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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

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

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

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.

Cystic echinococcosis 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 is to assess the impact of the inclusion of the EG95 vaccine for sheep in the control programme, including analysis of the vaccine's operative feasibility in field conditions. The vaccine was applied in an area comprising four communities of native people including 79 farms with 3146 lambs and 311 dogs in total. Seventy one farms were designated as control areas where no vaccinations were undertaken while vaccinations of lambs undertaken on 91 farms. Lambs received two vaccinations with the EG95 vaccine followed by a single booster injection when the animals were 1-1.5 years of age. Farm locations were defined using GPS coordinates for the houses. Evidence for Echinococcus granulosus transmission was monitored by coproantigen ELISA on samples of dog faeces, by E. granulosus-specific PCR using soil samples, and anti-E. granulosus antibody assessments in sera from 2 to 4 teeth lambs, purgation of dogs to detect E. granulosus worms and necropsy on adult sheep. Before the vaccine was introduced, 26.2% of sheep with 2-4 teeth were positive using ELISA/WB, the prevalence decreased to 7.8% at the third year following use of the vaccine. Necropsy of animals older than 6 years (not vaccinated) showed that 66.1% of animals were infected with E. granulosus. In dogs, 4% was found positive for E. granulosus using arecoline purgation and 24.7% of the farms were infected using coproELISA/WB. During the first year of vaccination 2721 lambs received the first vaccine dose and 2448 received a booster. In the second year 2138 lambs were initially vaccinated and 1745 received a booster, and 1308 animals received the third dose. During the third year 1110 lambs received the first dose from which 539 received a booster and 723 animals received the third dose. An analysis of advantages and limitations of the diagnostic techniques used and the ability of the geospatial analysis to detect risk area are included. Based in the immunodiagnostic techniques, the EG95 vaccine has been able to prevent the infection in animals up to 3 years old. Also, the difficulties in the field for the correct vaccine administration and the social features and habits that may impact on echinococcosis control are included in the analysis.

Cystic echinococcosis (CE) is a chronic, complex and neglected disease caused by the larval stage of Echinococcus granulosus. The effects of this neglect have a stronger impact in remote rural areas whose inhabitants have no chances of being diagnosed and treated properly without leaving their jobs and travelling long distances, sometimes taking days to reach the closest referral center. Background In 1980 our group set up a control program in endemic regions with CE in rural sections of Rio Negro, Argentina. Since 1997, we have used abdominopelvic ultrasound (US) as a screening method of CE in school children and determined an algorithm of treatment. Objectives To describe the training system of general practitioners in early diagnosis and treatment of CE and to evaluate the impact of the implementation of the field program. Materials and Methods In 2000, to overcome the shortage of radiologists in the area, we set up a short training course on Focused Assessment with Sonography for Echinococcosis (FASE) for general practitioners with no previous experience with US. After the course, the trainees were able to carry out autonomous ultrasound surveys under the supervision of the course faculty. From 2000 to 2008, trainees carried out 22,793 ultrasound scans in children from 6 to 14 years of age, and diagnosed 87 (0.4%) new cases of CE. Forty-nine (56.4%) were treated with albendazole, 29 (33.3%) were monitored expectantly and 9 (10.3%) were treated with surgery. Discussion The introduction of a FASE course for general practitioners allowed for the screening of CE in a large population of individuals in remote endemic areas with persistent levels of transmission, thus overcoming the barrier of the great distance from tertiary care facilities. The ability of local practitioners to screen for CE using US saved the local residents costly travel time and missed work and proved to be an efficacious and least expensive intervention tool for both the community and health care system., Author Summary Cystic echinococcosis (CE) is an important and widespread disease that affects sheep, cattle, and humans living in areas where sheep and cattle are raised. CE is highly endemic in rural sections of Rio Negro, Argentina, where our group is based. However, it requires continuous monitoring of both populations with human disease best assessed by means of ultrasound (US) screening. This is challenging in remote rural areas due to the shortage of imaging specialists. To overcome this hurdle, we set up a two-day training program of Focused Assessment with Sonography for Echinococcosis (FASE) on CE for family medicine practitioners with no previous experience in US. After the course, they were equipped with portable US scanners and dispatched to remote rural areas in Rio Negro where they screened patients, located and staged the cysts and decided on the treatment with the help of surgeons and radiologists in local tertiary care centers. The need to travel to referral hospitals for traditional surgical interventions was therefore limited to a few cases. US was instead brought to rural areas thereby extending affordable healthcare to people who would otherwise not have access to it.

Cystic echinococcosis is an endemic disease in the Province of Rio Negro, Argentina. Ultrasound surveys carried out in 1984 found prevalence rates of 5.6% in children between 6 and 14 years of age. Objective To describe and to evaluate the results of the strategy applied in school children by hospital services of the Province of Rio Negro with regard to diagnosis, treatment and monitoring of cystic echinococcosis and to evaluate simultaneously the results of the control program against cystic echinococcosis. Materials and methods In 1997 ultrasound was chosen to carry out population surveys and the medical treatment criteria for the detected cases were standardized. The population under study involved 5745 students in the first survey and 22,793 in subsequent studies. The detected cases were classified according to Gharbi's scheme. A treatment algorithm was defined based only on monitoring (“watch and wait”), albendazole, surgery (open or laparoscopic) or mini-invasive procedures, according to type, location and size of the cyst. Information was also obtained on cases notified to the Health System between 1980 and 2008. Results In the first survey, 70 carriers (1.2%) were detected; of these, 25 started albendazole treatment (35.7%) and only 3 (4.3%) underwent surgery. Ten years after treatment, 60.1% of 42 cases, presented Types IV and V cysts and 14.5% presented total involution of their cysts. In subsequent studies, 87 (0.4%) cases were detected, 49 of which started albendazole treatment (56.3%) and 9 underwent surgery (10.3%). The incidence rate of cystic echinococcosis cases decreased from 38 × 100,000 in 1980 to 3.7 × 100,000 in 2008. Discussion A strong decrease in cystic echinococcosis was obtained although persistent levels of transmission were maintained. The cases produced under these conditions are diagnosed by means of ultrasound surveys and are treated using a plan based on albendazole and monitoring by the Health System during a period of 10 years.

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.