Design of a novel EmTSP-3 and EmTIP based multi-epitope vaccine against Echinococcus multilocularis infection.

Background: Current treatments and prevention strategies for echinococcosis are inadequate. Recent advancements in molecular vaccine development show promise against Echinococcus granulosus; however, Echinococcus multilocularis remains a challenge. A Multi-epitope Vaccine could potentially induce specific B and T lymphocyte responses, thereby offering protection against Echinococcus multilocularis infection. Methods: This study aimed to develop a MEV against alveolar echinococcosis. Key epitopes from the Echinococcus multilocularis proteins EmTSP3 and EmTIP were identified using immunoinformatics analyses. These analyses were conducted to assess the MEV feasibility, structural characteristics, molecular docking, molecular dynamics simulations, and immune simulations. The immunogenicity and antigenicity of the vaccine were evaluated through in vitro and in vivo experiments, employing ELISA, Western blotting, FCM, challenge infection experiments, and ELISPOT. Results: The effective antigenicity and immunogenicity of MEV were demonstrated through immunoinformatics, as well as in vitro and in vivo experiments. In vitro experiments revealed that MEV increased the secretion of IFN-γ and IL-4 in PBMC and successfully bound to specific antibodies in patient serum. Furthermore, mice immunized with MEV developed a robust immune response, characterized by elevated levels of CD4+ and CD8+ T-cells, increased secretion of IFN-γ and IL-4 by specific Th1 and Th2 cells, and heightened serum antibody levels. Importantly, MEV reduced the weight of cysts by conferring resistance against echinococcosis. These findings suggest that MEV is a promising candidate for the prevention of Echinococcus multilocularis infection. Conclusion: A total of 7 CTL, 7 HTL, 5 linear B-cell, and 2 conformational B-cell epitopes were identified. The vaccine has demonstrated effective antigenicity and immunogenicity against AE through molecular docking, immune simulation, molecular dynamics studies, and both in vitro and in vivo experiments. It provides effective protection against Echinococcus multilocularis infection, thereby laying a foundation for further development.

Optimizing sheep B-cell epitopes in Echinococcus granulosus recombinant antigen P29 for vaccine development.

Background: Echinococcus granulosus is a widespread zoonotic parasitic disease, significantly impacting human health and livestock development; however, no vaccine is currently available for humans. Our preliminary studies indicate that recombinant antigen P29 (rEg.P29) is a promising candidate for vaccine. Methods: Sheep were immunized with rEg.P29, and venous blood was collected at various time points. Serum was isolated, and the presence of specific antibodies was detected using ELISA. We designed and synthesized a total of 45 B cell monopeptides covering rEg.P29 using the overlap method. ELISA was employed to assess the serum antibodies of the immunized sheep for recognition of these overlapping peptides, leading to the preliminary identification of B cell epitopes. Utilizing these identified epitopes, new single peptides were designed, synthesized, and used to optimize and confirm B-cell epitopes. Results: rEg.P29 effectively induces a sustained antibody response in sheep, particularly characterized by high and stable levels of IgG. Eight B-cell epitopes of were identified, which were mainly distributed in three regions of rEg.P29. Finally, three B cell epitopes were identified and optimized: rEg.P2971-90, rEg.P29151-175, and rEg.P29211-235. These optimized epitopes were well recognized by antibodies in sheep and mice, and the efficacy of these three epitopes significantly increased when they were linked in tandem. Conclusion: Three B-cell epitopes were identified and optimized, and the efficacy of these epitopes was significantly enhanced by tandem connection, which indicated the feasibility of tandem peptide vaccine research. This laid a solid foundation for the development of epitope peptide vaccine for Echinococcus granulosus.

Cystic echinococcosis (Echinococcus granulosus sensu lato infection) in Tunisia, a One Health perspective for a future control programme.

The emergence of pandemics with dramatic consequences for human health has obscured endemic diseases that continue to pose a problem for human and animal health in several regions of the world. Among these diseases, cystic echinococcosis, a zoonotic parasitic infection caused by a group of cestodes, Echinococcus granulosus sensu lato, remains a real human and animal health problem in several regions of the world, including the Mediterranean Basin. Despite the implementation of a number of governmental control programmes using several tools (dog treatment, meat inspection, etc.), this infection is still highly prevalent in North Africa. Here we present a review of the epidemiology of cystic echinococcosis in Tunisia, an analysis of the constraints limiting the effectiveness of the control programmes implemented, and finally argue for the use of the One Health framework to improve the effectiveness of future programmes.

Immunization with a Mu-class glutathione transferase from Echinococcus granulosus induces efficient antibody responses and confers long-term protection against secondary cystic echinococcosis.

Cystic echinococcosis, a zoonosis caused by cestodes belonging to the Echinococcus granulosus sensu lato (s.l.) genetic complex, affects humans and diverse livestock species. Although a veterinary vaccine exhibiting high levels of antibody-mediated protection has successfully reached the market, the large genetic diversity among parasite isolates and their particular host preferences, makes still necessary the search for novel vaccine candidates. Glutathione transferases (GSTs) constitute attractive targets for immunoprophylaxis due to their outstanding relevance in helminth detoxification processes, against both exogenous and endogenous stressors. Among the six GSTs known to be expressed in E. granulosus s.l., EgGST1 (Mu-class), EgGST2 (Sigma-class), and EgGST3 (a still non-classifiable isoenzyme), show the highest proteomic expression. Therefore, their recombinant forms -rEgGST1, rEgGST2 and rEgGST3- were herein analyzed regarding their potential to induce long-term antiparasite protection in mice. Only immunization with rEgGST1 induced long-lasting protection; and accordingly, rEgGST1-specific antibodies enhanced the parasite killing through both the classical activation of the host complement system and the antibody-dependent cellular cytotoxicity by macrophages. These results support further testing of rEgGST1 as a vaccine candidate in diverse hosts due to the broad expression of EgGST1 in different parasite stages and tissues.

Epidemiological update of cystic echinococcosis in livestock and assessment of practices related to its control in the Mediterranean area.

Cystic echinococcosis (CE), caused by the tapeworm Echinococcus granulosus, is a zoonotic parasitic disease that still represents a serious threat to human and animal health worldwide. The Mediterranean basin is recognized as one of the major hotspots of CE due to several factors, including the presence of diverse intermediate host species as well as socio-economic and cultural conditions of local communities. This study aims to take a closer look at epidemiological data on CE in the Mediterranean area and assess the knowledge attitudes and practices of shepherds towards this disease in four countries (Algeria, Greece, Italy and Tunisia), highly endemic for CE, with the final goal of identifying highly endemic risk areas and practices in use which might potentially allow the persistence of E. granulosus infection in these areas. To update the epidemiological scenario of CE in Mediterranean areas, a comprehensive review of peer-reviewed literature on CE prevalence data published during the 2017-2023 period was carried out and, through a geographical information system (GIS), a map displaying the current CE distribution in the Mediterranean area was generated. In addition, a questionnaire survey was conducted through in-depth interviews of the farmers to collect information on their management system as well as knowledge attitudes and practices towards CE. From the farmer-participatory survey some risky practices emerged including the non-regular deworming of dogs or the use of ineffective drugs or dosing, as well as the provision of uncooked animal viscera to dogs. Finally, lower levels of knowledge and awareness of the disease was observed among farmers from North Africa compared with those of European countries. In conclusion, the results obtained highlight that CE is still a very serious problem in Mediterranean areas and increased efforts are needed to promote awareness among farmers and to turn research results into policy in order to reduce the spread of this disease, according to the One Health perspective.

Baiting not-owned dogs against Echinococcus granulosus: innovative tools for integrated control.

Cystic echinococcosis (CE), caused by the larval stage of the cestode Echinococcus granulosus, is one of the most widespread zoonoses in Mediterranean countries. Baiting not-owned dogs with praziquantel (PZQ), due to their key role in the maintaining the transmission of CE, currently appears to be the most effective way to limit the transmission of CE, as well as an important aspect to introduce for the control of this parasitic disease. Therefore, this study aims to test 3 types of PZQ-based baits by evaluating different parameters (integrity over time, attractiveness and palatability for dogs, and mechanical resistance after release to different altitudes) and the bait acceptance in field by target animals, i.e. not-owned dogs, by using camera traps. The double PZQ-laced baits (with a double layer of highly palatable chews) showed the greatest resistance in the environment while also preserving the attractiveness and palatability up to 10 days, also withstood heights of 25 m, thus resulting as the most suitable also for drone delivery. The results on the field showed that most of the baits were consumed by not-owned dogs (82.2%), while the remaining were consumed by wild boars (8.9%), foxes (6.7%), badgers (1.1%) and hedgehogs (1.1%), confirming the specific and high attractiveness of the double PZQ-laced baits for the target population and highlights how an anthelmintic baiting programme may be a viable tool for the management of E. granulosus among free-ranging dog populations in endemic rural areas.

[Surveillance of echinococcosis in Bayingolin Mongol Autonomous Prefecture, Xinjiang Uygur Autonomous Region from 2017 to 2022].

OBJECTIVE: To analyze the echinococcosis surveillance results in Bayingolin Mongol Autonomous Prefecture, Xinjiang Uygur Autonomous Region from 2017 to 2022, so as to provide insights into formulation of echinococcosis control measures in the prefecture. METHODS: Villagers were randomly sampled using a multistage sampling method from class I and II echinococcosis endemic counties in Bayingolin Mongolian Autonomous Prefecture from 2017 to 2022 for detection of human echinococcosis, while all patients undergoing ultrasound examinations in medical institutions in class III endemic counties received active echinococcosis screening. In addition, livestock in centralized slaughterhouses or slaughtering sites were screened for echinococcosis using the palpation and necropsy method, and fresh domestic dog feces samples were collected from randomly selected dog owners in each administrative village for detection of Echinococcus copro-antigen in domestic dogs. The trends in detection of human and livestock echinococcosis, detection of newly diagnosed human echinococcosis cases and detection of Echinococcus coproantigen in domestic dogs were analyzed in Bayingolin Mongol Autonomous Prefecture from 2017 to 2022. RESULTS: The mean detection rate of human echinococcosis was 0.13% (540/407 803) in Bayingolin Mongol Autonomous Prefecture from 2017 to 2022, which appeared a tendency towards a decline over years (χ2trend = 1 217.21, P < 0.001), and the highest detection of newly diagnosed echinococcosis cases was seen in Hejing County (0.28%, 191/67 865). The detection of livestock echinococcosis appeared a tendency towards a decline over years from 2017 to 2022 (χ2trend = 147.02, P < 0.001), with the highest detection rate seen in Hejing County (3.44%, 86/2 500), and the detection of Echinococcus copro-antigen in domestic dogs appeared a tendency towards a decline over years from 2017 to 2022 (χ2trend = 302.46, P < 0.001), with the highest detection rate in Qiemo County (2.74%, 118/4 313). CONCLUSIONS: The detection of human and livestock echinococcosis and dog feces antigens Echinococcus copro-antigen in domestic dogs all appeared a tendency towards a decline in Bayingolin Mongol Autonomous Prefecture, Xinjiang Uygur Autonomous Region from 2017 to 2022; however, there is still a high echinococcosis transmission risk in local areas. Sustainable integrated echinococcosis control is required in Bayingolin Mongol Autonomous Prefecture.

[Effectiveness of comprehensive echinococcosis control measures with emphasis on management of infectious source in Sichuan Province from 2010 to 2022].

OBJECTIVE: To evaluate the effectiveness of comprehensive echinococcosis control measures with emphasis on management of infectious source in Sichuan Province from 2010 to 2022, so as to provide insights into formulation of future control interventions. METHODS: Data pertaining to comprehensive echinococcosis control measures with emphasis on management of infectious source and echinococcosis surveillance in Sichuan Province from 2010 to 2022 were collected. The effectiveness of comprehensive echinococcosis control measures with emphasis on management of infectious source was evaluated with prevalence of human echinococcosis, detection of newly diagnosed echinococcosis patients, prevalence of Echinococcus infection in domestic dogs, prevalence of cystic echinococcosis in livestock, prevalence of alveolar echinococcosis in small mammals and awareness of echinococcosis control knowledge, and Spearman's rank correlation analysis. RESULTS: The prevalence of human echinococcosis reduced from 1.08% in 2010 to 0.40% in 2022 in Sichuan Province (χ2 = 1 482.97, P < 0.05), with a reduction from 0.30% to 0.02% in the detection of newly diagnosed echinococcosis cases (χ2 = 2 776.41, P < 0.05), a reduction from 15.87% to 0.46% in the prevalence of Echinococcus infection in domestic dogs (χ2 = 20 823.96, P < 0.05), a reduction from 8.05% to 1.07% in the prevalence of cystic echinococcosis in livestock (χ2 = 1 296.02, P < 0.05), and the awareness of echinococcosis control knowledge increased from 50.65% to 95.24% (χ2 = 34 938.63, P < 0.05); in addition, there was a year-specific prevalence rate of alveolar echinococcosis in small mammals (χ2 = 164.07, P < 0.05). Spearman's rank correlation analysis revealed that the detection of newly diagnosed echinococcosis cases correlated positively with the prevalence of Echinococcus infections in domestic dogs (rs = 0.823, P < 0.05) and the prevalence of cystic echinococcosis in livestock (rs = 0.795, P < 0.05), and correlated negatively with the awareness of echinococcosis control knowledge (rs = - 0.918, P < 0.05), and the prevalence of Echinococcus infection in domestic dogs correlated positively with the prevalence of cystic echinococcosis in livestock (rs = 0.753, P < 0.05) and negatively with the awareness of echinococcosis control knowledge (rs = -0.747, P < 0.05); however, there was no correlation between the prevalence of Echinococcus infections in domestic dogs and the prevalence of alveolar echinococcosis in small mammals (rs = -0.750, P > 0.05). CONCLUSIONS: The comprehensive echinococcosis control measures with emphasis on management of infectious source had achieved remarkable effectiveness in Sichuan Province; however, the transmission chain of echinococcosis has not been interrupted. Reinforced comprehensive echinococcosis control measures with emphasis on management of infectious source and sustained tracking evaluation of the effectiveness are recommended in Sichuan Province.

[Effectiveness of the central government-funded echinococcosis control programme in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022].

OBJECTIVE: To evaluate the effectiveness of the central government-funded echinococcosis control programme in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, so as to provide insights into echinococcosis control. METHODS: Administrative villages were sampled using a multi-stage cluster random sampling method from Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, and all residents at ages of 12 years and older in the sampled villages were screened for echinococcosis, and schools were sampled using a cluster sampling method, and all children at ages of 12 years and older in the sampled schools were screened for echinococcosis. Domestic dogs were sampled using a systematic random sampling method, and one domestic dog stool sample was collected from each household. Stray dog stool samples were collected outside the villages, and Echinococcus coproantigens were detected using enzyme-linked immunosorbent assay in domestic and stray dogs. In addition, echinococcosis was screened in sheep and cattle in designated slaughterhouses in Tianzhu Tibetan Autonomous County. The trends in the prevalence of echinococcosis in humans and livestock and the positive rate of Echinococcus coproantigens in dogs were examined with the Cochran-Armitage trend test. In addition, individuals screened for echinococcosis were randomly sampled from 2007 to 2022 for survey on the awareness of echinococcosis control knowledge. RESULTS: A total of 290 356 person-times were screened for echinococcosis among residents at ages of 12 years and older in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, with 1 094 residents detected with cystic echinococcosis, and the detection of echinococcosis appeared a tendency towards a gradual decline over years (χ2 = 358.602, P < 0.001). A total of 32 931 person-times were screened for echinococcosis among children at ages of 12 years and older in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, with 296 children detected with echinococcosis, and the detection of echinococcosis appeared a tendency towards a gradual decline over years (χ2 = 267.673, P < 0.001). A total of 33 230 domestic dog stool samples were tested for Echinococcus coproantigens in Tianzhu Tibetan Autonomous County, Gansu Province from 2007 to 2022, with 1 777 Echinococcus coproantigens-positive samples tested, and the positive rate of Echinococcus coproantigens appeared a tendency towards a decline in domestic dogs over years (χ2 = 2 210.428, P < 0.001), while the positive rate of Echinococcus coproantigens showed a tendency towards a rise in domestic animals from 2016 to 2022 (χ2 = 37.745, P < 0.001). The positive rate of Echinococcus coproantigens remained relatively stable in stray dogs in Tianzhu Tibetan Autonomous County, Gansu Province from 2019 to 2022 (χ2 = 0.315, P = 0.575). A total of 10 973 sheep were screened for echinococcosis in Tianzhu Tibetan Autonomous County from 2007 to 2022, with 334 sheep detected with echinococcosis, and the detection of echinococcosis appeared a tendency towards a decline in sheep over years (χ2 = 53.579, P < 0.001); however, there was no significant change in the detection of echinococcosis during the period from 2015 through 2022 (χ2 = 1.520, P = 0.218). A total of 2 400 cattle were screened for echinococcosis in Tianzhu Tibetan Autonomous County from 2017 to 2022, with 231 cattle detected with echinococcosis, and the detection of echinococcosis showed a tendency towards a decline over years (χ2 = 5.579, P < 0.05). The awareness of echinococcosis control knowledge increased from 44.37% in 2007 to 94.00% in 2022 among residents at ages of 12 years and older and from 52.50% in 2007 to 92.50% in 2022 among children at ages of 12 years and older in Tianzhu Tibetan Autonomous County, respectively. CONCLUSIONS: There has been a reduction in the detection of echinococcosis in humans and domestic animals and the positive rate of Echinococcus coproantigens in dogs and a rise in the awareness of the echinococcosis control knowledge following the implementation of the central government-funded echinococcosis control programme in Tianzhu Tibetan Autonomous County, Gansu Province; however, integrated echinococcosis control measures are still required for further control of the prevalence of echinococcosis.

An innovative strategy for deworming dogs in Mediterranean areas highly endemic for cystic echinococcosis.

BACKGROUND: Cystic echinococcosis (CE), caused by the larval stage of Echinococcus granulosus sensu lato, is a zoonotic parasitic disease of economic and public health importance worldwide, especially in the Mediterranean area. Canids are the main definitive hosts of the adult cestode contaminating the environment with parasite eggs released with feces. In rural and peri-urban areas, the risk of transmission to livestock as well as humans is high because of the free-roaming behavior of owned/not owned dogs. Collecting data on animal movements and behavior using GPS dataloggers could be a milestone to contain the spread of this parasitosis. Thus, this study aims to develop a comprehensive control strategy, focused on deworming a dog population in a pilot area of southern Italy (Campania region) highly endemic for CE. METHODS: Accordingly, five sheep farms, tested to be positive for CE, were selected. In each sheep farm, all shepherd dogs present were treated every 2 months with praziquantel. Furthermore, 15 GPS dataloggers were applied to sheep and dogs, and their movements were tracked for 1 month; the distances that they traveled and their respective home ranges were determined using minimum convex polygon (MCP) analysis with a convex hull geometry as output. RESULTS: The results showed that the mean daily walking distances traveled by sheep and dogs did not significantly differ. Over 90% of the point locations collected by GPS fell within 1500 mt of the farm, and the longest distances were traveled between 10:00 and 17:00. In all the sheep farms monitored, the area traversed by the animals during their daily activities showed an extension of < 250 hectares. Based on the home range of the animals, the area with the highest risk of access from canids (minimum safe convex polygon) was estimated around the centroid of each farm, and a potential scheme for the delivery of praziquantel-laced baits for the treatment of not owned dogs gravitating around the grazing area was designed. CONCLUSIONS: This study documents the usefulness of geospatial technology in supporting parasite control strategies to reduce disease transmission.

China's prevention and control experience of echinococcosis: A 19-year retrospective.

Echinococcosis poses a significant threat to public health. The Chinese government has implemented prevention and control measures to mitigate the impact of the disease. By analyzing data from the Chinese Center for Disease Control and Prevention and the State Council of the People's Republic of China, we found that implementation of these measures has reduced the infection rate by nearly 50% between 2004 to 2022 (from 0.3975 to 0.1944 per 100,000 person-years). Nonetheless, some regions still bear a significant disease burden, and lack of detailed information limites further evaluation of the effects on both alveolar and cystic echinococcosis. Our analysis supports the continuing implementation of these measures and suggests that enhanced wildlife management, case-based strategies, and surveillance systems will facilitate disease control.

Knowledge, awareness and practice regarding cystic echinococcosis in Algeria: A cross-sectional survey among the general population.

Cystic echinococcosis (CE) is a parasitic zoonotic disease with a widespread occurrence, particularly in developing countries. Known as a neglected disease, it is highly prevalent in Algeria with a significant public health concern and substantial financial losses. The objectives of this study was to explore knowledge and awareness and practice of the Algerian population regarding this disease. A cross-sectional online-based survey was conducted between July 15 and September 25, 2022 using a self-administered questionnaire targeting all Algerian people of more than 18 years of age. Out of the total respondents, 87.7% have ever heard of CE with livestock rearing connection (OR:2.550, CI 95% OR: 1.108-5.870) and educational level (OR:3.826, CI 95% OR: 1.599-9.156) as the main factors associated with the level of awareness. Regarding their knowledge, results showed dispersing notions about the disease. The majority (84.8%) were aware of the zonnotic nature of the disease while only 49.6% knew that CE is caused by parasitic disease. Also, 83.3% were knowledgeable of the role of contaminated offal in the contamination of dogs which are considered as the main source of contamination of humans (65.19%). Regarding their practices, even home slaughtering was common (92.96%), some positive attitudes were prevalent where most of the participants declared washing vegetable before consumption (97.41%) and washing their hands after touching a dog (91.11%). Also, 68.29% among the dog owners declared that deworming their pets. This study has revealed that despite the high level of awareness and some positive attitudes, the level of knowledge about CE among the Algerian public has shown some gaps related to the epidemiology of the disease. These results could be helpful for the awareness campaigns programmers in their missions through focusing their efforts on raising the level of knowledge for the items that have shown a lack of understand which will be of great importance in the strategy of CE elimination.

Immunoprotective effect and mechanism of rEg.P29 against CD4 + T cell-deficient mice with Echinococcus multilocularis infection.

Alveolar echinococcosis (AE) is a zoonotic parasitic disease caused by infection with the larval stage of Echinococcus multilocularis and a major challenge to human public health. Vaccines are the most effective way to prevent and control infectious diseases. We previously revealed that the Echinocuccus granulosus recombinant protein P29 is a good vaccine candidate against E. granulosus. However, the protective and immunological mechanism of rEg.P29 against E. multilocularis remain unclear. In this study, CD4 + T cell-deficient mice are transferred with spleen CD4 + T cells isolated from wild-type mice and subjected to rEg.P29 immunization, and then these immunized mice are infected with E. multilocularis. The cyst inhibition rate is calculated by weighing the body and cyst weights. The level of antibody is detected by ELISA. Flow cytometry is used to detect the level of IFN-γ production by CD4 + T and CD8 + T cells. The cytokines in culture supernatant are detected by ELISA. The expressions of CD44 and CD62L on memory T cells are determined by flow cytometry. The results show the cyst inhibition rate is 41.52% after adoptive transfer of CD4 + T cells. Furthermore, the levels of IgG, IgM, IgA and IgE in serum are significantly increased compared with those in the PBS group. The IFN-γ-secretion by CD8 + T cells and the level of IFN-γ in culture supernatant are obviously increased; and the number of CD4 + T cells is increased, but the number of IFN-γ producing CD4 + T cells has no significant difference compared with PBS group. In addition, the number of CD44 +CD62L ‒CD8 + memory T cells in the spleen is significantly increased, while the number of CD44 ‒CD62L + CD8 + memory T cells is not significantly altered. Collectively, rEg.P29 can alleviate E. multilocularis infection by inducing humoral immune responses and CD8 + T cell responses.

Protective efficacy of six recombinant proteins as vaccine candidates against Echinococcus granulosus in dogs.

BACKGROUND: Cystic echinococcosis (CE) is caused by the infection of Echinococcus granulosus sensu lato (E. granulosus s.l.), one of the most harmful zoonotic helminths worldwide. Infected dogs are the major source of CE transmission. While praziquantel-based deworming is a main measure employed to control dog infections, its efficacy is at times compromised by the persistent high rate of dog re-infection and the copious discharge of E. granulosus eggs into the environment. Therefore, the dog vaccine is a welcome development, as it offers a substantial reduction in the biomass of E. granulosus. This study aimed to use previous insights into E. granulosus functional genes to further assess the protective efficacy of six recombinant proteins in dogs using a two-time injection vaccination strategy. METHODS: We expressed and combined recombinant E. granulosus triosephosphate isomerase (rEgTIM) with annexin B3 (rEgANXB3), adenylate kinase 1 (rEgADK1) with Echinococcus protoscolex calcium binding protein 1 (rEgEPC1), and fatty acid-binding protein (rEgFABP) with paramyosin (rEgA31). Beagle dogs received two subcutaneous vaccinations mixed with Quil-A adjuvant, and subsequently orally challenged with protoscoleces two weeks after booster vaccination. All dogs were sacrificed for counting and measuring E. granulosus tapeworms at 28 days post-infection, and the level of serum IgG was detected by ELISA. RESULTS: Dogs vaccinated with rEgTIM&rEgANXB3, rEgADK1&rEgEPC1, and rEgFABP-EgA31 protein groups exhibited significant protectiveness, with a worm reduction rate of 71%, 57%, and 67%, respectively, compared to the control group (P < 0.05). Additionally, the vaccinated groups exhibited an inhibition of worm growth, as evidenced by a reduction in body length and width (P < 0.05). Furthermore, the level of IgG in the vaccinated dogs was significantly higher than that of the control dogs (P < 0.05). CONCLUSION: These verified candidates may be promising vaccines for the prevention of E. granulosus infection in dogs following two injections. The rEgTIM&rEgANXB3 co-administrated vaccine underscored the potential for the highest protective efficacy and superior protection stability for controlling E. granulosus infections in dogs.

Intervención educativa en una enfermedad desatendida: hidatidosis/ equinococosis quística en escolares del norte de Chile / Educational intervention in a neglected disease: hydatidosis/cystic echinococcosis in schoolchildren in northern Chile

INTRODUCCIÓN: La hidatidosis es una zoonosis cuyo control más eficiente y eficaz es la promoción en salud, especialmente en la población infante-juvenil. OBJETIVO: Medir el impacto de un programa de intervención educativa sobre hidatidosis en escolares del norte de Chile. MÉTODO: Estudio intervencional educativo con fases pre y post test en 3.145 estudiantes de educación preescolar, primaria y secundaria de tres comunas. Se definieron dimensiones, unidades educativas y sistemas de evaluación incorporados en las bases curriculares. Se calculó el puntaje de logro de respuestas correctas utilizando la prueba t. Se estimó el tamaño del efecto mediante d de Cohen y análisis de varianza mixto. RESULTADOS: Se encontraron diferencias estadísticamente significativas en la muestra total y en las variables género, comuna, procedencia rural-urbana y nivel de educación. Los puntajes post intervención fueron mayores y con tamaños de efecto grandes a excepción de los primeros niveles de educación. Se hallaron puntajes mayores post test y efectos de interacción con diferencias significativas en rural-urbano y en comuna anteriormente intervenida. La dimensión mejor evaluada fue "medidas de autocuidado" y la más baja "tenencia responsable de perros". CONCLUSIONES: El programa educativo fue efectivo al ser dirigido a grupos etarios, mediante métodos pedagógicos en las bases curriculares de los establecimientos educacionales.

BACKGROUND: Hydatidosis is a zoonosis whose most efficient and effective control is health promotion, especially in children and youth. AIM: To measure the impact of an educational intervention program on hydatidosis in schoolchildren in northern Chile. METHOD: Educational interventional study was performed with pre-post test phases in 3,145 students of preschool, primary and secondary education from three districts. Dimensions, educational units and evaluation systems were defined and incorporated into the curricular bases. The correct answer achievement score was calculated using the T-test. Effect size was estimated using Cohen's d and mixed analysis of variance. RESULTS: Statistically significant differences were found in the total sample and in variables such as gender, district, rural-urban origin and level of education. Post-intervention scores were higher than pre-intervention and with large effect sizes, except for the first levels of education. Higher post-test scores and interaction effects were found with significant differences in rural-urban and in a previously intervened district. The best evaluated dimension was "self-care measures" and the lowest was "responsibly keeping dogs". CONCLUSIONS: The educational program was effective when directed to age groups, through pedagogical methods in the curricular bases of educational facilities.

Development of an oral nanovaccine for dogs against Echinococcus granulosus.

Dogs are the main source of animal and human cystic echinococcosis caused by the Cestode parasite Echinococcus granulosus. Dog vaccination seems to be a good strategy to control this parasitic disease. Here we present the development of a polymeric nanoparticle-based oral vaccine for dogs against Echinococcus granulosus delivered in enteric-coated capsules. To achieve our target, we encapsulated two recombinant antigens into biodegradable polymeric nanoparticles in the presence of Monophosphoryl lipid A as an adjuvant to ensure efficient delivery and activation of a protective mucosal immune response. The formulated delivery system showed a nanoparticle size less than 200 nm with more than 80 % antigen encapsulation efficiency and conserved integrity and immunogenicity. The nanoparticle surface was coated with chitosan to enhance adhesion to the gut mucosa and a subsequent antigen delivery. Chitosan-coated nanoparticles showed a higher cell internalization in murine macrophages and dendritic cells as well as a higher penetration into Caco-2 cells in vitro. Antigen-loaded nanoparticles were freeze-dried and enteric-coated capsules were filled with the obtained powder. The obtained results show a promising nanoparticles delivery system for oral vaccination.

Estrategias de control de la Equinococosis quística en el Uruguay / Strategies for the control of cystic echinococcosis in Uruguay / Estratégias de controle da equinococose cística no Uruguai

La equinococosis quística es una zoonosis de origen parasitario con distribución cosmopolita. En nuestro país continúa siendo una enfermedad endémica, afectando principalmente pequeños centros poblados y áreas rurales pobres relacionadas a la producción ovina. Los planes de control requieren de un abordaje holístico, con la participación de diferentes instituciones, profesionales y en especial de la comunidad. La cooperación regional busca monitorizar el avance de la enfermedad y centrar las medidas de acción sobre cuatro ejes, definidos según los puntos de intervención más comunes para la quiebra del ciclo de transmisión y la consecuente reducción en incidencia y prevalencia de la enfermedad. La presente revisión utilizó literatura obtenida en diferentes bases de datos, bibliotecas virtuales y sitios web regionales y locales con el objetivo describir las principales estrategias de control, vigilancia y prevención aplicadas actualmente en nuestro país.

Cystic echinococcosis is a zoonosis of parasitic origin with cosmopolitan distribution. In our country it continues to be an endemic disease, affecting mainly small population centers and poor rural areas related to sheep production. Control plans require a holistic approach, with the participation of different institutions, professionals and especially the community. Regional cooperation seeks to monitor the progress of the disease and focus action measures on four axes, defined according to the most common points of intervention to break the transmission cycle and consequently reduce the incidence and prevalence of the disease. This review used literature obtained from different databases, virtual libraries and regional and local websites with the aim of describing the main control, surveillance and prevention strategies currently applied in our country.

A equinococose cística é uma zoonose de origem parasitária com distribuição cosmopolita. Em nosso país, continua a ser uma doença endêmica, afetando principalmente pequenos centros populacionais e áreas rurais pobres relacionadas à produção de ovinos. Os planos de controle exigem uma abordagem holística, com a participação de diferentes instituições, profissionais e, principalmente, da comunidade. A cooperação regional busca monitorar o progresso da doença e concentrar as medidas de ação em quatro eixos, definidos de acordo com os pontos de intervenção mais comuns para interromper o ciclo de transmissão e, consequentemente, reduzir a incidência e a prevalência da doença. Esta revisão utilizou a literatura obtida em diferentes bases de dados, bibliotecas virtuais e sites regionais e locais com o objetivo de descrever as principais estratégias de controle, vigilância e prevenção aplicadas atualmente em nosso país.

A DNA vaccine (EG95-PT1/2/3-IL2) encoding multi-epitope antigen and IL-2 provokes efficient and long-term immunity to echinococcosis.

Echinococcosis is a highly prevalent global zoonosis, and vaccines are required. The commercial vaccine based on a protein-based subunit (EG95), however, is limited by its insufficient cellular immunity, a short protection period, and limited prevention against novel mutant strains. Herein, we applied bioinformatics to develop a DNA vaccine (pEG95-IL2) expressing both multi-epitope-based antigens (EG95-PT1/2/3) and an IL-2 adjuvant to regulate T cell differentiation and memory cell response. EG95-PT1/2/3 was screened with hierarchical structure prediction from the epitope conformation of B cells with high confidence across various species to guarantee immunogenicity. Importantly, cationic arginine-rich lipid nanoparticles (RNP) were utilized as a delivery vehicle to form lipoplexes that had a transfection efficiency of nearly two orders of magnitude greater than that of commercial reagents (Lipofectamine 2000 and polyethyleneimine) with both immune and nonimmune cells (DC2.4 and L929 cells, respectively). RNP/pEG95-IL2 lipoplexes displayed a robust and long-term antigen expression, as well as adjuvant effects during the immunization. Consequently, intramuscular injection of RNP/pEG95-IL2 elicited similar humoral immune responses and significantly greater cellular responses in mice when compared with those of the commercial vaccine. In addition, the inoculation protocol of RNP/pEG95-IL2 with sequential booster further strengthens cellular immunity in comparison with the homologous booster. Those findings provide a promising strategy for improving plasmid vaccine efficacy.

In silico Analysis of a 29 kDa Echinococcus granulosus Protoscolex Protein (P29) as a Vaccine Candidate against Cystic Echinococcosis.

Vaccination can be a key step in controlling hydatid cyst infection in humans and livestock in endemic areas of the disease. The aim of the Present study was to determine some of the basal biochemical properties followed by prediction and screening of B-cell and MHC-binding epitopes of EgP29 protein in silico. Some of the basic physico-chemical properties along with antigenicity, allergenicity, solubility, post-translational modification (PTM) sites, subcellular localization, signal peptide, transmembrane domain, secondary and tertiary structures followed by refinement and validations were computationally determined for this protein. Also, B-cell epitopes were predicted and screened using various web servers, while MHC-binding and CTL epitopes were predicted using IEDB and NetCTL servers, respectively. The protein is a 238-residue, 27 kDa molecule, with high thermotolerance (aliphatic: 71.81) and hydrophilicity (negative GRAVY). There were several glycosylation and phosphorylation sites in the sequence, without a transmembrane domain and signal peptide. Moreover, several B-cell and MHC-binding epitopes were found in the EgP29 protein, which could be further used in multi-epitope vaccines. In conclusion, results of the present study can be a promising sign for achieving effective approaches to the preparation of a multi-epitope vaccines against echinococcosis. So, it is necessary that the effectiveness of the protein and its epitopes be evaluated in vitro and in vivo.

Current status of cystic echinococcosis control in the Falkland Islands: has elimination been achieved?

Attempts to control cystic echinococcosis (CE) caused by Echinococcus granulosus in the Falkland Islands have been ongoing for over 50 years. No human cases have been recorded since the 1980s but there is a need to establish if the parasite has been completely eliminated from domestic animals. A study was carried out in 2018/2019 to identify dogs infected with E. granulosus using copro-antigen and copro-polymerase chain reaction (PCR) analysis. In addition, annual slaughter data were analysed to establish infection levels of E. granulosus and 2 other taeniid parasites. Results showed that 4 out of 589 dogs (0.7%) tested positive by copro-antigen analysis. Results from similar surveys carried out in 2010, 2012 and 2014 showed 17 (3%), 0 and 6 (1%) copro-antigen-positive dogs, respectively, with 8 dogs being confirmed by PCR in 2010. Annual abattoir data showed that from 2006 to 2020, 36 sheep were identified with E. granulosus (mean 0.0055%), 14 186 sheep with Taenia hydatigena (mean 2.2%) and 465 with Taenia ovis (mean 0.072%). Prevalences of T. hydatigena and T. ovis showed spontaneous rises in certain years where the infections could also be detected in lambs indicating that viable taeniid eggs were present. Observations of farm management procedures indicated that there were occasions when dogs could get access to infective taeniid material. In conclusion, E. granulosus is still present in sheep and dogs but at low prevalences. The increasing presence of T. hydatigena however, indicates that control measures are defective in some areas and there is potential for a re-emergence of CE.