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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.

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.

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.