizaron un total de 294 quiropteros insectivoros en 26 localidades. La proporcion de infectados fue del 14,6% (IC95% 9,5-17,8) aunque sin casos en perros, gatos o personas. Los murcielagos insectivoros pueden ser un factor de riesgo para caninos, felinos y seres humanos, aunque las notificaciones de casos a variante 4 en estas especies es extremadamente bajo en America del Sur por lo que parece requerirse una evaluacion de la estrategia de control recomendada y aplicada hasta el momento por no ser costo - efectiva, e implicar crecientes costos operativos en recursos financieros y humanos, proponiendose alternativas mas eficientes de control de riesgos.

In December 2019, an outbreak of a novel zoonotic coronavirus began, called SARS-CoV-2 or COVID-19, which reached pandemic dimensions on March 11, 2020. By March 3, it had already entered República Argentina, while on March 9 the first case occurred in the Province of Rio Negro. In this province, 823 cases were identified with 41 deaths and 602 recovered cases by June 30, giving rise to successive intervention strategies to prevent its arrival in some places without viral circulation, to control outbreaks occurred and, when this objective was achieved, to avoid reintroduction. Among all measures, those related to non-pharmaceutical Interventions or NFI based on Primary Health Care and One Health with integrated participation among health agents of the First Level of Care, veterinary public health and medical areas of the Departments of Activities for the Area and Its Primary Health Care Centers and epidemiology services are a central, highly effective and essential strategy to cut the transmission chain and decrease the agent’s reproductive capacity (R0) to a value

Objective. To compare the performance of polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) tests for diagnosing Echinococcus granulosus in dog feces among national reference laboratories in Argentina, Chile, Peru, and Uruguay. Methods. National laboratories affiliated with the Ministry of Health/Agriculture of each country exchanged panels of 10 positive/negative samples obtained from their regular national surveillance programs in November 2015 – November 2016. All laboratories applied PCR; two also applied ELISA techniques. Sensitivity and specificity were determined for each laboratory and concordance of results among the laboratories was evaluated by Cohen Kappa coefficient. Results. Poor concordance (3 of 10 paired comparisons had values of Kappa > 0.4), low sensitivity and specificity across all laboratories, and poor performance of both techniques in detecting E. granulosus in canine feces was demonstrated in this study. An ex-post comparison of the laboratories’ test protocols showed substantial heterogeneity that could partially explain poor concordance of results. Conclusion. The results underscore the heterogeneity of canine echinococcosis diagnosis across the region and indicate possible sources of variability. Efforts to standardize canine echinococcosis testing must be included in the plan of action for the Regional Initiative for the Control of Cystic Echinococcosis. Future comparisons with fecal samples of known parasite load are needed.

Cystic echinococcosis (CE) is a zoonosis caused by species of the complex Echinococcus granulosus, sensu lato in their larval stage. It is an endemic disease in the province of Río Negro, where small farmers generally have both sheep and goats. Lamb vaccination with EG95 was incorporated in 2009 with very good results: in fact, it contributed to a significant drop in prevalence of infection in both sheep and goats, when determined by necropsy and serology in 2018. In the design of the activity, it was decided not to vaccinate goats in order to minimize the operational requirements of vaccination and comments from producers about the rarity of observing hydatid cysts in goat viscera were considered.To identify causes which can still generate infection in dogs, and to detect species/genotypes in circulation in the province of Río Negro.In indigenous reserves comprised within the area of lamb vaccination with 3 doses of EG95, (dose 1 in December, dose 2 in January and dose 3 in December of the year following, at the time of application of dose 1 to the new lambs). Prevalence in adult goats and sheep was determined by necropsy and serology (ELISA). Infective species/genotypes present in the work area and in the rest of the province of Río Negro were identified by Cox1 mitochondrial gene sequencing. Epidemiological analysis was completed with surveys among farmers about slaughter habits for human consumption.Through serology and necropsy, infection rates in vaccinated and nonvaccinated sheep were significantly different (21% versus 66%). Non-vaccinated sheep and non-vaccinated goats were also significantly different in that there was less infection in goats compared to sheep (7% versus 66% for necropsy, 30% versus 61% for serology); After many years of sheep vaccination the infection positives were low, and differences between vaccinated sheep and non-vaccinated goats turned out non-significant (21% versus 7%). With reference to epidemiology and control along the period 2018-2022, PZQ dosing of dogs 4 times a year was maintained, and 2 extra deworming tasks were introduced together with dose 1 and 2 of EG95, performed by the veterinary vaccination team, ensuring the ingestion of PZQ by dogs. Assessment of animal slaughter for consumption in 41 producers showed that 21 of them slaughter a monthly average of 18 goats (an average of 0.43 goat per month per farm) and 36 in all slaughter 35 old sheep in a year (average of 0.85 sheep per month per farm). With respect to identification of species/genotypes as from 2010, genotypes G1 have been found in 11 sheep (out of which 6 belong to vaccination zone) and genotypes G7, in one pig. A goat cyst within vaccination zone turned out unfertile and it was not possible to sequence it.Design and implementation of a vaccine programme combined with the use of PZQ resulted as cost-effective, since it was possible to maintain the vaccine over time, with clear impact on prevalence decrease in sheep and goats.

Echinococcus granulosus sensu lato is a globally prevalent zoonotic parasitic cestode leading to cystic echinococcosis (CE) in both humans and sheep with both medical and financial impacts, whose reduction requires the application of a One Health approach to its control. Regarding the animal health component of this approach, lack of accurate and practical diagnostics in livestock impedes the assessment of disease burden and the implementation and evaluation of control strategies. We use of a Bayesian Latent Class Analysis (LCA) model to estimate ovine CE prevalence in sheep samples from the Río Negro province of Argentina accounting for uncertainty in the diagnostics. We use model outputs to evaluate the performance of a novel recombinant B8/2 antigen B subunit (rEgAgB8/2) indirect enzyme-linked immunosorbent assay (ELISA) for detecting E. granulosus in sheep. Necropsy (as a partial gold standard), western blot (WB) and ELISA diagnostic data were collected from 79 sheep within two Río Negro slaughterhouses, and used to estimate individual infection status (assigned as a latent variable within the model). Using the model outputs, the performance of the novel ELISA at both individual and flock levels was evaluated, respectively, using a receiver operating characteristic (ROC) curve, and simulating a range of sample sizes and prevalence levels within hypothetical flocks. The estimated (mean) prevalence of ovine CE was 27.5% (95%Bayesian credible interval (95%BCI): 13.8%–58.9%) within the sample population. At the individual level, the ELISA had a mean sensitivity and specificity of 55% (95%BCI: 46%–68%) and 68% (95%BCI: 63%–92%), respectively, at an optimal optical density (OD) threshold of 0.378. At the flock level, the ELISA had an 80% probability of correctly classifying infection at an optimal cut-off threshold of 0.496. These results suggest that the novel ELISA could play a useful role as a flock-level diagnostic for CE surveillance in the region, supplementing surveillance activities in the human population and thus strengthening a One Health approach. Importantly, selection of ELISA cut-off threshold values must be tailored according to the epidemiological situation., Highlights • Development of a Bayesian LCA model for ovine cystic echinococcosis (CE) in Argentina. • Evaluation of diagnostic performance for a novel rEgAgB8/2 indirect ELISA. • Identification of optimal ELISA thresholds for use as a flock-level surveillance tool. • Improvement of CE surveillance in sheep will help strengthen the One Health approach.

Background Cystic echinococcosis (CE) is a parasitic zoonosis caused by infection with the larval stage of Echinococcus granulosus (s.l.). This study investigated the prevalence and potential risk factors associated with human CE in the towns and rural areas of Ñorquinco and Ramos Mexia, Rio Negro province, Argentina. Methods To detect abdominal CE cysts, we screened 892 volunteers by ultrasound and investigated potential risk factors for CE using a standardized questionnaire. Prevalence ratio (PR) with 95% confidence intervals (CI) was used to measure the association between CE and the factors investigated, applying bivariate and multivariate analyses. Results Abdominal CE was detected in 42/892 screened volunteers (4.7%, 95% CI 3.2–6.1), only two of whom were under 15 years of age. Thirteen (30.9%) CE cases had 25 cysts in active stages (CE1, CE2, CE3a, according to the WHO Informal Working Group on Echinococcosis [WHO-IWGE] classification). The most relevant risk factors identified in the bivariate analysis included: living in rural areas (P = 0.003), age > 40 years (P = 0.000), always drinking water from natural sources (P = 0.007), residing in rural areas during the first 5 years of life (P = 0.000) and having lived more than 20 years at the current address (P = 0.013). In the multivariate final model, the statistically significant risk factors were: frequently touching dogs (P = 0.012), residing in rural areas during the first 5 years of life (P = 0.004), smoking (P = 0.000), age > 60 years (P = 0.002) and living in rural areas (P = 0.017). Conclusions Our results point toward infection with CE being acquired since childhood and with constant exposure throughout life, especially in rural areas with a general environmental contamination. Graphical Abstract

Cystic echinococcosis (CE), caused by Echinococcus granulosus, is a chronic and debilitating zoonotic larval cestode infection in humans, which is principally transmitted between dogs and domestic livestock, particularly sheep. Human CE occurs in almost all pastoral communities and rangeland areas of the underdeveloped and developed world. Control programmes against CE have been implemented in several endemic countries to reduce or eliminate the disease. New Zealand and Tasmania are examples of some of the first programmes to be undertaken (in insular territories) and which were very successful in the elimination of CE. The advent and proven effectiveness of praziquantel, plus the experience of insular models, produced high expectations for rapid advances in a second generation of control programmes undertaken in continental areas (Argentina, Uruguay and Chile). Nevertheless, only moderate gains in CE control have been made and the impact on prevalence among humans has been slight. A major impediment to the adoption of procedures that were successful in New Zealand and Tasmania has been the requirement to administer praziquantel to dogs in rural areas eight times per year over numerous years. In addition, there have been clear technological improvements made in the diagnosis of canine echinococcosis for surveillance, the genetic characterization of parasite strains and in vaccination against CE infection in livestock. In order to establish new paradigms and appropriate combinations of control strategies, we have carried out a review and discussion of the available control tools and control models. Control strategies must be suitable and sustainable to benefit the Echinococcosis-endemic areas primarily, which at the same time are the poorest regions of the world.

Cystic echinococcosis (CE) is endemic in the Rio Negro province of Argentina. After 30 years of control using praziquantel in dogs the transmission rate to humans and sheep has decreased significantly, however transmission persists. The objective of the study was to assess the inclusion of the EG95 for sheep in the control program and to determine the vaccine's operative feasibility in field conditions. An intervention study was defined in Rio Negro Province in Argentina comprising, in total, an area of 5820 Km2. Lambs received two vaccinations with the EG95 vaccine followed by a single booster injection when the animals were 1-1.5 years of age. Vaccination of lambs born into one trial site was introduced and continued for 8 years. Evidence for Echinococcus granulosus transmission was monitored before and after vaccination by coproantigen ELISA in faecal samples of dog, purgation of dogs to detect E. granulosus worms, necropsy on adult sheep and by ultrasound screening in children of 6-14 years old. 29,323 doses of vaccine were applied between 2009 and 2017, which a vaccination coverage of 80.1%/85.7% (57.3% average for fully vaccinated). Before the introduction of the vaccine 56.3% of the 6-year-old sheep were infected with E. granulosus at necropsy and 84.2% of the farms had infected sheep; 4.3% of the dogs were positive for E. granulosus infection using the arecoline test, and with coproELISA 9.6% of dog fecal samples were positive and 20.3% of the farms had infected dog.After the vaccine was introduced, 21.6% of sheep older than 6 years were found to be infected at necropsy and 20.2% of the farms were found to be infected; in dogs, 4.5% were found positive for E. granulosus using arecoline purgation and with coproELISA 3.7% of samples were positive, with 8.9% of farms having a positive dog. In 2016 only one case of E. granulosus infection was diagnosed by US screening in a 6-14 years old child. Included in the analysis are discussions of difficulties experienced in the field which affected correct vaccine administration as well as social features and practices that may impact on echinococcosis control and the EG95 vaccination program in Rio Negro. Vaccination of sheep with the EG95 vaccine provides a valuable new tool which improves the effectiveness of CE control activities. Vaccination was effective even in a difficult, remote environment where only approximately half the lambs born into the communities were fully vaccinated.

Background Rio Negro Province is endemic for cystic echinococcosis (CE). A CE control program includes early diagnosis in humans. During 1980-1996, screening was done with serology and surgery was the unique choice of treatment. Since 1997, ultrasound (US) has been the method of choice for screening, and new choices of treatment for asymptomatic carriers are discussed in the CE guidelines. Methods Between 1997 and 2016, 42 734 abdominal USs were performed, 192 new asymptomatic cases were diagnosed and underwent a protocol according to the size, location and type of cyst. Treatment options included active surveillance (US monitoring, 83 [43.3%]), antiparasitic (albendazole, 92 [47.9%]) and surgery (17 [8.8%], including percutaneous treatment). Results After 7.7 y of follow-up, of the cases under active surveillance, 28 (33.7%) had to change treatment: 5 (6%) to surgery and 22 (26.5%) to albendazole. Of the patients treated with albendazole, 3 (3.2%) were operated on and 13 (14%) were treated with a second cycle of albendazole. Conclusion As a result of the present study, resolution of CE in a non-surgical way with albendazole is confirmed to be effective in asymptomatic carriers with CE1 or CE3a cysts. An update eliminates the strategy of active surveillance in type CE1 cysts

Background: Cystic echinococcosis (CE) is a parasitic zoonosis caused by infection with the larval stage of Echinococcus granulosus sensu lato This study investigated the prevalence and potential risk factors associated with human CE in the towns and rural areas of Ñorquinco and Ramos Mexia, Rio Negro province, Argentina. Methods: In order to detect abdominal CE cysts, we screened 892 volunteers by ultrasound and investigated potential risk factors for CE using a standardized questionnaire. Bivariate and multivariate analyses were used to estimate the Prevalence Ratio (PR) and their 95% CIs of the association between CE and the factors investigated. Results: Abdominal CE was detected in 42/892 screened volunteers (4.7%, CI 3.2-6.1), only two of who being under 15 years of age. Thirteen CE (30.9%) cases had 25 cysts in active stages (CE1, CE2, CE3) The most relevant risk factors identified in the bivariate analysis included: live in rural area (p=0.003), age >40 years (p=0.000), drinking always water of natural source (p=0.007), residing in rural areas during first five years of life (p=0.000) and live more than 20 years at your current address (p=0.013). In the multivariate model, statistically significant risk factors were: frequently touch dogs (p=0.012), residing in rural areas during first five years of life (p=0.004), smoking (p=0.000), age > 60 years (p­­=0.002) and live in rural areas (p=0.017).Conclusions: our results point toward infection with CE being acquired since childhood and with constant exposure throughout life, especially in rural areas with a general environmental contamination

The analysis of zoonotic disease risk requires the consideration of both human and animal geo-referenced disease incidence data. Here we show an application of joint Bayesian analyses to the study of echinococcosis granulosus (EG) in the province of Rio Negro, Argentina. We focus on merging passive and active surveillance data sources of animal and human EG cases using joint Bayesian spatial and spatio-temporal models. While similar spatial clustering and temporal trending was apparent, there appears to be limited lagged dependence between animal and human outcomes. Beyond the data quality issues relating to missingness at different times, we were able to identify relations between dog and human data and the highest ‘at risk’ areas for echinococcosis within the province., Author summary This work focuses on utilizing animal disease data to try and inform our understanding of the spread of diseases in humans. We implement predictive models to estimate the relationship between the distribution of disease in animal populations and the distribution of disease in human populations. Development of a better understanding of this relationship could inform animal and public health interventions aiming to mitigate against human disease before it spreads. Missing data and limited data resources made discovery of these relationships difficult, but we fit multiple model types to try and identify any connection between these two populations. We found specific areas with elevated risk of human disease and changes in disease risk over time. Finally, there was some indication of an association between previous years’ levels of animal disease and human disease when using animals as covariables.

Objective: Cystic echinococcosis (CE) is a parasitic zoonosis caused by Echinococcus granulosus sensu lato. Immunodiagnostic techniques such as Western blot (WB) or enzyme-linked immunosorbent assay (ELISA), with different antigens, can be applied to the diagnosis of sheep for epidemiological surveillance purposes in control programs. However, its use is limited by the existence of antigenic cross-reactivity between different species of taeniidae present in sheep. Therefore, the usefulness of establishing surveillance systems based on the identification of infection present in a livestock establishment, known as the (Epidemiological) Implementation Unit (IU), needs to be evaluated. Materials and Methods: A new ELISA diagnostic technique has been recently developed and validated using the recombinant EgAgB8/2 antigen for the detection of antibodies against E. granulosus. To determine detection of infection at the IU level using information from this diagnostic technique, simulations were carried out to evaluate the sample size required to classify IUs as likely infected, using outputs from a recently developed Bayesian latent class analysis model. Results: Relatively small samples sizes (between 14-29) are sufficient to achieve a high probability of detection (above 80%), across a range of prevalence, with the recently recommended Optical Density cut-off value for this novel ELISA (0.496), which optimizes diagnostic sensitivity and specificity. Conclusions: This diagnostic technique could be potentially used to identify the prevalence of infection in an area under control, measured as the percentage of IUs with the presence of infected sheep (infection present), or to individually identify the IU with ongoing transmission, given the presence of infected lambs, on which control measures should be intensified.

Cystic echinococcosis is endemic in the Rio Negro province of Argentina and, for this, a control program using praziquantel in dogs was developed from 1980. The transmission rate to humans and sheep has decreased significantly, however transmission persists. In 2009 the vaccination of sheep with EG95 was incorporated in some areas of the province. The objective of the study was to evaluate the humoral responses to the vaccine EG95. Lambs received two vaccinations with the EG95 vaccine followed by a single booster injection when the animals were 1-1.5 years of age. Blood samples from 6 vaccinated groups and 4 no vaccinated sheep were obtained for determination of antibody titles against EG95 protein. Anti-EG95 responses were determined as described by Heath and Koolaard, 2012. Responses were evaluated from 331 animals. Median ELISA absorbance values in vaccinated group was 0.828, and in non-vaccinated groups was 0.218. EG95 antibody responses in sheep from different cohorts of non-immunized control groups and vaccinated groups reveal the sustained increase in response seen in animals following the third immunization. (p< 0.0001). Significant differences are also evidenced in ANOVA test (p< 0.001). An anti-EG95 antibody response was induced in all groups of immunized sheep, 4 times higher (0.828) than the mean observed in the control groups (0.218). Data described here indicate that following a third vaccination with the EG95 vaccine at 1 year of age the specific IgG responses detected in the serum of sheep increased to a level greater than that seen following the second immunization and that this response was maintained longitudinally over time, for at least 5 years. Fil: Larrieu, Edmundo Juan. Universidad Nacional de La Pampa. Facultad de Ciencias Veterinarias; Argentina. Universidad Nacional de Río Negro; Argentina Fil: Poggio, Thelma Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología "Dr. César Milstein". Fundación Pablo Cassará. Instituto de Ciencia y Tecnología ; Argentina Fil: Mujica, Guillermo. Provincia de Río Negro. Ministerio de Salud; Argentina Fil: Gauci, Charles G.. University of Melbourne; Australia Fil: Labanchi, Jose Luis. Provincia de Río Negro. Ministerio de Salud; Argentina Fil: Herrero, Eduardo. Provincia de Río Negro. Ministerio de Salud; Argentina Fil: Araya, Daniel. Provincia de Río Negro. Ministerio de Salud; Argentina Fil: Grizmado, Claudia. Provincia de Río Negro. Ministerio de Salud; Argentina Fil: Calabro, Arnoldo. Provincia de Río Negro. Ministerio de Salud; Argentina Fil: Talmon, Gabriel. Provincia de Río Negro. Ministerio de Salud; Argentina Fil: Crowley, Pablo Ernesto. Universidad Nacional de Río Negro; Argentina Fil: Santillán, Graciela. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr. C. G. Malbran". Departamento de Parasitología; Argentina Fil: Vizcaychipi, Katherina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr. C. G. Malbran". Departamento de Parasitología; Argentina Fil: Seleiman, Marcos. Provincia de Río Negro. Ministerio de Salud; Argentina Fil: Sepulveda, Luis. Provincia de Río Negro. Ministerio de Salud; Argentina Fil: Arezo, Marcos. Provincia de Río Negro. Ministerio de Salud; Argentina Fil: García Cachau, Mariela Alejandra. Universidad Nacional de La Pampa. Facultad de Ciencias Veterinarias; Argentina Fil: Lamberti, Roberto. Universidad Nacional de La Pampa. Facultad de Ciencias Veterinarias; Argentina Fil: Molina, Leonardo. Universidad Nacional de La Pampa. Facultad de Ciencias Veterinarias; Argentina Fil: Gino, Lilia Mabel. Universidad Nacional de La Pampa. Facultad de Ciencias Veterinarias; Argentina Fil: Donadeu, Meritxell. University of Melbourne; Australia Fil: Lightowlers, Marshall W.. University of Melbourne; Australia

To compare the performance of polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) tests for diagnosingNational laboratories affiliated with the Ministry of Health/Agriculture of each country exchanged panels of 10 positive/negative samples obtained from their regular national surveillance programs in November 2015 - November 2016. All laboratories applied PCR; two also applied ELISA techniques. Sensitivity and specificity were determined for each laboratory and concordance of results among the laboratories was evaluated by Cohen Kappa coefficient.Poor concordance (3 of 10 paired comparisons had values of Kappa0.4), low sensitivity and specificity across all laboratories, and poor performance of both techniques in detectingThe results underscore the heterogeneity of canine echinococcosis diagnosis across the region and indicate possible sources of variability. Efforts to standardize canine echinococcosis testing must be included in the plan of action for the Regional Initiative for the Control of Cystic Echinococcosis. Future comparisons with fecal samples of known parasite load are needed.Comparar el rendimiento de los ensayos de la reacción en cadena de la polimerasa y el enzimoinmunoanálisis de adsorción en fase sólida (o ELISA, por su sigla en inglés) para diagnosticarLos laboratorios nacionales, afiliados a los ministerios de salud y agricultura y ganadería de cada país, intercambiaron paneles de diez muestras positivas y negativas obtenidas de sus respectivos programas nacionales de vigilancia desde el mes de noviembre del año 2015 hasta el mismo mes del año siguiente. Todos los laboratorios emplearon la reacción en cadena de la polimerasa y dos emplearon también técnicas de ensayo inmunoenzimático (ELISA). Se determinó la sensibilidad y la especificidad de cada laboratorio y se evaluó la concordancia entre los resultados de los laboratorios mediante el coeficiente kappa de Cohen.Este estudio descubrió una escasa concordancia (3 de 10 comparaciones de pares obtuvieron valores de kappa0,4), una sensibilidad y especificidad bajas en todos los laboratorios y un rendimiento deficiente de ambas técnicas de diagnóstico deLos resultados subrayan la heterogeneidad del diagnóstico de equinococosis canina en toda la región e indican posibles fuentes de esta variabilidad. Deben incluirse medidas para estandarizar la prueba de equinococosis canina en el plan de acción de la Iniciativa Sudamericana para el Control de la Equinococosis Quística. En el futuro serán necesarias comparaciones adicionales con muestras fecales con una carga de parásitos conocida.Comparar o desempenho dos métodos de reação em cadeia da polimerase (PCR) e ensaio imunoenzimático (ELISA) no diagnóstico de infecção peloLaboratórios nacionais conveniados ao Ministério da Saúde/Agricultura de cada país participante intercambiaram grupos de 10 amostras positivas/negativas coletadas rotineiramente pelos programas nacionais de vigilância no período de novembro de 2015 a novembro de 2016. Todos os laboratórios empregaram o método de PCR e dois empregaram também o método de ELISA. A sensibilidade e a especificidade dos métodos foram determinadas em cada laboratório, e a concordância dos resultados entre os laboratórios participantes foi avaliada com o coeficiente kappa de Cohen.Observou-se fraca concordância (3 de 10 comparações pareadas com kappa0,4), baixa sensibilidade e especificidade e fraco desempenho de ambos os métodos na identificação doOs resultados deste estudo apontam para a falta de uniformidade no diagnóstico de equinococose canina em toda a Região e indicam possíveis causas para variabilidade. A padronização da análise laboratorial da equinococose canina deve constar do plano de ação para a Iniciativa Regional para Controle da Hidatidose. Outras comparações de amostras fecais de parasitas conhecidos devem ser realizadas.

Cystic echinococcosis (CE), a parasitic zoonosis with substantial human health and economic consequences, is highly endemic in Rio Negro Province, Argentina. The objective of this study was to estimate the direct and indirect human and livestock-associated monetary losses attributable to CE, in Rio Negro Province, for the year 2010. Human costs were estimated using data obtained from hospital chart reviews, patient interviews, and government reports. Livestock-associated losses were estimated using data from government reports and scientific publications. Spreadsheet models were developed utilizing Latin Hypercube sampling to account for uncertainty in the input parameters. In 2010, the estimated total cost of CE, in Rio Negro Province, ranged from US$4,234,000 (95% credible interval [CI]: US$2,709,000-US$6,226,000) to US$5,897,000 (95% CI: US$3,452,000-US$9,105,000), with livestock-associated losses representing between 80% and 94% of the total losses, depending on whether non-healthcare-seeking human cases were included and if livestock slaughter values were adjusted to account for underreporting. These estimates suggest that CE is responsible for considerable human and livestock-associated monetary losses in Rio Negro Province. Stakeholders and policymakers can use these data to better allocate public health and agricultural resources for this region.

Cystic echinococcosis (CE) is a parasitic zoonosis caused by Echinococcus granulosus. The control program of CE of Rio Negro province, Argentina, involves annual surveillance using ultrasound (US) screening in school children, and five-year cross-sectional surveys to detect livestock farms with parasitized dogs by coproELISA with confirmation tests (Western Blot or PCR). Control program is based on deworming of dogs with praziquantel and the aim is to identify areas at risk of Cystic echinococcosis transmission to humans, using all available data sources. The information was spatially distributed in 13 program areas and, at a smaller geographical scale, in 80 Primary Health Care Centers. CoproELISA surveys involved three randomized sampling periods (2003-05, 2009-10, 2017-18), with 1790 canine fecal samples. The US surveys were conducted in 2003-08, 2009-16 and 2017-18 in 34,515 children. Heat maps were created at the smallest geographic scale with QGIS 3.4.6. For the consecutive sampling periods, prevalence of positive canine fecal samples from livestock farms were 14.7, 12.1 and 7.8%, respectively, and children prevalence was 0.4, 0.2 and 0.1%, respectively. The study has been developed on a scale according to which the temporal-spatial distribution of CE allows to adjust control strategies in those areas of potential transmission of the zoonosis to humans.

El Síndrome Pulmonar por Hantavirus (SPH) es una enfermedad de etiología viral que causa en el hombre un cuadro respiratorio grave. En Patagonia, la enfermedad es causada por el virus Andes Sur (AND), transmitido por el roedor Oligoryzomys longicaudatus. El objetivo del presente trabajo fue identificar las actividades del hombre que favorecen su exposición a roedores, denominados escenarios de contagio. Se realizó un estudio retrospectivo a partir de información recolectada en investigaciones de casos ocurridos en Río Negro, mediante Fichas Clínico-Epidemiológicas e informes de evaluación ecológico/ambiental. Se definieron como variables a ser consideradas: edad, sexo, época del año, grado de urbanización, localización geográfica, integración del hombre al hábitat de roedores, fuente probable de exposición, actividad humana y nivel de saneamiento. Se estudiaron 32 casos. La exposición rural se verificó en 18 (56.2%) de los casos y 10 (31.3%) en paraje rural (grupo de viviendas en zona rural). En relación al ambiente antropogénico 24 (75%) resultaron en ambientes modificados por el hombre y 8 (25%) en áreas poco modificadas. El sitio de exposición de mayor importancia en El Bolsón fue el interior de edificaciones en 8 de los 18 casos allí registrados (44.5%), mientras que en Bariloche fueron ambientes de exterior con 8/14 (57.1%) casos. La actividad de riesgo fue laboral en 23 (71.9%) de los casos y recreacional en 7 (28.1%). Determinar los escenarios de contagio a nivel local ha aportado información para aplicar todos los recursos disponibles en materia de prevención y educación sanitaria.

“Black widow” spiders belong to the genus Latrodectus and are one of the few spiders in the world whose bite can cause severe envenomation in humans and domestic animals. In Argentina, these spiders are distributed throughout the country and are responsible for the highest number of bites by spiders of toxicological sanitary interest. Here, we studied the toxicity and some biochemical and immunochemical characteristics of eighteen venom samples from Latrodectus spiders from eight different provinces of Argentina, and the neutralization of some of these samples by two therapeutic antivenoms used in the country for the treatment of envenomation and by a anti-Latrodectus antivenom prepared against the venom of Latrodectus mactans from Mexico. We observed important toxicity in all the samples studied and a variation in the toxicity of samples, even in those from the same region and province and even in the same Latrodectus species from the same region. The therapeutic antivenoms efficiently neutralized all the venoms studied. Fil: de Roodt, Adolfo Rafael. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentina Fil: Lanari, Laura Cecilia. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: Laskowicz, Rodrigo Daniel. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: Costa de Oliveira, Vanessa. Universidad de Buenos Aires. Facultad de Medicina; Argentina Fil: Irazu, Lucia Elvira. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: Gonzalez, Alda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina Fil: Giambelluca, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina Fil: Nicolai, Néstor. Provincia de Buenos Aires. Ministerio de Salud. Dirección Laboratorio Central de Salud Pública; Argentina Fil: Barragán, Javier Hugo. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina Fil: Ramallo, Leticia. Provincia de Buenos Aires. Ministerio de Salud. Dirección Laboratorio Central de Salud Pública; Argentina Fil: López, Raúl Alfredo. Ministerio de Salud de la Provincia de Catamarca; Argentina Fil: Lopardo, Jorge. Secretaría Salud de la Provincia de Chubut; Argentina Fil: Jensen, Oscar. Secretaría Salud de la Provincia de Chubut; Argentina Fil: Larrieu, Edmundo Juan. Universidad Nacional de Río Negro; Argentina Fil: Calabró, Arnoldo. Ministerio de Salud de la Provincia de Rio Negro; Argentina Fil: Vurcharchuc, Miriam Guadalupe. Ministerio de Salud de la Provincia de Santiago del Estero; Argentina Fil: Lago, Néstor Rubén. Universidad de Buenos Aires. Facultad de Medicina; Argentina Fil: García, Susana Isabel. Ministerio de Salud de la Nación; Argentina Fil: de Titto, Ernesto Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Ministerio de Salud de la Nación; Argentina Fil: Damin, Carlos Fabian. Universidad de Buenos Aires. Facultad de Medicina; Argentina

Hydatidosis (cystic echinococcosis) is endemic in Rio Negro Province, Argentina. In 1980 started a control program against the disease. In 1984 Frider et al performed the first ultrasound screening in the world at Pilcaniyeu city, later extended to other localities of Rio Negro province. The initial prevalence in asymptomatic people was 7.1% in Pilcaniyeu and 10.1% in Comallo, being all new cases and with surgical indication.The aim of this investigation was to determine the current prevalence and analyze the evolution of the disease across 25 years of the control program.In 2009 and 2010 ultrasound screening studies were conducted in both locations in all age groups.In 512 ultrasound studies at Pilcaniyeu, the prevalence was 1.5% in children (6 to 14years old) and 4.2% in adults (total 2.5%). In 770 ultrasound studies at Comallo, the prevalence was 1.1 %in children and 6.6% in adults (total 3.0%). The overall reduction in the prevalence reached 67.2%. Regarding the age distribution, rates of 1.6%-1.9% were observed in Pilcaniyeu and of 1.0-1.9% in Comallo between 0 and 30 years old, increasing significantly above 10% after 60 years old in Pilcaniyeu and after 40 years old in Comallo.The implementation of the program actions reduced the prevalence of the disease but there are still new cases, and that indicates that some bias persists in the control of the epidemiology of the disease and levels of transmission to humans as a consequence of this failures. So the search of asymptomatic cases is still important and also their management based on the follow-up by ultrasound (watch and wait) or in the treatment with albendazol.

Hantavirus Pulmonary Syndrome (HPS) is a disease of viral etiology that affects humans causing severe acute respiratory symptoms. In Patagonia the disease is caused by the Andes Virus (AND) and transmitted by the rodent Oligoryzomys longicaudatus. The aim of this study was to identify those human activities that increase the risk of exposure to rodents, what we call "contagious scenarios". A retrospective study was performed with data obtained from cases in Rio Negro, which included clinic-epidemiological records and ecological/environmental assessment reports. The following variables were considered: age, sex, season, percentage of urbanization, geographic location, human settlements in rodent infested areas, probable source of exposure, type of activity and level of sanitary development. In total 32 cases were studied. Exposure was verified in 18 (56.2 %) cases in rural areas and 10 cases (31.3%) in small rural towns. In relation to anthropogenic environment, 24 (75%) cases were reported in developed settlements and 8 cases (25%) were related to slightly modified areas. Major exposition in El Bolson identified 8 cases of indoor activities of the total 18 reported in the area (44.5%), while in Bariloche 8 (57.1%) cases out of 14 were reported in outdoor surroundings. In general, activities that generated greater risk were work-related, accounting for 23 (71.9%) cases while 7 were related to recreational activities (28.1%). The identification of "contagious scenarios" at local level provided information for an effective application of available resources in terms of prevention and sanitary education.

Background Cystic echinococcosis (CE) is an important zoonotic disease caused by the cestode parasite Echinococcus granulosus. It occurs in many parts of the world where pastoral activities predominate, including the Rio Negro province of Argentina. Although CE control activities have been undertaken in the western regions of Rio Negro for more than two decades, the disease continues to remain prevalent in both the human and livestock animal populations. Vaccination of animal intermediate hosts of CE with the EG95 vaccine may provide a new opportunity to improve the effectiveness of CE control measures, although data are lacking about field application of the vaccine. Aims Evaluate the impact of EG95 vaccination in sheep on the transmission of Echinococcus granulosus in a field environment. Methodology Two trial sites were established in western Rio Negro province within indigenous communities. Vaccination of lambs born into one trial site was introduced and continued for 6 years. Prior to initiation of the trial, and at the end of the trial, the prevalence of CE in sheep was determined by necropsy. Weaned lambs received two injections of EG95 vaccine, approximately one month apart, and a single booster injection one year later. Vaccination was not implemented at the second trial site. A total of 2725 animals were vaccinated in the first year. Animals from this cohort as well as age-matched sheep from the control area were evaluated by necropsy. Key results Introduction of the vaccine led to a statistically significant in the number and size of hydatid cysts in comparison to the situation prior to the introduction of the vaccine, or compared to CE prevalence in the control area where the vaccine was not applied. The prevalence of infection in the vaccinated area was also significantly reduced by 62% compared to the re-intervention level, being lower than the prevalence seen in the control area, although the difference from the control area after the intervention was not significant possibly due to limitations in the numbers of animals available for necropsy. Conclusions Vaccination of sheep with the EG95 vaccine provides a valuable new tool which improves the effectiveness of CE control activities. Vaccination was effective even in a difficult, remote environment where only approximately half the lambs born into the communities were fully vaccinated., Author Summary Hydatid disease, otherwise known as cystic echinococcosis (CE), is caused by Echinococcus granulosus. The disease is common in many pastoral areas, including parts of the Rio Negro province of Argentina, and is formally recognised by the WHO as a Neglected Tropical Disease. We undertook the first scientific evaluation of the EG95 vaccine against transmission of hydatid disease in a field situation. Sheep in remote indigenous communities of Rio Negro were vaccinated over a six year period. Young lambs received two injections of vaccine and a single booster injection as one year old sheep. A similar region acted as a control where vaccination was not implemented. Evaluation of the outcomes of vaccination revealed a significant, 62% decrease in the prevalence of hydatid infection in 6 year old sheep. Our study provides a template for the application of vaccination in future efforts to control transmission of E. granulosus and reduce the burden of human disease caused by the parasite.