Biliary Taeniasis: Case Series and Literature Review

Biliary taeniasis is uncommon in clinical practice. We report two cases in our hospital. The first patient was diagnosed with acute biliary pancreatitis. Endoscopic retrograde cholangiopancreatography (ERCP) showed a white, flat, segmented 1-cm-wide tapeworm drilling into the duodenal papilla that was identified as Taenia saginata. After tapeworm removal, bile duct sweeping, and anthelmintic therapy, the patient recovered uneventfully. The second patient was diagnosed with acute cholangitis and multiple stones in the common bile duct and gallbladder. Emergency ERCP showed no tapeworm in the duodenum. During a subsequent ERCP 6 days later, a flat tapeworm, also T. saginata, was identified drilling into the duodenal papilla. We review five patients cases with acute acalculous cholecystitis or cholangitis caused by T. saginata or Taenia solium, and 1 patient with T. saginata drilling into the T-tube. Taeniasis should be taken into consideration when dealing with biliary and pancreatic disease.

Impact of a 3-year mass drug administration pilot project for taeniasis control in Madagascar

Taenia solium is endemic in Madagascar and presents a significant burden on the population and the health system. The parasite cycles through humans who host the adult tapeworm, and pigs that host the larval stages. Accidental infection of humans may occur with the larval stages which encyst in the nervous central system causing neurocysticercosis, a major cause of seizure disorders and a public health problem. One of the interventions to facilitate the control of the disease is mass drug administration (MDA) of the human population with taeniacide. Here we describe a pilot project conducted in Antanifotsy district of Madagascar from 2015 to 2017 where three annual rounds of MDA (praziquantel, 10mg/Kg) were undertaken in 52 villages. Changes in the prevalence of taeniasis were assessed before, during and after the treatments. A total of 221,308 treatments were given to all eligible people above 5 years of age representing a 95% coverage of the targeted population. No major adverse effects were notified related to the implementation of the MDA. The prevalence of taeniasis was measured using Kato-Katz and copro-antigen techniques. Analyses undertaken combining the results of the Kato-Katz with copro-antigen, or using the Kato-Katz results alone, showed that there was a significant reduction in taeniasis 4 months after the last MDA, but 12 months later (16 months after the last MDA) the taeniasis prevalence had returned to its original levels. Results of the pilot project emphasize the need of a multi-sectorial One-Health approach for the sustained control of T. solium.

The parasite Taenia solium causes neurocysticercosis in humans in its larval stage and is the main cause of seizure disorders in poor communities that keep pigs (the intermediate host). Diagnosis and treatment of neurocysticercosis remains beyond the reach of the general population in Madagascar. Prevention is therefore the most suitable strategy for combating this disease. Mass drug administration (MDA) is used to treat communities for several parasitic diseases such as schistosomiasis. Infection with the T. solium tapeworm in people can be treated with MDA using praziquantel. Here, we conducted a pilot project in Madagascar, giving over 220,000 treatments to people in 52 villages once per year, for 3 consecutive years. The effects on taeniasis seemed to be encouraging when assessed 4 months after finishing the treatment, but 16 months later, the parasite’s prevalence had returned to its original level. MDA was effective in providing temporary control of taeniasis, but parasite transmission was not interrupted. With respect to T. solium, this highlights the need of incorporating other interventions such as vaccination and medication in pigs, improved pig husbandry and meat inspection to tackle the whole cycle of the parasite.

Taenia solium Cysticercosis and Its Impact in Neurological Disease

Taenia solium neurocysticercosis (NCC) is endemic in most of the world and contributes significantly to the burden of epilepsy and other neurological morbidity. Also present in developed countries because of immigration and travel, NCC is one of few diseases targeted for eradication. This paper reviews all aspects of its life cycle (taeniasis, porcine cysticercosis, human cysticercosis), with a focus on recent advances in its diagnosis, management, and control. Diagnosis of taeniasis is limited by poor availability of immunological or molecular assays. Diagnosis of NCC rests on neuroimaging findings, supported by serological assays. The treatment of NCC should be approached in the context of the particular type of infection (intra- or extraparenchymal; number, location, and stage of lesions) and has evolved toward combined symptomatic and antiparasitic management, with particular attention to modulating inflammation. Research on NCC and particularly the use of recently available genome data and animal models of infection should help to elucidate mechanisms of brain inflammation, damage, and epileptogenesis.

Systematic review of the effectiveness of selected drugs for preventive chemotherapy for Taenia solium taeniasis

Background

Preventive chemotherapy is a useful tool for the control of Taenia solium taeniasis and cysticercosis. The aim of this systematic review is to assess the scientific evidence concerning the effectiveness and safety of different drugs in preventive chemotherapy for T. solium taeniasis in endemic populations.

Methods

A systematic review was conducted of controlled and uncontrolled studies, assessing the efficacy and adverse effects (among other outcomes) of albendazole, niclosamide and/or praziquantel for preventive chemotherapy of T. solium taeniasis. A comprehensive search was conducted for published and unpublished studies. Two reviewers screened articles, completed the data extraction and assessment of risk of bias. A meta-analysis of cure rate and relative reduction in prevalence was performed. The protocol for this review was registered on the International prospective register of systematic reviews (PROSPERO), number CRD42018112533.

Results

We identified 3555 records, of which we included 20 primary studies reported across 33 articles. Meta-analyses of drug and dose showed that a single dose of praziquantel 10mg/kg, albendazole 400mg per day for three consecutive days, or niclosamide 2g, resulted in better cure rates for T. solium taeniasis (99.5%, 96.4% and 84.3%, respectively) than praziquantel 5mg/kg or single dose albendazole 400mg (89.0% and 52.0%, respectively). These findings have a low certainty of evidence due to high risk of bias in individual studies and heterogeneity in combined estimates. In relation to side-effects, most studies reported either no or only mild and transient side-effects within the first three days following drug administration for all drugs and doses.

Conclusion

Evidence indicated that praziquantel 10mg/kg, niclosamide 2g, and triple dose albendazole 400mg were effective as taenicides and could be considered for use in mass drug administration programs for the control of T. solium taeniasis. Evidence was not found that any of these drugs caused severe side effects at the indicated doses, although the extent of the available evidence was limited.

Taeniasis and cysticercosis caused by Taenia solium are considered, by the WHO, to be neglected tropical diseases. Preventive chemotherapy for taeniasis in endemic populations is a useful tool for control of the parasite. Preventive chemotherapy can be implemented by treating the whole population in endemic areas at regular intervals (known as mass drug administration). While different drugs, doses and regimes have been used there were still uncertainties about which drugs and dose have the best efficacy while considering adverse effects. We conducted a systematic review of the best available literature to inform a WHO guideline for preventive chemotherapy. We found that praziquantel 10mg/kg, niclosamide 2g, and triple dose albendazole 400mg (400mg per day for three consecutive days) are all effective. Proven side-effects were mild and short-lived, when they did occur.

Human Tapeworm from Simalungun, Indonesia

A 46-years-old man from Indonesia, resides in Nagori Dolok Village, Silau Kahaean Subdistrict, Simalungun District, Sumatra Utara Province, had of spontaneous discharge of tapeworm segments (proglottids) from anus almost every day for ten years. There were 1-5 segments which can move actively discharge per day. Although he feels embarrassed about the condition, no significant symptoms were found, and physical examination was within normal limits. Clinical diagnosis of Taeniasis was made on October 20, 2017, and subsequently received oral Praziquantel 600 mg tablet single dose and 5 mg of oral Bisacodyl. Four hours later, the patient was defecated. The stool was collected in plastic and filtered with a filter device to collect any tapeworm segments.A full segment of tapeworm as long as 2.86 meters were found. Microscopic examination was done to identify the egg worms, proglottids, and scolex. Dye substance was injected into a mature gravid proglottid through the genital pore and pressed in two object-glasses to identify the reproductive organs. Microscopic examination (400x magnification) of this sample revealed that the number of uterine branches and testes in a proglottid were 16 pairs. The number of uterine branches in T. solium are 8-12 pairs and T. saginata are 18-32 pairs.The filtered stool was moved into a container and carefully observed. A soft yellowish-white material of 1.5 mm in diameter was found, which turned out to be the head of the tapeworm called Scolex. Microscopic examination of scolex revealed that the rostellum was absent. A segment called 'snout' was found at the apex. The functions were probably as a sense of smell and vacuum organ.The patient was lived in Simalungun, North Sumatera, some tribe in that area has a long tradition of culinary called 'Hinasumba', consist of raw pork liver and meat, and 'Naiholat' consist of poorly cooked pork.Even though pig was determined as an intermediate host, the type of tapeworm was not consistent with T.solium. The patient had the long history of infection but never had sign or symptoms of neurocystecercosis. Based on etno-geographical condition, the patient was infected by T.asiatica. Microscopic examination of the uterus and scolex indicate that the tapeworm had most similarity to T.asiatica.Amin et al.8 from Bangladesh in 2009 reported a case of T. asiatica in human with total strobila length was 1.5 meters. Macroscopic morphology (length:width) of gravid proglottid segment of T.saginata is 3:1, T. solium 1.5:1. The tapeworm that we discovered had 1-1.5:1 ratio (2.5 cm length and 2 cm width).Some features of the tapeworm (no rostellum, present of the snout, and fix number of theuterus in every proglottid) were not found in three existing type of Taenia species. Further microscopic and molecular study should be done to determined type or subtype of the tapeworm. A case of taeniasis asiatica who had completed treatment was reported. Macroscopic and microscopic was done to support the clinical diagnosis.

Mathematical model of the life cycle of taenia-cysticercosis: transmission dynamics and chemotherapy (Part 1)

BACKGROUND

Taenia solium is the aetiological agent of human taeniasis, pig cysticercosis and human neurocysticercosis, which are serious public health problems, especially in developing countries.

METHODS

A mathematical model of the transmission dynamics of taeniasis-cysticercosis is formulated. The model consists of a coupled system of differential equations, which are density-dependent equations for describing the flow of the parasite through the life cycle. The model is hybrid since it comprises deterministic equations with stochastic elements which describe changes in the mean parasite burden and incorporates the overall pattern of the parasites' distribution.

RESULTS

Sensitivity and bifurcation analyses were carried out to determine the range of values of the model. The model can reproduce the observed epidemiological patterns of human taeniasis, pig and human cysticercosis. For example, for a wide range of parameter values, the mean intensity of adult worms tends to rapidly stabilize in one parasite per individual host. From this model, we also derived a Susceptible-Infected model to describe the prevalence of infection in humans and pigs. Chemotherapeutic interventions against pig cysticercosis or human taeniasis may reduce rapidly and effectively the mean intensity of human taeniasis, pig cysticercosis and human cysticercosis. This effect can be achieved even if the protective efficacy of the drug is of the order of 90% and the coverage rate is 90%. This means that health in humans infected either with adult worms or cysticerci may be achieved by the application of anthelmintic drugs against pig cysticercosis. However, treatment against human cysticercosis alone, does not influence neither human teniasis nor pig cysticercosis. This is because human cysticercosis infection does not influence the value of the basic reproductive number (Ro).

CONCLUSIONS

Even coverage of 100% in the administration of anthelmintics did not eliminate the infection. Then elimination of the infection in all hosts does not seem a feasible goal to achieve by administering only chemotherapeutic interventions. Throughout the manuscript a discussion of our model in the context of other models of taeniasis-cysticercosis is presented.

Assessment of a computer-based Taenia solium health education tool 'The Vicious Worm' on knowledge uptake among professionals and their attitudes towards the program

Health education has been recognised as a specific intervention tool for control of Taenia solium taeniosis/cysticercosis but evaluation of the efficacy of the tool remains. The aim of our study was to assess the effect of a computer-based T. solium health education tool 'The Vicious Worm' on knowledge uptake among professionals and investigate attitudes towards the program. The study was carried out between March and May 2014 in Mbeya Region, Tanzania, where T. solium is endemic. The study was a pre and post assessment of a health education tool based on questionnaire surveys and focus group discussions to investigate knowledge and attitudes. A total of 79 study subjects participated in the study including study subjects from both health- and agriculture sector. The health education consisted of 1½h individual practice with the computer program. The baseline questionnaire showed an overall knowledge on aspects of acquisition and transmission of T. solium infections (78%), porcine cysticercosis treatment (77%), human tapeworm in general (72%), neurocysticercosis in general (49%), and porcine cysticercosis diagnosis (48%). However, there was a lack of knowledge on acquisition of neurocysticercosis (15%), prevention of T. solium taeniosis/cysticercosis (28%), and relation between porcine cysticercosis, human cysticercosis, and taeniosis (32%). Overall, the study subject's knowledge was significantly improved both immediately after (p=0.001) and two weeks after (p<0.001) the health education and knowledge regarding specific aspects was significantly improved in most aspects immediately after and two weeks after the health education. The focus group discussions showed positive attitudes towards the program and the study subjects found 'The Vicious Worm' efficient, simple, and appealing. The study revealed a good effect of 'The Vicious Worm' suggesting that it could be a useful health education tool, which should be further assessed and thereafter integrated in T. solium taeniosis/cysticercosis control.

Control of Taenia solium taeniasis/cysticercosis: The best way forward for sub-Saharan Africa?

Taenia solium taeniasis/cysticercosis is a neglected parasitic zoonosis with significant economic and public health impacts. Control measures can be broadly grouped into community health education, improvements in hygiene and sanitary conditions, proper meat handling at household and community level, improved standards of meat inspection, pig management, treatment of individual patients and possibly human populations, and treatment and/or vaccination of porcine populations. This manuscript looks critically into currently existing control options and provides suggestions on which (combination of) tools would be most effective in the control of T. solium taeniasis/cysticercosis in sub-Saharan Africa. Field data and disease transmission simulations suggest that implementation of a single intervention control strategy will not lead to a satisfactory reduction of disease morbidity or transmission. A feasible strategy to combat T. solium taeniasis/cysticercosis would include a combination of approaches focussing on both human (health education and treatment) and animal host (management, treatment and vaccination), which can vary for different communities and different geographical locations. Selection of the specific strategy depends on cost-effectiveness analyses based on solid field data, currently unavailable, though urgently needed; as well as on health priorities and resources of the country. A One Health approach involving medical, veterinary, environmental and social sectors is essential for T. solium to be controlled and eventually eliminated. Finally the success of any intervention is largely dependent on the level of societal and political acceptance, commitment and engagement.

CystiSim - An Agent-Based Model for Taenia solium Transmission and Control

Taenia solium taeniosis/cysticercosis was declared eradicable by the International Task Force for Disease Eradication in 1993, but remains a neglected zoonosis. To assist in the attempt to regionally eliminate this parasite, we developed cystiSim, an agent-based model for T. solium transmission and control. The model was developed in R and available as an R package (http://cran.r-project.org/package=cystiSim). cystiSim was adapted to an observed setting using field data from Tanzania, but adaptable to other settings if necessary. The model description adheres to the Overview, Design concepts, and Details (ODD) protocol and consists of two entities—pigs and humans. Pigs acquire cysticercosis through the environment or by direct contact with a tapeworm carrier's faeces. Humans acquire taeniosis from slaughtered pigs proportional to their infection intensity. The model allows for evaluation of three interventions measures or combinations hereof: treatment of humans, treatment of pigs, and pig vaccination, and allows for customary coverage and efficacy settings. cystiSim is the first agent-based transmission model for T. solium and suggests that control using a strategy consisting of an intervention only targeting the porcine host is possible, but that coverage and efficacy must be high if elimination is the ultimate goal. Good coverage of the intervention is important, but can be compensated for by including an additional intervention targeting the human host. cystiSim shows that the scenarios combining interventions in both hosts, mass drug administration to humans, and vaccination and treatment of pigs, have a high probability of success if coverage of 75% can be maintained over at least a four year period. In comparison with an existing mathematical model for T. solium transmission, cystiSim also includes parasite maturation, host immunity, and environmental contamination. Adding these biological parameters to the model resulted in new insights in the potential effect of intervention measures.

Taenia solium is the leading cause of preventable epilepsy and the highest ranking foodborne parasite in terms of disease burden worldwide. Currently there are no large scale control programmes implemented against T. solium, but efficacious intervention tools are there, making control programmes the next step forward. Because of the zoonotic properties of the parasite, existing in both humans and pigs, a combination of intervention tools is likely to be needed. cystiSim is an agent-based disease model that provides insight into which intervention tools, and the frequency of administration of these tools, are needed to yield an effect on disease prevalence. cystiSim is a valuable tool in designing future control programmes and will assist in the elimination of T. solium as a public health problem.

TAENIA SAGINATA INFECTION IN A 14-MONTH-OLD TODDLER

A 14-month-old female toddler presented with a 3-day history of pass- ing gravid proglottids of Taenia saginata. Neither she nor her family members had a history of eating raw beef or other raw meat. Single doses of praziquantel and niclosamide were administered. To the best of our knowledge, this is the youngest described patient with T. saginata infection to date.

SCHISTOSOMICIDAL ACTIVITY OF THE CRUDE EXTRACT OF ARTOCARPUS LAKOOCHA

Puag-Haad is a traditional anthelmintic drug used to treat taeniasis in Thailand and Lao PDR. It is derived from the aqueous extract of the plant Artocarpus lakoocha. We investigated the in vitro anthelmintic properties of Puag-Haad against Schistosoma mansoni. Adult worms were incubated in M-199 medium containing 250, 500 and 750 μg/ml of Puag-Haad or praziquantel (PZQ) at a concentration of 175 μg/ml for 3, 6, 12 and 24 hours. The relative motility (RM value), survival index (SI) and tegument alterations seen under scanning electron microscope were assessed at each incubation time. The results showed the crude extract of A. lakoocha at a concentration of 250 μg/ml was more effective in causing damage than PZQ at a concentration of 175 μg/ml using RM and SI values. The major target organ affected by Puag-Haad was the tegument. The damage was greater at higher concentrations of the crude extract. It is likely tetrahydroxystilbene (THS), the main compound in Puag-Haad, caused the damage. THS could be a future candidate as a schistosomal drug. Further studies are needed to explore its mechanism, efficiency and safety in vivo.

Mini review on chemotherapy of taeniasis and cysticercosis due to Taenia solium in Asia, and a case report with 20 tapeworms in China

A 43-year-old Tibetan woman living in northwest Sichuan, China, confirmed to be a taeniasis carrier of Taenia solium was treated with pumpkin seeds combined with Areca nut extract in October 2009. All 20 tapeworms except one without scolex were expelled under good conditions. She was free of secondary cysticercosis within one year follow up. Although the first choice for treatment of taeniasis is still praziquantel, it may often cause serious side effect on asymptomatic cysticercosis cases to suddenly become symptomatic within a half day of the treatment. Therefore, the problems in treatment of taeniasis and/or cysticercosis in Asia are briefly overviewed, since other platyhelminthic diseases including schistosomiasis, opisthorchiasis etc. are more common and praziquantel is strongly recommended for mass treatment of these trematodiases with no idea on the co-infection with eggs of T. solium which cause asymptomatic cysticercosis.

Genotoxicity induced by Taenia solium and its reduction by immunization with calreticulin in a hamster model of taeniosis

Genotoxicity induced by neurocysticercosis has been demonstrated in vitro and in vivo in humans. The adult stage of Taenia solium lodges in the small intestine and is the main risk factor to acquire neurocysticercosis, nevertheless its carcinogenic potential has not been evaluated. In this study, we determined the genotoxic effect of T. solium infection in the hamster model of taeniosis. In addition, we assessed the effect of oral immunization with recombinant T. solium calreticulin (rTsCRT) plus cholera toxin as adjuvant on micronuclei induction, as this protein has been shown to induce 33-44% protection in the hamster model of taeniosis. Blood samples were collected from the orbital venous plexus of noninfected and infected hamsters at different days postinfection, as well as from orally immunized animals, to evaluate the frequency of micronucleated reticulocytes as a measure of genotoxicity induced by parasite exposure and rTsCRT vaccination. Our results indicate that infection with T. solium caused time-dependent DNA damage in vivo and that rTsCRT immunization reduced the genotoxic damage induced by the presence of the tapeworms.

Oral expulsion of taenia worm by a pregnant lady

The case of a pregnant lady who expelled a tapeworm orally is discussed and a brief review on Taeniasis is also presented.

Long-term Taenia saginata infection successfully treated with meglumine/diatrizoate sodium

A 46-year-old Japanese man visited our hospital for chronic abdominal pain, persistent diarrhea and discharge of proglottids for 7 years. He had been living in Lao People's Democratic Republic. Ileography using meglumine/diatrizoate sodium (Gastrografin) revealed a long tapeworm. A Taenia saginata including the scolex was excreted through the intestinal tract by the administration of total 780 ml of Gastrografin. Taeniasis is an important disease in the differential diagnosis of imported diseases in Japan. Parasite infection should be suspected in patients with chronic abdominal pain or persistent diarrhea regardless of the findings for small bowel obstruction when there is a history of overseas travel.

Progesterone induces mucosal immunity in a rodent model of human taeniosis by Taenia solium

More than one quarter of human world's population is exposed to intestinal helminth parasites. The Taenia solium tapeworm carrier is the main risk factor in the transmission of both human neurocysticercosis and porcine cysticercosis. Sex steroids play an important role during T. solium infection, particularly progesterone has been proposed as a key immunomodulatory hormone involved in susceptibility to human taeniosis in woman and cysticercosis in pregnant pigs. Thus, we evaluated the effect of progesterone administration upon the experimental taeniosis in golden hamsters (Mesocricetus auratus). Intact female adult hamsters were randomly divided into 3 groups: progesterone-subcutaneously treated; olive oil-treated as the vehicle group; and untreated controls. Animals were treated every other day during 4 weeks. After 2 weeks of treatment, all hamsters were orally infected with 4 viable T. solium cysticerci. After 2 weeks post infection, progesterone-treated hamsters showed reduction in adult worm recovery by 80%, compared to both vehicle-treated and non-manipulated infected animals. In contrast to control and vehicle groups, progesterone treatment diminished tapeworm length by 75% and increased proliferation rate of leukocytes from spleen and mesenteric lymph nodes of infected hamsters by 5-fold. The latter exhibited high expression levels of IL-4, IL-6 and TNF-α at the duodenal mucosa, accompanied with polymorphonuclear leukocytes infiltration. These results support that progesterone protects hamsters from the T. solium adult tapeworm establishment by improving the intestinal mucosal immunity, suggesting a potential use of analogues of this hormone as novel inductors of the gut immune response against intestinal helminth infections and probably other bowel-related disorders.

Taeniasis/cysticercosis in Bali, Indonesia

Taenia solium and Taenia saginata are found in humans in Bali, Indonesia. During a field survey of 660 people in Bali from 2002-2009 of taeniasis/cysticercosis cases using mitochondrial DNA confirmation of the species, we detected 80 cases of T. saginata taeniasis, 2 dual T. saginata/T. solium infections with T. solium metacestodes in the brain and 12 neurocysticercosis (NCC) cases at Sanglah Hospital, Denpasar. Although the prevalence of NCC in Bali is low, sporadic cases are still present. There is no Taenia asiatica in Bali. We summarize here the field survey findings of taeniasis, including 1 dual infection with taeniasis and cysticercosis in 2007, and the reason why there are no T. asiatica cases and we describe 3 NCC cases admitted to Sanglah Hospital, Denpasar, Bali in 2004. Diagnosis was based on anamnesis, clinical examination, including CT Scan, histopathological, serological and mitochondrial DNA examinations. In order to prevent unexpected symptomatic NCC after treatment with praziquantel, we recommend introducing a rapid test to confirm taeniasis carriers and cysticercosis cases as a tool for real time diagnosis.

[Environmental spread of Taenia proglottids: an atypical yet interesting public health problem in schools]

We report herein a new case of teniasis caused by Taenia saginata (tapeworm) in a pediatric patient with done-on-purpose dispersion of proglottids happened in an elementary school inside the health district ASL CN-1. This new case highlights how teniasis in children is not as rare, as it is not so rare dispersal of proglottids in the environment, made on purpose, by the same subjects that have been parasitized. The environmental dispersion of proglottids is an important public health problem that requires a rapid and joint management of the problem aiming to identify the parasite as quickly as possible, given the different pathogenic larval stage of three species of tapeworm that can infest the man.

Tribendimidine and albendazole for treating soil-transmitted helminths, Strongyloides stercoralis and Taenia spp.: open-label randomized trial

Background

Tribendimidine is an anthelminthic drug with a broad spectrum of activity. In 2004 the drug was approved by Chinese authorities for human use. The efficacy of tribendimidine against soil-transmitted helminths (Ascaris lumbricoides, hookworm, and Trichuris trichiura) has been established, and new laboratory investigations point to activity against cestodes and Strongyloides ratti.

Methodology/Principal Findings

In an open-label randomized trial, the safety and efficacy of a single oral dose of albendazole or tribendimidine (both drugs administered at 200 mg for 5- to 14-year-old children, and 400 mg for individuals ≥15 years) against soil-transmitted helminths, Strongyloides stercoralis, and Taenia spp. were assessed in a village in Yunnan province, People's Republic of China. The analysis was on a per-protocol basis and the trial is registered with controlled-trials.com (number ISRCTN01779485). Both albendazole and tribendimidine were highly efficacious against A. lumbricoides and, moderately, against hookworm. The efficacy against T. trichiura was low. Among 57 individuals who received tribendimidine, the prevalence of S. stercoralis was reduced from 19.3% to 8.8% (observed cure rate 54.5%, p = 0.107), and that of Taenia spp. from 26.3% to 8.8% (observed cure rate 66.7%, p = 0.014). Similar prevalence reductions were noted among the 66 albendazole recipients. Taking into account “new” infections discovered at treatment evaluation, which were most likely missed pre-treatment due to the lack of sensitivity of available diagnostic approaches, the difference between the drug-specific net Taenia spp. cure rates was highly significant in favor of tribendimidine (p = 0.001). No significant adverse events of either drug were observed.

Conclusions/Significance

Our results suggest that single-dose oral tribendimidine can be employed in settings with extensive intestinal polyparasitism, and its efficacy against A. lumbricoides and hookworm was confirmed. The promising results obtained with tribendimidine against S. stercoralis and Taenia spp. warrant further investigations. In a next step, multiple-dose schedules should be evaluated.

More than a billion people are infected with intestinal worms and, in the developing world, many individuals harbor several kinds of worms concurrently. There are only a handful of drugs available for treatment, and drug efficacy varies according to the worm species. We compared the efficacy of a single oral dose of tribendimidine, a new broad-spectrum worm drug from China, with the standard drug albendazole for the treatment of hookworm, large roundworm (Ascaris lumbricoides), whipworm (Trichuris trichiura) and, for the first time, Strongyloides stercoralis and tapeworm (Taenia spp.). Our single-blind randomized trial was conducted in a village in Yunnan province, southwest China. Both drugs showed high efficacy against A. lumbricoides and a moderate efficacy against hookworm. Among 57 tribendimidine recipients, the prevalence of S. stercoralis was reduced from 19.3% to 8.8%, and that of Taenia spp. from 26.3% to 8.8%. Similar prevalence reductions were noted among the 66 albendazole recipients. Taking into account additional infections only discovered at treatment evaluation, the difference between the drug-specific Taenia spp. net cure rates was highly significant in favor of tribendimidine. In view of our promising results, multiple-dose schedules with tribendimidine against S. stercoralis and Taenia spp. should be evaluated next.

Strategies for the elimination of taeniasis/cysticercosis

Advances in the field of neurocysticercosis continue to shape our understanding of the disease and our efforts to control it. Several attempts have been made to eradicate the disease with active interventions such as changing domestic pig-raising practices, mass chemotherapy of porcine cysticercosis and taeniasis, selective detection and treatment of taeniasis, and community health education. Moreover, ongoing progress in the diagnosis of taeniasis and the development of a porcine vaccine against cysticercosis in Australia, Mexico and Peru has yielded at least one effective vaccine that is currently available. Thus far, however, attempted interventions have only been successful in temporarily disrupting transmission of the disease. Controlled data on the efficacy and acceptability of the different interventions is urgently needed to provide a base-line schematic for intervention which could later be tailored to each particular endemic scenario.

Taeniasis and its socio-economic implication in Awassa town and its surroundings, Southern Ethiopia

OBJECTIVE

The study was conducted between October 2005 and April 2006 in Awassa town and its surroundings to investigate the status of T. saginata taeniasis, its socio-economic importance and potential risk factors.

METHODS

Questionnaire survey was conducted on 120 volunteer individuals selected at random. Additionally, retrospective study on taenicidal drugs inventories at 12 pharmaceutical shops was conducted.

RESULTS

T. saginata taeniasis was a wide spread problem in the town and its surroundings with overall prevalence of 64.2% (77 out of 120) and maximum infection frequencies of five times per year. The prevalence of taeniasis was significantly varied between religion, occupation, raw meat consumption and use of spices with raw meat. Accordingly, Christian communities (OR = 5.2, 95% CI = 1.20-22.50), high-risk groups (OR = 4.05, 95% CI = 1.27-12.93), raw meat consumers (OR = 7.9, 95% CI = 2.46-5.66), and spices users (OR = 11.6, 95% CI = 2.85-47.28) had higher likelihood of acquiring taeniasis than Muslim communities, low risk groups, cooked meat eaters and non-spices users, respectively. Conversely, prevalence was not varied between sex, age, marital status and educational backgrounds of the respondents. Respondents' preferences to available taenicidal drugs had strong linear relationship with drug dose sold (R2 = 0.92), and showed that Niclosamide (46.8%) was the drug of first choice while Praziquantel (13%) was the least preferred drug. The taenicidal drug doses and treatment cost from 2002 to 2005 were estimated to be 4,913,346 adult doses and 820,343 USD (7,219,021 Eth. Birr as per rate of 2006).

CONCLUSION

Taeniasis was a wide spread problem with higher prevalence and frequent infections in the town and its surroundings. Sociocultural conditions and occupation were the major risk factors for the occurrence of the disease. Hence, owing to its public health and economic importance, taeniasis deserves serious attention in order to safeguard the public health.

Control of Taenia solium cysticercosis/taeniosis

Cysticercosis is emerging as a serious public health and agricultural problem in many poorer countries of Latin America, Africa, and Asia. Caused by the pork tapeworm, Taenia solium, this zoonotic disease forms larval cysts in humans and pigs that can lead to epilepsy and death in humans, reduces the market value of pigs and makes pork unsafe to eat. It occurs where pigs range freely, sanitation is poor, and meat inspection is absent or inadequate, and is thus strongly associated with poverty and smallholder farming. Although theoretically easy to control and declared eradicable cysticercosis remains neglected in most endemic countries due to lack of information and awareness about the extent of the problem, suitable diagnostic and management capacity, and appropriate prevention and control strategies. Human neurocysticercosis occurs when the larval cysts develop in the brain. It is considered to be the most common parasitic infection of the human nervous system and the most frequent preventable cause of epilepsy in the developing world. Thus far the infection has not been eliminated from any region by a specific program, and no national control programs are yet in place. We consider the tools available for combating cysticercosis and suggest simple packages of interventions, which can be conducted utilizing existing services and structures in the endemic countries to provide appropriate and sustainable control of the disease.

A case of Taenia saginata (tape worm) infestation of the uterus presenting with abnormal vaginal bleeding

There are many reported causes of abnormal uterine bleeding. We report an unusual case of uterine bleeding caused by tapeworm infestation, mimicking retained products of conception in a 35 year old multipara.

[Therapeutic alternatives in case of failure of first-line treatment of intestinal helminthiasis in adults]

Development of antiparasite medications over the last 15 years has greatly reduced the number of treatment failures for intestinal helminthiasis. Benzimidazole derivatives, ivermectine, praziquantel and triclabendazole are easy to use, well tolerated and generally curative. First-line treatment are currently so reliable that failure should lead first to investigation of possible "false failure" causes such as misdiagnosis, poor identification of the parasite, inadequate or incorrect treatment, and repeat contamination, before concluding that genuine parasite resistance is involved and that alternative therapy is needed. Nitazoxanide is an alternative treatment for fascioliasis and teniasis. Albendazole can be beneficial for taeniasis and strongyloidiasis. Metronidazole can be effective for fascioliasis. Artemisinine derivatives are useful for schistosomiasis. Combined therapies are necessary for refractory ankylostomiasis.

Combined human and porcine mass chemotherapy for the control of T. solium

A combined (human and porcine) mass chemotherapy program was tested in a controlled design in 12 village hamlets in the Peruvian highlands. A single dose of 5 mg of praziquantel was given to eliminate intestinal taeniasis in humans, and two rounds of oxfendazole (30 mg/kg) were administered to all pigs. The total population in the study villages was 5,658 resident individuals, and the porcine population at the beginning of the study was 716 pigs. Human treatment coverage was 75%, ranging from 69% to 80%. There were only a few refusals of owners for porcine treatment of their animals. The effect of the intervention was measured by comparing incidence rates (seroconversion in pigs who were seronegative 4 months before) in treatment versus control villages, before and up to 18 months after treatment. There was a clear effect in decreasing prevalence (odds ratio, 0.51; P < 0.001) and incidence (odds ratio, 0.39; P < 0.013) in the treatment area after the intervention, which did not leave to extinction of the parasite but stabilized in slightly decreased rates persisting along the follow-up period. Mass chemotherapy was effective in decreasing infection pressure in this hyperendemic area. However, the magnitude of the effect was small and did not attain the goal of eliminating transmission.

Progress in diagnosis, treatment and elimination of echinococcosis and cysticercosis

Here I review the current status of geographical occurrence and public health significance of echinococcosis (Echinococcus spp. infections) and cysticercosis (Taenia solium infection) with special emphasis on the remarkable technologic progress achieved in recent decades that has led to greater understanding of the biology and epidemiology of these cestode infections. The greatest remaining challenges are to apply this knowledge and technology to improved medical management and prevention of these infections.

[Case report: taeniasis, is it a cause of psychiatric and neural symptoms?]

The most frequent symptom of taeniasis is the discharge of proglottids (93.7%). Gravid proglottids which do not have uterine pores are damaged when they exit the anus by their movement. Because of this damage most of the eggs contaminate the perianal tract. The cellophane tape technique that is used for getting perineum material is also a convenient technique for diagnosis of taeniasis. A 36 year-old woman was admitted to our parasitology clinic complaining of a watering mouth for one year, of abdominal pain, and of loss of appetite for 6 months, and who had discharged proglottids from time to time. She had been eating raw meat since her childhood and had had treatment for taeniasis fifteen years ago. She has also been under treatment for obsessive and compulsive neurosis and depression for two years and complained of constipation that was the side effect of the drug clomipramine HCL. She was given treatment with niclosamide and purgative treatment. The result of the treatment was incomplete because the patient refused to use the purgative. She was called for follow up controls two weeks and six months after treatment and after six months did not have any evidence of infection in her stools. When she was asked, the patient said that she did not need to use the drugs for the treatment of obsessive and compulsive neurosis and depression any more since her symptoms had decreased. According to various authorities, taeniasis is thought to be the cause of psychiatric symptoms due to its neural and psychological effects. These claims have been confirmed in our case because of her psychiatric symptoms decreased after the taeniasis treatment. Thus, the view that there is a relationship between intestinal parasites and psychiatric disease has been strengthened.

Role of chemotherapy of taeniasis in prevention of neurocysticercosis

Neurocysticercosis (NC) is a serious public health problem in Taenia solium endemic areas and in some immigrants and international travelers. A key intervention in preventing NC is elimination of taeniasis by chemotherapy. Currently, two safe and effective taenicides, namely niclosamide and praziquantel, are available. Both are on WHO Essential Drug list, but are often inaccessible in T. solium endemic areas. Natural remedies, still widely used in some endemic areas, are frequently carcinogenic or highly toxic and as such should be discontinued. Chemotherapeutic intervention to control T. solium taeniasis/cysticercosis, whilst theoretically feasible, has several practical obstacles. These include poor public awareness, problems with diagnosing Taenia carriers, poor availability of taenicides where needed and low priority afforded to the control of NC. These can be overcome, respectively, by effective health education, wider use of newly developed coproantigen tests, strengthening of health services infrastructure and essential drugs distribution, and increasing the priority given to prevention of NC, as a leading cause of epilepsy in T. solium endemic areas. Information is accumulating on rational approaches to population-based short-term chemotherapeutic control measures. These are: widely available modern diagnostic tools and taenicides, treatment of any case of taeniasis, confirmed or probable, focus-oriented chemotherapy, irrespective of Taenia species implicated, improved sanitation, cooperation of veterinary and medical services, linkage with programs against epilepsy and cooperation of better educated communities. Now, it remains to take an advantage of existing tools and experience.

Inquérito epidemiológico sobre teníase em população do programa saúde da família no município de Uberaba, MG

Foi realizado inquérito para avaliar alguns aspectos epidemiológicos da teníase em 100.144 indivíduos do Programa Saúde da Família. Foram identificados 185 (0,2%) indivíduos com antecedentes de teníase. Destes, 112 (60,5%) receberam tratamento com praziquantel. Em 97 (86,6%) dos casos, houve eliminação de proglotes que corresponderam a Taenia saginata e Taenia solium em 36 (37,1%) e 4 (4,1%), respectivamente.

Therapy for common parasitic diseases in pregnancy in the United States: a review and a survey of obstetrician/gynecologists' level of knowledge about these diseases

A number of food- and waterborne parasitic diseases that are common in the United States can adversely impact women during pregnancy. Therapeutic considerations during pregnancy for these diseases are reviewed. Also, the level of knowledge of obstetrician-gynecologists about diagnosis and treatment of these diseases (toxoplasmosis, cryptosporidiosis, giardiasis, amebiasis, cyclosporiasis, trichinellosis, ascariasis, and taeniasis) was estimated by means of a questionnaire developed by the Centers for Disease Control and Prevention (CDC) and the American College of Obstetricians and Gynecologists (ACOG). Of the 1200 obstetrician-gynecologists surveyed, 521 (43%) responded. In general, respondents gave correct answers to questions about toxoplasmosis, but for other illnesses responses, it varied. For example, most (61.4%) respondents gave incorrect answers about treatment of cryptosporidiosis in pregnancy, and many (41.2%) respondents incorrectly identified metronidazole as the safest treatment for giardiasis in the first trimester of pregnancy. Although knowledge among obstetrician-gynecologists about toxoplasmosis is good, there is a wide variation in knowledge about other common food- and waterborne parasitic diseases that are likely to be encountered in the United States. Therapeutic considerations for these diseases during pregnancy are discussed.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to list the various common protozoal diseases, to outline the clinical manifestations as well as route of spread for each of the protozoal diseases, and to outline potential therapies for each of the protozoal diseases.

Appendiceal taeniasis presenting like acute appendicitis

A case of parasitic appendicitis caused by Taenia sp. in a 28-year-old woman from Brazil is reported. Histopathological data and a description of the helminthe found in the appendix lumen are presented.

[Preclinical studies of cucurbita maxima (pumpkin seeds) a traditional intestinal antiparasitic in rural urban areas]

Experimental research was carried out at the Parasitology and Chemistry laboratories of the Jorge Basadre Grohmann National University, in Tacna. The process involved two phases: (1) determination of the minimum inhibitory concentration (MIC) of Cucurbita Maxima as an antiparasitic agent using canine tapeworms with an intestinal isolation of 5 to 6 hours, and (2) determination of the side-effects of Curbita Maxima on exposed albino rats. It was found that the MIC of 23 gr. of pumpkin seed in 100 ml. of distilled water can produce an antihelminthic effect. This concentration is equivalent to +/- 73 pumpkin seeds (x2 = 5.6, p<0.01). Macroscopically, alterations in helminthic motility are present at a dose of > 23 gr. There is a protheolithic effect with an average survival time of 38.4 minutes. Microscopically the mature proglottids present a destruction of the tegument involving the basal membrane. In the gravid proglottids there is egg destruction. These findings are accentuated when experimenting with Cucurbita Maxima in a concentration of 30 and 32 gr. Superficial non-erosive gastritis was found in weys rats after 4 hours of administering 9 gr/kg.

[Clinical study and electron microscope observation of tapeworm scolices on 548 cases of taeniasis treated with Binlang Chengqi Decoction]

OBJECTIVE

To observe the effect and mechanism of Chinese herbs in the treatment of taeniasis.

METHODS

Five hundred and forty-eight cases of taeniasis were treated with Binlang Chengqi Decoction (BLCQD). The tapeworm scolices of ten cases were observed by electron microscope (EM).

RESULTS

Among the 548 cases, 521 cases were cured and 27 cases were improved. The total effective rate was 100%. Foam-like secretion in the sucker of the tapeworm scolices and erosion of the epithelium in the cervical part were observed by scanning electron microscope. Observed by transmission electron microscope, the cortex was seriously damaged. The microvilli were exfoliated. The cells in the muscle layer and parenchyma layer were injured in various degrees. The mitochondria were tumefied or caved. And the nerve cord was damaged.

CONCLUSION

BLCQD can not only paralyze the tapeworm scolex, but also injury the cells of the tapeworm scolex.

[Management of taeniasis: comparative evaluation of osmotic non-oily purgatives]

The therapeutic protocol in taeniasis associates an anthelmintic drug and a pro-expulsive purgative. The purgative impeds intestinal disaggregation of the worm, facilitating the identification of the species of Taenia and preventing the risk of cysticercosis in case of T. solium infection.

AIM

Comparative evaluation of the efficacy of two non-oily purgatives (magnesia usta MU and a lactulose derivative DL) using as anti-parasitic drug exclusively Praziquantel (PZQ), in order to update the treatment of human taeniasis.

RESULTS

Regardless the purgative used, cestode shedding rate was of 100% fractionated, with easy to identify cysticerci, but with seldom recognizable scolex. Expulsion is rapid, up to 3 hours with DL and maximum 6 hours for MU, being perceived as uncomfortable, but without major intolerance. Egg shedding following expulsion may be prolonged up to 48 hours, with a significant risk for the patient and the community if T. solium infection. The onset of non-specific post-taeniasis entero-colonic disease was signalled as possible functional sequel.

CONCLUSION

The treatment formula for taeniasis with PZQ and an non-oily purgative (preferably DL, yet also MU as cheaper option) ensures rapid and safe expulsion of the worm, allowing meanwhile the morphological diagnostic of species. Controlled expulsion of the taenia demands specialised surveillance in hospital.

Unusual manifestations of Taenia solium infestation

We present two rare cases of unusual manifestations of Taenia solium infestation. Taenia infestation usually causes abdominal pain and diarrhea in humans. But there have been no clinical reports of ascites, chronic diarrhea, and malabsorption due to Taenia solium without evidence of the ova or larvae of the parasites in stool examinations. Our first unusual case was in a 30-year-old woman with spontaneous pneumothorax, pleural effusion, and ascites; the second case was in a 67-year-old man with a 3-year history of diarrhea, weight loss, and indigestion. Both patients showed blood eosinophilia and positive serologic tests for Taenia solium. After antiparasitic agent administration, their symptoms resolved successfully.

Species identification after treatment for human taeniasis

Identification of species of human tapeworms is crucial because the consequences of infection by Taenia solium and T saginata are very different. However, evacuation of species-identifiable tapeworms is uncommon and Taenia spp eggs are indistinguishable under the microscope. Treatment of taeniasis consists of niclosamide followed by a purgative. Recently, we adopted preniclosamide and postniclosamide electrolyte-polyethyleneglycol salt (EPS) purges to improve bowel cleaning. Retrospective comparison of traditional castor oil with EPS purge showed that recovery of the tapeworm scolex was significantly improved (20 of 68 vs none of 46, p=0.0001) in the EPS group. Furthermore, 42 of 68 (62%) individuals receiving EPS excreted identifiable gravid proglottids. EPS treatment helps the visual identification of Taenia spp.

Case of megaloblastic anemia caused by intestinal taeniasis

A 61-year-old eutrophic male was diagnosed with vitamin B12 deficiency and megaloblastic anemia. A modified Schilling test suggested intestinal malabsorption unrelated to intrinsic factor deficiency. Subsequent colonoscopy revealed the presence of a Taenia tapeworm. The anemia resolved within days under therapy with niclosamide and temporary vitamin B12 supplements. The present case suggests that, in addition to other well-known parasitic agents, e.g., Diphyllobothrium latum and Giardia lamblia, Taenia infestation can also be a cause of intestinal vitamin B12 malabsorption.

Taenia solium cysticercosis

The larval stage of the pork tapeworm (Taenia solium) infects the human nervous system, causing neurocysticercosis. This disease is one of the main causes of epileptic seizures in many less developed countries and is also increasingly seen in more developed countries because of immigration from endemic areas. Little information is available on the natural evolution of taeniasis or cysticercosis. Available therapeutic measures include steroids, treatments for symptoms, surgery, and, more controversially, antiparasitic drugs to kill brain parasites. Efforts to control and eliminate this disease are underway through antiparasitic treatment of endemic populations, development of pig vaccines, and other measures.

Taenia tapeworms: their biology, evolution and socioeconomic significance

A biological context for understanding human pathogens and parasites emanates from evolutionary studies among tapeworms of the genus Taenia. Human taeniasis and cysticercosis represent archaic associations and remain significant challenges for socioeconomic development, public health and food safety, and a continuing threat to animal production on a global basis.

Intestinal helminthes infestation in pregnancy: a case report and literature review

BACKGROUND

Pregnancy and parasitic infection are globally prevalent conditions that frequently coexist. Most pregnant patients with intestinal parasitic infections may be managed without antiparasitic chemotherapy.

CASE

Shortly after a visit to her nation of origin, a 22-year-old native of Ethiopia presented during her first trimester with gastrointestinal complaints and worms in her stool, which were identified as Taenia. Microscopic examination of her stool also demonstrated Strongyloides stercoralis larvae, likely the residue of an infection that had occurred several years prior to her presentation. She was treated with appropriate antihelmenthic agents, and her subsequent prenatal course has been uncomplicated.

CONCLUSION

The ability of Strongyloides to sustain an intestinal infection through autoinvasion and to cause serious disease (hyperinfection syndrome) among certain hosts makes it unique among intestinal helminths. In this case, the patient was treated to manage her symptoms and prevent subsequent Strongyloides hyperinfection.

[Efficacy and tolerance of trichlorophene in hymenolepiasis and taeniarinchiasis]

The paper deals with the clinical trials of the anthelmintic trichlorofen. The clinical and parasitological efficacy and tolerance of the agent for hymenolepiasis and taeniarinchiasis were studied. Twelve patients with hymenolepiasis and 5 with taeniarinchiasis were examined. Trichlorofen was shown to be effective in treating these infections, fairly tolerated and convenient for outpatient treatment. Eleven of the 12 with hymenolepiasis and 5 with taeniarinchiasis were cured.