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In the 1930's Kozen Yoshino published 6 papers on Taenia solium. One of these papers is particularly important because it describes the outcomes of experimental infections with T. solium tapeworms in four volunteers, Yoshino being one of them. The paper was written in an old form of the Japanese language, making it almost inaccessible to most researchers around the world. Here we provide a non-literal translation of this work and some brief comments by the translators. Each of the four volunteers swallowed three or five cysticerci recovered from an experimentally infected pig. Each person was found to have harbored 2 - 5 tapeworms when the infections were terminated by drug treatment between 120 and 451 days after infection. The pre-patent period recorded by Yoshino's volunteers was between 62 and 72 days based on the first appearance of gravid proglottids (GPs) in the feces. In one subject, the number of GPs appearing in each bowel movement was tracked daily for 371 days following the first appearance of GPs in the feces, together with the number of bowel movements each day. GPs were observed on 275 of the 284 days on which the subject defecated during which observations were made. There was a decline in the number of GPs over the observation period; proglottids were observed on 97% of all days on which defecation occurred, they were present on 87% of days in the last month of infection. The cumulative number of GPs for a month in the 1st, 6th and 12th months of patent infection was 334, 174 and 126, respectively., Competing Interests: Declaration of Competing Interest The authors declare that there is no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Detailed post mortem analyses of 68 free-ranging, slaughter-age pigs from two sites in the Banke District of Nepal identified 36% as being infected with Echinococcus granulosus. The cysts ranged from infertile, immature cysts a few millimetres in diameter to fertile cysts >10 cm in diameter. PCR RFLP and DNA sequencing identified the cysts as being E. granulosus sensu stricto. The Banke district has recently been identified as having a high prevalence of porcine cysticercosis. These data suggest that cestode zoonoses in this, and possibly other parts of Nepal may be a serious concern for human health. An assessment of the level of human cystic echinococcosis and neurocysticercosis, in the region is warranted and the introduction of control measures are required to limit the parasites' transmission., (Copyright © 2019 Elsevier B.V. All rights reserved.)

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., (Published by Elsevier B.V.)

Taeniasis and cysticercosis are known to be endemic in several Indonesian islands, although relatively little recent epidemiological data are available. As most Indonesian people are Muslims, taeniasis/cysticercosis caused by the pork tapeworm, Taenia solium, has a restricted presence in non-Muslim societies and is endemic only among some Hindu communities on the island of Bali. Bali has long been known to be endemic for taeniasis/cysticercosis; almost a century ago levels of cysticercosis of 20-30% were described in cattle and 2-3% in pigs. Few studies of taeniasis/cysticercosis were undertaken in Bali prior to a series of research programs commenced since the 1990s. Both Taenia saginata and T. solium continue to be endemic in Bali. Molecular studies have revealed that all T. saginata-like tapeworms detected in Bali are T. saginata. No evidence has been found for the presence of Taenia asiatica in Bali. Economic, sanitary and education improvements across much of the island over the past decades have been associated with a decline in the amount of transmission of T. solium such that the parasite now seems to be restricted to the eastern part of the island, a small area on the northeastern slope of Mt. Agung, the highest mountain in Bali. The living environment including sanitation and hygiene condition in this endemic area remains relatively poor especially during the half-year dry season, and pigs continue to roam freely. In this review, historical records and ongoing projects towards elimination of taeniasis/cysticercosis in Bali are reviewed to provide a better understanding of the present situation of taeniasis/cysticercosis in Bali towards a future, cysticercosis-free tropical resort island., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Neurocysticercosis is a major cause of epilepsy in countries where Taenia solium is endemic and the parasite is a major cause of food-borne disease globally. Pigs are the natural intermediate host involved in transmission of the parasite. T. solium is known to be endemic in Nepal, however there is limited reliable data about the prevalence of the disease in Nepal. The aim of this study was to determine accurately the prevalence of porcine cysticercosis in slaughter age pigs in an area of Nepal where pigs are known to be free-roaming. Pigs were obtained from the Udaypur Village Development Committee (VDC) and Hirminiya & Betahani VDC of the Banke district in Nepal. One hundred and ten animals of slaughter age (approximately 8-16 months old) were purchased, slaughtered and the heart, liver, brain and half the body skeletal musculature were sliced using hand knives and the number and viability of T. solium cysts determined. Thirty two of the 110 animals were found to harbour T. solium cysticerci (29%), of which 30 (27%) were found to have viable cysticerci (93% of the infected animals). This is one of the highest prevalences of porcine cysticercosis that has been reported to date from the results of necropsy on randomly selected animals. This study highlights a high rate of transmission of T. solium in the Banke District of Nepal. It encourages further investigation of human and porcine cysticercosis in Nepal, as well as implementation of efforts to reduce transmission of the parasite and the associated human disease., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)

Following confirmation that a remote village of approximately 300 inhabitants in northern Lao PDR was hyperendemic for the Neglected Tropical Disease Taenia solium, a pilot human-porcine therapeutic control intervention was implemented between October 2013 and November 2014. Mass drug administration with a three day albendazole 400mg protocol was offered to all eligible humans in October 2013 and March 2014. At these times, and again in October 2014, eligible village pigs received the anti-cysticercosis TSOL18 vaccination and an oral dose of oxfendazole anthelmintic at 30mg/kg, both repeated one month later. Community and individual human taeniasis prevalences were estimated via copro-antigen ELISA of volunteered human faecal samples prior to October 2013, and again in January 2015, in order to examine the short term impact of the intervention., (Copyright © 2016 The Author(s). Published by Elsevier B.V. All rights reserved.)

Following confirmation that a remote village of approximately 300 inhabitants in northern Lao PDR was hyperendemic for the Neglected Tropical Disease Taenia solium, a pilot human-porcine therapeutic control intervention was implemented between October 2013 and November 2014. Mass drug administration with a three day albendazole 400mg protocol was offered to all eligible humans in October 2013 and March 2014. At these times, and again in October 2014, eligible village pigs received the anti-cysticercosis TSOL18 vaccination and an oral dose of oxfendazole anthelmintic at 30mg/kg, both repeated one month later. Community and individual human taeniasis prevalences were estimated via copro-antigen ELISA of volunteered human faecal samples prior to October 2013, and again in January 2015, in order to examine the short term impact of the intervention., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)

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., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Neurocysticercosis due to Taenia solium infection is an important cause of human morbidity and mortality. Despite the availability of effective anthelmintics, the disease remains prevalent in many parts of the world and there is a need for new and improved measures for control of the infection. An effective vaccine to prevent infection in pigs, the parasite's natural intermediate host, would be a valuable new option to assist with T. solium control. Several approaches are being used currently towards the development of a T. solium vaccine and these approaches are reviewed briefly, with emphasis on the use of recombinant oncosphere antigens. Highly effective vaccines have been developed against cysticercosis in sheep and cattle caused by Taenia ovis and Taenia saginata, respectively. This success has encouraged the adoption of a similar strategy for T. solium. The recent finding that one oncosphere antigen, TSOL18, can induce complete protection against T. solium infection in pigs, highlights the potential for development of a practical vaccine. A vision is proposed for the development of a safe, effective, inexpensive vaccine for pigs, which can be administered in an edible form. Through an international collaborative effort, research is progressing towards the realisation of such a vaccine and its use to reduce the global burden of neurocysticercosis.

A vaccine to protect sheep, goats, and bovines against hydatid disease caused by the cysts of Echinococcus granulosus is prepared as a recombinant fusion protein expressed in Escherichia coli. Solubilised inclusion bodies are injected, together with Quil A, subcutaneously on two occasions 1 month or more apart, and induce protection against infection which lasts for at least 12 months. A third injection given 6-12 months after the second injection induces a high and long-lasting protection against artificial or natural challenge infections. This review describes work carried out on the formulation, safety and efficacy of the vaccine under laboratory and field conditions, using artificial or natural challenges with E. granulosus eggs, followed by necropsy. Hydatid control programmes based on regular treatment of all dogs with the correct dose of a highly-efficient anthelmintic have sometimes not been successful in Continental environments. Access to dogs is difficult in summer because of the distances to summer pastures, and is often impossible in winter because of snow. A control program using strategic twice-yearly anthelmintic treatment of dogs is likely to be successful provided grazing animals are vaccinated as well. Vaccination as a control tool only requires the veterinarians to visit two times a year, and while the veterinarian is present, the dogs can be treated with anthelmintic for little additional cost. One visit should take place after the autumn kill of animals for winter consumption, and this is a good time to vaccinate animals born in the summer, and also all other animals while they are healthy and immunologically responsive. The other visit should take place in the spring, at which time animals born during winter can be vaccinated. Although a single immunization has been shown to induce a useful degree of protection, where possible it is best to give two initial injections, 1 month apart. If it is possible for veterinarians to stay in the field for 2 months in November/December and March/April, in order to give the two injections, a more rapid onset of full protective immunity will initially be achieved than if the injections are given 6 months apart. A large-scale safety and efficacy trial involving 50,000 and 100,000 lambs in Qinghai and Xinjiang Provinces of China has taken place. Results have confirmed safety and efficacy. In most countries, prevalence of infection increases with age. The vaccine has no effect on established cysts, and therefore, in order to prevent the biomass of Echinococcus spp. from increasing, it might be an effective strategy to begin a control programme by vaccinating all animals. Because many of the older stock will already be infected, they will remain a source of infection for dogs for the average lifetime of the stock. Dogs will still be able to be infected from the older stock, and will continue to infect humans. We advocate that a vaccination programme be accompanied by education about hydatid disease, and anthelmintic treatment of dogs in late autumn and early spring.

Hydatid patients were investigated for the presence of specific serum antibodies against a recombinant Echinococcus granulosus antigen, designated myophilin. The clinical history of each patient was examined to determine any correlation between factors such as cyst location and medical treatment on the presence or absence of antibodies to myophilin. Specific antibodies against recombinant myophilin were detected by Western blot analysis in 38.8% (7 of 18) of the hydatid patients examined. These patients also had the highest titres in ELISA against sheep hydatid cyst fluid antigen. There was an association between the presence of antibodies to myophilin and the patients having undergone recent treatment by chemotherapy and/or surgery, suggesting that the destruction of hydatid cysts may lead to an immune response against myophilin.

Using immunoassay and immunoblotting approaches, antibodies to Sj26, a glutathione S-transferase molecule (Mr = 26,000) of Schistosoma japonicum worms that is a vaccine candidate, have been sought in three large human serum banks. For these studies, a near-native recombinant Sj26 molecule produced in Escherichia coli was used, generally in ELISAs. Anti-Sj26 activity was detected readily in a high proportion of the sera at titres below 1:400 and appeared to be largely protein A-binding IgG antibodies. No differences in the prevalence of anti-Sj26 antibodies were noted in sera from entirely normal individuals or those with a variety of parasitic infections, but never exposed to S. japonicum. The stimulus responsible for induction of these low titre, probably low affinity antibodies in humans remains unknown.