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.

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.

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.

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.

Echinococcoses in Iran, Turkey, and Pakistan: Old Diseases in the New Millennium.

Echinococcosis is considered a cosmopolitan zoonosis caused by different species of small taeniid tapeworms of the genus Echinococcus and is regarded as a neglected zoonosis. Cystic and alveolar echinococcoses are endemic diseases of Tibetan, Pamir, and Iranian plateaus. All of the countries within the Iranian plateau are affected by echinococcosis. Pakistan, Turkey, and Iran are the three most populous countries of the region, in which echinococcosis is highly endemic. The three neighboring countries share strong cultural and socioeconomic ties. The present study aimed to provide a broad review of the status of cystic and alveolar echinococcosis, summarizing the current knowledge about geographical distribution, molecular epidemiology, and transmission dynamics of Echinococcus granulosus sensu lato and Echinococcus multilocularis in this region. Additionally, we aimed to understand disease burden and risk factors as basic requirements for establishing a surveillance system and planning prevention and control programs. A considerable body of information is available on different aspects of echinococcosis in this region; however, several information and research gaps need to be filled before planning control programs. None of the countries in the region have an elaborate echinococcosis control program. Effective control programs require multi/intersectoral coordination within a One Health approach with a long-term political and administrative commitment and enhanced international collaboration among the three countries.

Treatment of protoscoleces with gamma radiation: Potential immunoprotective effect against experimental murine echinococcosis.

Cystic echinococcosis (CE) is one of the most important zoonotic diseases with a worldwide distribution. It is caused by the larval stage of the dog tapeworm "Echinococcus granulosussensu lato" and constitutes a major economic and public health problem in several countries. Protoscoleces are one component of this larval stage that can interact with both definitive and intermediate hosts. The aim of the present study was to investigate the potential role of using a radio-attenuated form of these protoscoleces for immunoprophylaxis against experimental murine echinococcosis. However, mice were immunized twice at 15-day intervals with gamma (γ) irradiated protoscoleces at doses of 0.4, 0.8, 1.2 and 1.4 kGy then challenged with the intact parasites. Macroscopic and histological analyses with cytokine measurements were performed in order to estimate the number and diameter of cysts, microscopic changes and cytokine profile. An improvement in protection against the challenge dose was observed with increasing dose, giving percentages of 47.7, 49, 55.23 and 70.6%, for the 0.4, 0.8, 1.2 and 1.4 kGy-groups respectively. These data suggest that immunization with radio-attenuated protoscoleces may induce satisfactory protective immunity by reducing successfully the formation of cysts, caused by challenge infection.

Association between echinococcosis-specific health literacy and behavioural intention to prevent echinococcosis among herdsmen on the Tibet Plateau in China: a cross-sectional study.

BACKGROUND: Echinococcosis is considered a neglected zoonotic disease and has been a major worldwide public health problem. Although it is known that health literacy is closely related to health behaviours and health outcomes, few studies have paid attention to echinococcosis related health literacy. This study aims to examine the association between echinococcosis-specific health literacy (ES-HL) and behavioural intention to prevent echinococcosis (BIPE) among herdsmen on the Tibet Plateauin in China. METHODS: A cross-sectional study of 401 Tibetan herdsmen was conducted in Gande county of Qinghai Province, China. Participants were recruited from August to September 2018 and from February to March 2019. A self-developed questionnaire was used to measure demographic information, ES-HL and BIPE. Hierarchical regression analysis was done to identify the factors associated with BIPE. RESULTS: In the hierarchical regression analysis, we entered age, sex, education level, marital state and family monthly income per capita into model 1 which explained a significant amount of variance in BIPE (Adjusted R2 change = 0.029, P = 0.006). Sex (ß = - 0.125, P = 0.013) and family monthly income per capita (ß = - 0.133, P = 0.009) were found to be associated with BIPE. Subsequently, the three factors of ES-HL were added to Model 1 to create Model 2. In Model 2, the two factors of ES-HL, perceived echinococcosis information support (ß = 0.229, P < 0.001) and echinococcosis-specific self-management ability (ß = 0.252, P < 0.001), were significantly associated with BIPE, while the information acquisition and evaluation ability factor (ß =0.093, P = 0.089) was not found to be associated with BIPE. The model improved significantly when ES-HL was included (Model 2) explaining the 25.8% of variance of BIPE (Adjust R2 change =0.229, P < 0.001). CONCLUSIONS: ES-HL is an important predictor of whether individuals take preventive actions against echinococcosis. An ES-HL promotion action project should be developed targeting specific populations to enhance the prevention of echinococcosis.

In vitro evaluation of albendazole-loaded nanostructured lipid carriers on Echinococcus granulosus microcysts and their prophylactic efficacy on experimental secondary hydatidosis.

To enhance the therapeutic effects of albendazole (ABZ) on Echinococcus granulosus protoscoleces and metacestodes, ABZ-loaded nanostructured lipid carriers (ABZ-NLCs) are prepared by the hot high-speed homogenization method. Protoscoleces and microcysts were treated in vitro with free ABZ and ABZ-NLCs (concentrations of 1, 5, and 10 µg/ml), and the corresponding effects were monitored by methylene blue exclusion test and scanning and transmission electron microscopy. Chemoprophylactic treatment was performed on Balb/C mice 1 day before intraperitoneal injection of viable protoscoleces. The drugs were administered daily by intragastric inoculation for a period of 30 days. The prophylactic efficacy was assessed based on the number and weight of cysts developed in treated mice. The ultrastructural alterations in cysts were examined by transmission electron microscopy. After 18 days, all the protoscoleces incubated with 10 µg/ml ABZ-NLCs were killed, while 51.25 ± 4.03% of the protoscoleces incubated with 10 µg/ml free ABZ were still viable. Microcysts treated with ABZ-NLCs underwent degenerative alterations in a shorter time than when free ABZ was applied. The mean weight of the cysts recovered from mice of ABZ-NLCs group was significantly lower than that of the free ABZ group (P < 0.05), yielding prophylactic efficacy of 92.45% and 38.53%, respectively. The cysts treated with ABZ-NLCs showed marked ultrastructural changes in the germinal layer. This study demonstrated that both in vitro and in vivo treatments with ABZ-NLCs are significantly more efficient than treatment with free ABZ against E. granulosus protoscoleces, metacestodes, and prevention of cyst development in mice.

A mathematical modelling approach for treatment and control of Echinococcus multilocularis.

Alveolar echinococcosis (AE) is a zoonotic parasitic diseases caused by a cestode parasite known as Echinococcus multilocularis. The parasite has a wildlife cycle with definitive hosts (foxes) and small mammals as intermediate hosts (rodents) while humans are the accidental hosts. Parasite infection pressure relation to time of the year and age dependent infection pressure for parasite abundance also depend on the urbanization. The aim of current work is forecasting the thresholds via the computational analysis of the disease spread which is a useful approach since it can help to design the experimental settings with better planning and efficiency. Network analysis when interlinked with the computational techniques provides better insight into the spatial and temporal heterogeneities. In the present study, a mathematical framework that describes the transmission dynamics and control measures of E. multilocularis in foxes is documented. We used treatment of foxes with baits for the prevention of the E. multilocularis infection. A novel approach of networking, called Petri net (PN), based on density dependent differential equations, is utilized during this research. The accurate description of the transmission of the parasite and the effect of drug on it is provided to the readers in this article. The transitions, which are difficult to analyse theoretically, are presented with the aid of the discrete approach of networking. A discrete mathematical framework can prove to be an accurate and robust tool to analyse and control the parasite dynamics.

Albendazole solid dispersions against alveolar echinococcosis: a pharmacotechnical strategy to improve the efficacy of the drug.

Alveolar echinococcosis is a neglected parasitic zoonosis caused by Echinococcus multilocularis. The pharmacological treatment is based on albendazole (ABZ). However, the low water solubility of the drug produces a limited dissolution rate, with the consequent failure in the treatment of the disease. Solid dispersions are a successful pharmacotechnical strategy to improve the dissolution profile of poorly water-soluble drugs. The aim of this work was to determine the in vivo efficacy of ABZ solid dispersions using poloxamer 407 as a carrier (ABZ:P407 solid dispersions (SDs)) in the murine intraperitoneal infection model for secondary alveolar echinococcosis. In the chemoprophylactic efficacy study, the ABZ suspension, the ABZ:P407 SDs and the physical mixture of ABZ and poloxamer 407 showed a tendency to decrease the development of murine cysts, causing damage to the germinal layer. In the clinical efficacy study, the ABZ:P407 SDs produced a significant decrease in the weight of murine cysts. In addition, the SDs produced extensive damage to the germinal layer. The increase in the efficacy of ABZ could be due to the improvement of water solubility and wettability of the drug due to the surfactant nature of poloxamer 407. In conclusion, this study is the basis for further research. This pharmacotechnical strategy might in the future offer novel treatment alternatives for human alveolar echinococcosis.

Identification of vulnerable populations and knowledge, attitude, and practice analysis of echinococcosis in Tibet Autonomous Region of China.

Echinococcosis is one of the 17 neglected tropical diseases recognized by the World Health Organization and causes a huge global disease burden. The Tibet Autonomous Region (Tibet) of China is the most epidemic area of echinococcosis worldwide. Echinococcosis poses an enormous threat to local public health and economic development. Identifying vulnerable populations and analyzing people's knowledge, attitudes, and practices (KAP) with respect to echinococcosis is necessary to prevent and control echinococcosis. Based on reported cases and questionnaire responses, we first used a k-prototypes clustering algorithm to identify vulnerable populations according to human demographics (including gender, age, education level, and occupation). We then used a KAP analysis to evaluate the Tibetan people's understanding of echinococcosis. The results identified three types of vulnerable population. Vulnerable population I comprised illiterate middle-aged and older women engaged in agriculture and animal husbandry. Vulnerable population II comprised illiterate middle-aged male herdsmen. Vulnerable population III comprised young male farmers with a low education level. The KAP analysis indicated that the pass rate for all participants was 72.6%, 6.4%, 95.0%, and 75.8% for KAP, K, A, and P, respectively. The pass rates were significantly different among different age and gender groups. Based on these results, it is necessary to improve public health education and professional training, and to implement effective control and management measures targeting typical hosts of echinococcosis. This study provides a direct reference for the prevention and control of echinococcosis in Tibet.

Cystic echinococcosis: Development of an intermediate host rabbit model for using in vaccination studies.

The aims of this study were an establishment of the domestic rabbit as an intermediate host for cystic echinococcosis (CE) and to evaluate the potency of the crude germinal layer and the protoscoleces antigens to protect against the CE. Firstly; Two groups of white Newzeland rabbits were infected orally either by 5000 active oncospheres or viable protoscoleces separately. After 20 weeks, the slaughtered rabbits showed the presence of hydatid cysts at different internal organs. Molecular detection of the resulted cysts was conducted. Secondly; 27 rabbits were divided into nine groups (n = 3). Groups 1 and 2 were immunized with the crude germinal layer antigen while the groups 3 and 4 were immunized with the crude protoscoleces antigen. Groups 5 and 6 received the adjuvant mineral oil. Groups 7 and 8 were used as positive control. The last 9 group was kept as a negative control. The obtained results showed a significant high protection percentage of 83.4% and high antibody titer was recorded in groups that received the crude germinal layer antigen comparing with the groups that immunized with the crude protoscoleces antigen as their protection percentage was 66.7% with lower IgG response. In conclusion, the domestic rabbits could be used as a laboratory model for CE. Developing of the germinal layer antigen is more immunogenic than the protoscoleces one and could be used as a promising vaccine. Attention should be directed towards the existing rabbit in the environment adjacent to infected dogs as it could be a part of Echinococcus life cycle.

Knowledge, attitudes and practices regarding echinococcosis in Xizang Autonomous Region, China.

BACKGROUND: Echinococcosis is a neglected zoonotic parasitic disease caused echinococcus parasitizes, poseing a significant economic burden on both humans and animals. There are limited studies on echinococcosis in China, especially Xizang Autonomous Region, although the area is endemic area for echinococcosis. The study aimed to provide information for strategic prevention against this disease. METHODS: A cross-sectional survey was conducted among the residents in Xizang Autonomous Region, China to evaluate their knowledge, attitudes and practices on endemicity of echinococcosis. A face-to-face survey was conducted to collect the data using a well-designed questionnaire. The contents included basic personal information, knowledge, attitudes and practices about echinococcosis, personal hygiene and behavior habits, dog feeding and whether they had received the information on echinococcosis, and so on. We surveyed 840 persons in practice. All data analysis was performed using Epi Info 7.2. RESULTS: Of the total particpants, 86.8% had a primary education level or below (including primary and illiterate), and even 45.0% were illiterate. Farmers and herdsmen represent the main occupations in this study. People who know all the echinococcosis-related knowledge in the questionnaire only accounted for 8.7% of the participants. However, none of the participants was aware of routes of echinococcosis infection in human or dogs. The data showed participants with higher educational background had the high awareness rate of echinococcosis-related knowledge or attitudes (chi-square for trend, χ2 = 21.23, p<0.05 & χ2 = 48.43, p<0.05). In addition, The percentage of the participant with awareness of echinococcosis-related practices was associated with their age and principle occupation (χ2 = 52.72, p<0.05 & χ2 = 20.63, p<0.05). CONCLUSIONS: Xizang Autonomous Region is an epidemic area of Echinococcosis. The prevalence of the disease has been largely due to the lack of knowledge, awareness, and poor hygiene practice in local residences. Therefore, effective disease prevention education and awareness campaigns in community will be significantly helpful in prevention and control of echinococcosis.

Combining proteomics and bioinformatics to explore novel tegumental antigens as vaccine candidates against Echinococcus granulosus infection.

Echinococcus granulosus is the parasite responsible for cystic echinococcosis (CE), an important worldwide-distributed zoonosis. New effective vaccines against CE could potentially have great economic and health benefits. Here, we describe an innovative vaccine design scheme starting from an antigenic fraction enriched in tegumental antigens from the protoscolex stage (termed PSEx) already known to induce protection against CE. We first used mass spectrometry to characterize the protein composition of PSEx followed by Gene Ontology analysis to study the potential Biological Processes, Molecular Functions, and Cellular Localizations of the identified proteins. Following, antigenicity predictions and determination of conservancy degree against other organisms were determined. Thus, nine novel proteins were identified as potential vaccine candidates. Furthermore, linear B cell epitopes free of posttranslational modifications were predicted in the whole PSEx proteome through colocalization of in silico predicted epitopes within peptide fragments identified by matrix-assisted laser desorption/ionization-TOF/TOF. Resulting peptides were termed "clean linear B cell epitopes," and through BLASTp scanning against all nonhelminth proteins, those with 100% identity against any other protein were discarded. Then, the secondary structure was predicted for peptides and their corresponding proteins. Peptides with highly similar secondary structure respect to their parental protein were selected, and those potentially toxic and/or allergenic were discarded. Finally, the selected clean linear B cell epitopes were mapped within their corresponding 3D-modeled protein to analyze their possible antibody accessibilities, resulting in 14 putative peptide vaccine candidates. We propose nine novel proteins and 14 peptides to be further tested as vaccine candidates against CE.

In vitro effects of Artemisia sieberi on Echinococcus granulosus protoscolices.

Hydatidosis is a parasitic zoonotic disease. Surgery is one of its treatment modalities during which protoscolices are likely to be released into the peritoneal cavity and cause recurrence of the disease. Given the above problem and the complications associated with conventional anti-parasitic agents, it is imperative to find an effective and natural protoscolicidal agent. The present study was conducted to evaluate effects of Artemisia sieberi on Echinococcus granulosus protoscolices. Protoscolices were collected from slaughtered livestock in Kerman abattoir and the effect of three concentrations of aqueous extract of A. sieberi (25 mg ml-1, 50 mg ml-1 and 75 mg ml-1) was assessed over three different exposure periods. Results showed that scolicidal effect of this extract at exposure periods of 2, 5 and 10 min was 76 ±â€¯1.4, 76.8 ±â€¯1.41 and 85.7 ±â€¯3.29 percent at concentration of 25 mg ml-1 and 76.8 ±â€¯1.4, 78 ±â€¯3.18 and 86.4 ±â€¯24.9 percent at concentration of 50 mg ml-1 and finally 80 ±â€¯2.73, 90 ±â€¯0.79 and 92.6 ±â€¯1.27 percent at concentration of 75 mg ml-1, respectively. It can be concluded that the aqueous extract of A. sieberi has a protoscolicidal activity and can be considered a natural agent against hydatid cyst protoscolices.

Albendazole-lipid nanocapsules: Optimization, characterization and chemoprophylactic efficacy in mice infected with Echinococcus granulosus.

Cystic echinococcosis (CE), which is caused during the metacestode larval stage of Echinococcus granulosus, is a life-threatening disease and is very difficult to treat. At present, the FDA-approved antihelmintic drugs are mebendazole (MBZ), albendazole (ABZ) and its principal metabolite ABZ sulfoxide (ABZSO), but as these have a therapeutic efficacy over 50%, underlining the need for new drug delivery systems. The aim of this work was the optimization and characterization of previously developed ABZ lipid nanocapsules (ABZ-LNCs) and evaluate their efficacy in mice infected with E. granulosus. LNCs were prepared by the phase inversion technique and characterized in terms of size, surface charge, drug loading, and in vitro stability followed by an in vivo proof-of-concept using a murine model infected with E. granulosus. Stable particle dispersions with a narrow size distribution and high efficiency of encapsulation (≥90%) were obtained. ABZ-LNCs showed a greater chemoprophylactic efficacy than ABZ suspension administered by the oral route as 4 out of the 10 ABZ-LNCs treated mice did not develop any cysts, whereas the infection progressed in all mice from the ABZ suspension group. Regarding the ultrastructural studies of cysts, mice treated with ABZ-LNCs or ABZ suspension revealed changes in the germinal layer. However, the extent of the damage appeared to be greater after ABZ-LNC administration compared to the suspension treatment. These results suggest that ABZ-LNCs could be a promising novel candidate for ABZ delivery to treat CE.

Community perception and knowledge of cystic echinococcosis in the High Atlas Mountains, Morocco.

BACKGROUND: Cystic echinococcosis (CE), a neglected zoonosis caused by the larval stage of the tapeworm Echinococcus granulosus, remains a public health issue in many developing countries that practice extensive sheep breeding. Control of CE is difficult and requires a community-based integrated approach. We assessed the communities' knowledge and perception of CE, its animal hosts, and its control in a CE endemic area of the High Atlas Mountains, Morocco. METHODS: We conducted twenty focus group discussions (FGDs) stratified by gender with villagers, butchers and students in ten Berber villages that were purposefully selected for their CE prevalence. RESULTS: This community considers CE to be a severe and relatively common disease in humans and animals but has a poor understanding of the parasite's life cycle. Risk behaviour and disabling factors for disease control are mainly related to cultural practices in sheep breeding and home slaughtering, dog keeping, and offal disposal at home, as well as in slaughterhouses. Participants in our focus group discussions were supportive of control measures as management of canine populations, waste disposal, and monitoring of slaughterhouses. CONCLUSIONS: The uncontrolled stray dog population and dogs having access to offal (both at village dumps and slaughterhouses) suggest that authorities should be more closely involved in CE control. This study also highlights the need for improved knowledge about the transmission cycle of the parasite among communities and health professionals. Inter-sectoral collaboration between health staff, veterinarians, and social scientists appears to be crucial for sustainable control of this parasitic zoonosis.

Oral Application of Recombinant Bacillus subtilis Spores to Dogs Results in a Humoral Response against Specific Echinococcus granulosus Paramyosin and Tropomyosin Antigens.

Bacillus subtilis is known as an endospore- and biofilm-forming bacterium with probiotic properties. We have recently developed a method for displaying heterologous proteins on the surface of B. subtilis biofilms by introducing the coding sequences of the protein of interest into the bacterial genome to generate a fusion protein linked to the C terminus of the biofilm matrix protein TasA. Although B. subtilis is a regular component of the gut microflora, we constructed a series of recombinant B. subtilis strains that were tested for their ability to be used to immunize dogs following oral application of the spores. Specifically, we tested recombinant spores of B. subtilis carrying either the fluorescent protein mCherry or else selected antigenic peptides (tropomyosin and paramyosin) from Echinococcus granulosus, a zoonotic intestinal tapeworm of dogs and other carnivores. The application of the recombinant B. subtilis spores led to the colonization of the gut with recombinant B. subtilis but did not cause any adverse effect on the health of the animals. As measured by enzyme-linked immunosorbent assay and immunoblotting, the dogs were able to develop a humoral immune response against mCherry as well as against E. granulosus antigenic peptides. Interestingly, the sera of dogs obtained after immunization with recombinant spores of E. granulosus peptides were able to recognize E. granulosus protoscoleces, which represent the infective form of the head of the tapeworms. These results represent an essential step toward the establishment of B. subtilis as an enteric vaccine agent.

Limitations of the Echinococcus granulosus genome sequence assemblies for analysis of the gene family encoding the EG95 vaccine antigen.

Echinococcus granulosus is an important zoonotic parasite that is distributed worldwide. The EG95 vaccine was developed to assist with control of E. granulosus transmission through the parasite's livestock intermediate hosts. The vaccine is based on a recombinant antigen encoded by a gene which is a member of a multi-gene family. With the recent availability of two E. granulosus draft genomes, we sought to map the eg95 gene family to the genomes. We were unable to map unequivocally any of the eg95 gene family members which had previously been characterized by cloning and sequencing both strands of genomic DNA fragments. Our inability to map EG95-related genes to the genomes has revealed limitations in the assembled sequence data when utilized for gene family analyses. This study contrasts with the expectations expressed in often high-profile publications describing draft genomes of parasitic organisms, highlighting deficiencies in currently available genomic resources for E. granulosus and provides a cautionary note for research which seeks to utilize these genome datasets.

Current status and future prospective of vaccine development against Echinococcus granulosus.

Cystic echinococcosis (CE) is one of the most important zoonotic parasite diseases in human, livestock, and wildlife worldwide. Development of effective vaccines against CE appears to be the most promising strategy to control this infectious disease. Use of potential livestock and canine vaccines against the larval and adult stage of E. granulosus life cycle may be the key to the production of powerful vaccines. Some progress has been accomplished in the development of vaccines against hydatidosis using empirical approaches, while such immunotherapies often fail to induce adequate immune responses. Therefore, it is of great interest to identify antigens (Ags) with high immunogenicity and develop effective vaccines and adjuvant constructs against CE. To this end, various tools can be applied, including immune-based genomics and proteomics, immunoinformatics, systems vaccinology and mathematical/computational modeling. In this review, we aimed to provide comprehensive insights upon the current status of vaccination trials against E. granulosus, and also articulate some perspectives on the production of novel anti-CE vaccines. Use of novel prospective technologies is also discussed to highlight the importance of development and advancement of the next generation vaccines against E. granulosus.