Treatment Of Cysticercosis Research Articles

Effect of fluorine substituents in 4-(1-benzyl-1H-benzo[d]imidazol-2-yl)thiazole for the study of antiparasitic treatment of cysticercosis on the taenia crassiceps model

Effect of fluorine substituents in 4-(1-benzyl-1H-benzo[d]imidazol-2-yl)thiazole for the study of antiparasitic treatment of cysticercosis on the taenia crassiceps model

Preformulation and Long-Term Stability Studies of an Optimized Palatable Praziquantel Ethanol-Free Solution for Pediatric Delivery.

To date, the treatment for cysticercosis and neurocysticercosis consists of a single oral intake of praziquantel (5-10 mg/kg), which since it is only available as tablets, hinders its administration to pediatric patients. Praziquantel is a poorly water-soluble drug which represents a challenge for its formulation in solution, particularly for the pediatric population. Thus, this study aimed to develop a palatable solution for praziquantel using pharmaceutical-accepted co-solvent systems. A design of experiments approach was applied to identify the optimal conditions for achieving a suitable amount of praziquantel in solution using co-solvent mixtures. Thus, praziquantel solubility increased from 0.38 up to 43.50 mg/mL in the optimized system. A taste masking assay in healthy human volunteers confirmed a successful reduction of drug bitterness after the addition of selected flavors and a sweetener. Stability studies were also conducted at different temperatures (4, 25, and 40 °C) for 12 months Even though the presence of the three known impurities of praziquantel was observed, their amounts never exceeded the acceptance criteria of the USP. Thus, this novel approach should be considered a valuable alternative for further preclinical studies considering the high prevalence of this infection worldwide.

DETERMINATION OF THE CHRONIC TOXICITY PARAMETERS OF THE COMPLEX REMEDY FOR THE TREATMENT OF CYSTICERCOSIS IN RABBITS

The article presents the data of a preclinical test of a means for the treatment of cysticercosis in rabbits by intra-gastric administration to white mice. Cysticercus pisiformis is a disease caused by ingestion of eggs of Taenia pisiformis in food or water, a tapeworm that parasitizes the small intestine of dogs and other carnivores. As a result of the invasion, the body loses its ability to fully function, the resistance of the immune system to infectious diseases decreases. In order to avoid the spread of the disease, it is necessary to make a timely diagnosis. The obtained data can be used to take the necessary measures against infestations and are important to prevent the selective use of anti-parasitic agents, which can lead to anthelmintic resistance.
 The purpose of the work was to determine the parameters of chronic toxicity of the developed complex anti-parasitic agent for the treatment of rabbits for cysticercosis on white mice under experimental conditions.
 The animals of the experimental groups were given an aqueous mixture of 0.0002 dm3 of the drug containing the following doses of the drug daily for 12 days: 1/100 DL50 ‒ 16.80 mg/kg (I group); 1/50 DL50 ‒ 33.58 mg/kg (II group); 1/25 DL50 ‒ 67.18 mg/kg (III group). On the next day after the last administration of the drug, on mice, under the condition of light ether narcosis, blood samples were taken for morphological and biochemical studies.
 The agent for the treatment of cysticercosis in rabbits, at doses of 1/50 DL50 and 1/25 DL50, resulted in a slight decrease in hemoglobin content and erythrocyte count compared to the control, but it did not suppress bone marrow erythropoiesis in laboratory animals. A decrease in the number of lymphocytes and a slight increase in the level of neutrophils were recorded, which indicates the irritating effect of increased doses of the active substance of the drug. According to the classification of chemical substances by degree of danger (DST 12.1.007–76), it belongs to the class of "moderately toxic substances".

Validation of high performance liquid chromatography coupled to mass spectrometry to determine albendazole sulfoxide in human plasma

Context: Albendazole is used in the treatment of cysticercosis and hydatid disease, and its prolonged administration can generate adverse effects attributed to the active metabolite, albendazole sulfoxide (ABZSO), whose measurement requires validated methods that help monitor patients under treatment. Aims: To validate a high-performance liquid chromatography method with mass detection (HPLC-MS) for the determination of ABZSO in human plasma. Methods: HPLC-MS was performed on C18 columns (100 × 4.6 mm × 3.5 µm) and mobile phase composed of methanol, water and ammonia solution (25%) (800:200:0.1 v /v/v) at a flow rate of 0.5 mL/minute. The calibration curve was built with an albendazole standard, and detection in a triple quadrupole system. Results: The method was linear (1-1500 ng/mL, R2 = 0.999) with a detection limit of 1 ng/mL. ABZSO concentrations at 1, 5, 50, 100, 200, 500, 1000, and 1500 ng/mL had relative standard deviations of 10.4, 8.4, 7.8, 2.9, 7.4, 3.2, 3.4 and 1.3%. It was highly precise with a mean coefficient of variation of 1.411%, and accurate with a bias of -14.7; 2.8 and -0.8% in ABZSO concentrations of 5, 500 and 1000 ng/mL. The average recovery was 89.2%, and the stability of ABZSO after refrigeration had an average coefficient of variation of 2.3%. Conclusions: The HPLC-MS method is valid and reliable to determine ABZSO, and could be used in pharmacokinetic, bioequivalence, and other studies that evaluate the biological monitoring of patients receiving oral treatment with albendazole.

Asymptomatic isolated intramuscular cysticercosis in diabetic patient: a case report

Cysticercosis is an endemic disease in multiple areas of the world, caused by ingestion of embryonated eggs of Taenia solium. We reported a case of a 66-year old diabetic male presenting with decrease of consciousness and “rice grain” calcification in both hemithorax and neck soft tissue region, without findings of cysticercosis in computed tomography (CT) scan. Cysticercosis most commonly affects the central nervous system, causing neurocysticercosis (NCC), while solitary intramuscular cysticercosis without involvement of the central nervous system is rare. Treatment of cysticercosis is indicated for symptomatic patients, including NCC surgery is indicated in patients with neurovascular compromise caused by growth of cyst. Recognizing the signs and symptoms of cysticercosis is crucial for diagnosis and treatment in endemic areas where Taenia solium is prevalent.

Disseminated Cysticercosis-Should we treat?

Disseminated cysticercosis is defined by the presence of multiple vesicular cystic lesions in the brain with cysts demonstrable in at least two other body parts. The exact course of disseminated cysticercosis is not known and the individual cysts either become inflamed or calcify. A patient's quality of life is often poor and disseminated cysticercosis treatment is far from satisfactory. Anecdotal reports have suggested dual antiparasitic therapy to be beneficial for treating diffuse parenchymal neurocysticerci and might be worth trying in patients with massively infiltrating disseminated cysticercosis with concomitant corticosteroids.

Intraperitoneal and intracranial experimental cysticercosis present different metabolic preferences after treatment with isolated or combined albendazole and nitazoxanide

Cysticercosis is a zoonotic public health issue especially severe when the parasite is in the central nervous system although it may be found all over the human organism. Taenia crassiceps cysticerci inoculated in mice is the experimental model used to study cysticercosis. The most used cysticercosis treatment is with albendazole (ABZ). Nitazoxanide (NTZ) has been experimentally tested against this parasite. Metabolic analysis has been used to determine drugs impact on the parasite. The aim of this study was to determine the in vivo metabolic impact of the ABZ-NTZ combination in T. crassiceps cysticerci inoculated in mice peritoneal and intracranial cavities. Mice were experimentally inoculated with T. crassiceps cysticerci in the intraperitoneal cavity or in the intracranial one. Thirty days after the infection they were treated with NaCl 0.9% (control group), 50 mg/kg of ABZ, 50 mg/kg of NTZ or 50 mg/kg of NTZ and ABZ (ABZ/NTZ combination). 24 h after treatment the animals were euthanized and the cysticerci analyzed through high performance chromatography and spectrophotometry in order to detect the glycolytic, mitochondrial and protein catabolism pathways. The intracranial parasites used more intensely the homolactic fermentation while the intraperitoneal ones presented a greater use of the mitochondrial pathways and protein catabolism. Regarding the glycolytic pathways, it was possible to observe a significant impact induced by the drugs used, both isolated or in combination. It was possible to detect an increase in the fumarate reductase pathway after the drugs exposure and no impact in the protein's catabolism. Therefore, the cysticerci showed different uses of metabolic pathways regarding the site of inoculation due to the availability of nutrients inherent of each environment. This study showed the parasite metabolic resilience and capability of use of different biochemical pathways in order to ensure survival in spite of a hostile environment.

‘Starry sky’ appearance on brain CT in neurocysticercal encephalitis

A 12-year-old boy, living in a tropical area, with no medical history, presented to the emergency department for generalized seizures evolving over a period of 6 months. Intermittent moderate headaches and decreased visual acuity for 3 months were also reported. A cerebral computed tomography (CT) scan showed the presence of multiple millimetric hyperdense spots spread over the whole brain parenchyma (white matter, grey matter, basal ganglia), giving the appearance of a ‘starry sky’ (Figure 1A). Some of these hyperdensities were contained in a vesicle corresponding to a scolex (Figure 1B). There was focal white matter inflammation (Figure 1C). All of these findings allowed the diagnosis of cysticercosis encephalitis. Antiepileptic treatment associated with intravenous methylprednisolone was started for 1 week, with a decrease in the headaches and seizures. The patient was discharged with oral prednisolone, and antiepileptic and antiparasitic drugs. Cysticercosis is a parasitic infection by the larval phase of Taenia solium with possible central nervous system or other involvement. It is more frequent in tropical environments with poor hygiene conditions and pork consumption (Tale et al., 2017Tale S. Chhabria B.A. Gawalkar A.A. Banavath H.N. Bhalla A. ‘Sleeping under the starry sky’—cysticercal encephalitis.QJM Int J Med. 2017; 110: 833-834Crossref PubMed Scopus (2) Google Scholar). Cysticercosis encephalitis is a form of neurological presentation in patients with multiple cysts where there is reactive brain inflammation after the cyst dies either spontaneously or after treatment (Tale et al., 2017Tale S. Chhabria B.A. Gawalkar A.A. Banavath H.N. Bhalla A. ‘Sleeping under the starry sky’—cysticercal encephalitis.QJM Int J Med. 2017; 110: 833-834Crossref PubMed Scopus (2) Google Scholar). Neurocysticercosis can be parenchymal, intraventricular, subarachnoid, or spinal. The parenchymal localization is mainly manifested by seizures, whereas the intraventricular localization is responsible for intracranial hypertension (Garcia et al., 2014bGarcia H.H. Nash T.E. Del Brutto O.H. Clinical symptoms, diagnosis, and treatment of neurocysticercosis.Lancet Neurol. 2014; 13: 1202-1215https://doi.org/10.1016/S1474-4422(14)70094-8Abstract Full Text Full Text PDF PubMed Scopus (256) Google Scholar). The starry sky appearance on brain imaging is found in the case of numerous calcified neurocysticercosis lesions and testifies to a high parasite load. Treatment should initially include corticosteroid therapy and avoid antiparasitic treatment, which may exacerbate the inflammatory response and increase symptoms (Garcia et al., 2014aGarcia H.H. Gonzales I. Lescano A.G. Bustos J.A. Pretell E.J. Saavedra H. et al.Enhanced steroid dosing reduces seizures during antiparasitic treatment for cysticercosis and early after.Epilepsia. 2014; 55: 1452-1459https://doi.org/10.1111/epi.12739Crossref PubMed Scopus (40) Google Scholar).

In Vivo Treatment with the Combination of Nitazoxanide and Flubendazole Induces Gluconeogenesis and Protein Catabolism in Taenia crassiceps cysticerci.

Cysticercosis is the presence of Taenia solium larvae in humans or swines tissues. It is a public health problem related to bad hygienic habits and consumption of infected pork. T. crassiceps is a widely used cysticercosis experimental model. The combination of two effective drugs such as nitazoxanide (NTZ) and flubendazole (FBZ) may potentialize their effect. The aim of this study was to use biochemical analysis to determine the metabolic impact of the combination of NTZ and FBZ on cysticerci inoculated intraperitoneally in mice. Balb/c mice intraperitoneally infected with T. crassiceps cysticerci received a single oral dose NTZ/FBZ (50mg/kg). 24h after the treatment the cysticerci were removed, frozen and analyzed by high performance liquid chromatography regarding the detection of the following metabolic pathways: glycolysis, gluconeogenesis, homolactic fermentation, tricarboxylic acid cycle, proteins catabolism and fatty acids oxidation. The treatment with the drugs combination induced a statistically significant increase in gluconeogenesis and in protein catabolism when compared to the control groups. The drugs combination is potentialized and capable of causing greater metabolic stress than the separate treatment with NTZ or FBZ, showing its potential for an alternative cysticercosis treatment.

Taenia solium insulin receptors: promising candidates for cysticercosis treatment and prevention

Insulin signaling pathway is an ancient and highly conserved pathway known to play critical roles in cell growth, control and metabolic regulation. In this study, we identified and characterized two insulin receptor genes (TsIR-1316 and TsIR-4810) from Taenia solium. TsIR-1316 was grouped with E. multilocularis insulin receptor (EmIR-1) and TsIR-4810 was closer to Taenia pisiformis insulin-like growth factor receptor (TpIR) on the same branch with a very high bootstrap value. TsIR-1316 was located on the integument of larvae and adult worms, as well as the ovary of adults and eggs. Alternatively, TsIR-4810 was located in the parenchyma and reproductive organs of the adult worms. By using in vitro cultivation systems with Cysticercus pisiformis as a model, we demonstrated that anti-TsIRs-LBD antibodies could effectively block the insulin signaling pathway, resulting in reduced phosphorylation of the insulin receptor as well as lower levels of glucose uptake and glycogen synthesis. The rabbits immunized with TsIR-1316-LBD, TsIR-4810-LBD and TsIR-1316-LBD + TsIR-4810-LBD produced protection against infection of T. pisiformis as demonstrated by a 94.6%, 96% and 80% reduction of establishment of larvae, respectively. These data suggested that TsIR-1316-LBD and TsIR-4810-LBD are promising vaccine candidates or novel drug targets against swine cysticercosis.

In vitro nitazoxanide exposure affects energetic metabolism of Taenia crassiceps

Nitazoxanide (NTZ) is a broad-spectrum drug used in intestinal infections, but still poorly explored in the treatment of parasitic tissular infections. This study aimed to evaluate the in vitro responses of the energetic metabolism of T. crassiceps cysticerci induced by NTZ. The organic acids of the tricarboxylic acid cycle, products derived from fatty acids oxidation and protein catabolism were analyzed. These acids were quantified after 24 h of in vitro exposure to different NTZ concentrations. A positive control group was performed with albendazole sulfoxide (ABZSO). The significant alterations in citrate, fumarate and malate concentrations showed the NTZ influence in the tricarboxylic acid (TCA) cycle. The non-detection of acetate confirmed that the main mode of action of NTZ is effective against T. crassiceps cysticerci. The statistical differences in fumarate, urea and beta-hydroxybutyrate concentrations showed the NTZ effect on protein catabolism and fatty acid oxidation. Therefore, the main energetic pathways such as the TCA cycle, protein catabolism and fatty acids oxidation were altered after in vitro NTZ exposure. In conclusion, NTZ induced a significant metabolic stress in the parasite indicating that it may be used as an alternative therapeutic choice for cysticercosis treatment. The use of metabolic approaches to establish comparisons between anti parasitic drugs mode of actions is proposed.

Clinical features and efficacy of microsurgery for treatment of cerebral cysticercosis of the fourth ventricle: a report of 24 patients

To analyze the clinical characteristics of 24 patients with cysticercosis of the fourth ventricle, and to evaluate the therapeutic efficacy of microsurgery. The clinical data of 24 patients with cysticercosis of the fourth ventricle referred the Department of Neurosurgery of the Affiliated Hospital of Qinghai University from January 2000 to December 2018 were collected, and the clinical features, imaging characteristics, surgical methods, therapeutic efficacy and postoperative complications were analyzed. The 24 patients included 15 men and 9 women, and had a mean age of 43.5 years (range, 16 to 68 years). Preoperative imaging examinations showed obvious dilatation of bilateral lateral ventricles, the third ventricle and middle cerebral aqueduct, and spherical or cystic dilatation of the fourth ventricle. There were 18 cases positive for antibodies against cysticercus, and 3 of the 21 cases were egg positives. All 24 cases received microsurgery, including 8 cases via the median aperture approach, 7 cases via the median aperture-cerebellar vermis approach, and 9 cases via the transcerebellomedullary fissure approach. There were 17 cases with complete delivery of vesicles, 5 cases with vesicle rupture and 2 cases with extraction of cystic fluid followed by separation and removal of cystic wall. All cases had obvious retraction of the ventricular system and disappearance of intracranial hypertension following surgery. There were 19 cases (79.17%) with well recovery, and 5 cases (20.83%) with aggravation or development of cerebellar ataxia, which recovered following treatment for 1 to 2 weeks. The transcerebellomedullary fissure approach is a safe and lowly invasive approach for the treatment of cysticercosis of the fourth ventricle.

Analysis of Immune Responses in Mice Orally Immunized with Recombinant pMG36e-SP-TSOL18/Lactococcus lactis and pMG36e-TSOL18/Lactococcus lactis Vaccines of Taenia solium.

Cysticercosis is a cosmopolitan zoonotic parasitic disease infected by larval of Taenia solium (T. solium). Several drugs for the treatment of cysticercosis, such as praziquantel, albendazole, and mebendazole, have certain toxicity and side effects. Considering that there is no vaccine available, we studied a new vaccine for cysticercosis in this study. The complete TSOL18 gene and the optimized SP-TSOL18 gene fragments were obtained using PCR-based accurate synthesis method. The secretory and intracellular recombinant pMG36e-SP-TSOL18/Lactococcus lactis (L. lactis) and pMG36e-TSOL18/L. lactis vaccines of T. solium were prepared. Immune responses in mice orally immunized with these two recombinant L. lactis vaccines were analyzed by the determination of specific antibodies (IgG, IgG1, IgG2a, and sIgA) in serum, spleen lymphocyte proliferation, and cytokines (IL-2, IFN-γ, IL-4, and IL-10) in spleen lymphocyte culture supernatant. Our results showed that, after the first immunization, in these two recombinant L. lactis vaccine groups, the levels of serum specific IgG, IgG2a, and IgG1 increased on 14–56 d and reached the highest level on days 42, 42, and 28, respectively. The level of specific sIgA of intestinal mucosa also increased on 14–56 d and reached the highest level on day 42. The level of spleen lymphocyte proliferation increased on 14–56 d and reached the highest level on day 42. The levels of IL-2, IFN-γ, IL-4, and IL-10 in spleen lymphocyte culture supernatant increased on 14–56 d and reached the highest level on days 42, 42, 28, and 28, respectively. These results indicated that the recombinant pMG36e-SP-TSOL18/L. lactis and pMG36e-TSOL18/L. lactis vaccines can induce specific cellular, humoral, and mucosal immune responses in mice with oral vaccination. More importantly, the recombinant pMG36e-SP-TSOL18/L. lactis vaccine has a better immune effect. In summary, these results demonstrated the possibility of using L. lactis strain as a vector to deliver protective antigens of T. solium.

Unusual cases of Taenia crassiceps cysticercosis in naturally infected animals in the Czech Republic

The tapeworm Taenia crassiceps has an indirect life cycle. Occasionally, metacestode stages have been reported from aberrant hosts as dogs, cats, lemurs and humans. This study describes an unusual series of serious cysticercosis cases: an 18-month-old male Yorkshire terrier dog with pleural cysticercosis accompanied by a cough, a 10-year-old male Shih Tzu dog with subcutaneous cysticercosis as well as a Cape ground squirrel and a Senegal bushbaby, both with generalised cysticercosis. Surgery was successful only in the Shih Tzu. The Yorkshire terrier died a few hours after surgery, while the Cape ground squirrel was euthanised and the Senegal bushbaby died before surgery. Cysticerci from the four cases were identified morphologically and using molecular methods. Fragments of genes coding for cytochrome oxidase subunit 1 were sequenced for each of the four isolates. Their affiliation to T. crassiceps was confirmed by comparison with the sequence data of other isolates available in the GenBank database. In general, the comparison of sequences of all isolates showed low variability in nucleotide composition (at most five positions). The cases from captive zoo animals represent the first findings of T. crassiceps in the Cape ground squirrel and Senegal bushbaby. The optimal treatment of cysticercosis caused by T. crassiceps remains unclear. Successful attempts usually include extensive surgical interventions and prolonged anthelmintic treatment. Chemotherapeutic options are limited. Although regular deworming targeting intestinal helminths of dogs is not effective against T. crassiceps cysticerci, it may help to prevent contamination of the environment by tapeworm eggs contained in dog faeces and reduce the risk of infection for susceptible animals and humans.

In vivo treatment with nitazoxanide induces anaerobic metabolism in experimental intraperitoneal cysticercosis.

Taenia crassiceps cysticerci are used as experimental model to study the host-parasite relationship and treatment of cysticercosis. One of the described mode of actions of nitazoxanide (NTZ) is to block the pyruvate ferredoxine oxidoreductase (PFOR) enzyme which is an essential enzyme to the parasite metabolism. The aim of this study was to determine the in vivo influence of one dosage of NTZ on the energetic metabolism of T. crassiceps cysticerci. Thirty days after the intraperitoneal inoculation of T. crassiceps cysticerci, BALB/c mice were orally treated with 7.5mg/kg of NTZ. The control group was treated with physiologic solution (NaCl 0.9%). After 24h, the animals were euthanized and the cysticerci were removed, washed, and processed for biochemical analysis. The organic acids detection occurred through high-performance liquid chromatographic and spectrophotometric analysis. While there was no difference in the glucose dosages, it was possible to observe a significant increase in the lactate concentrations and a decrease in the pyruvate concentrations of the NTZ-treated groups when compared to the control group. Also, there was a decrease in the urea and alpha-ketoglutarate concentrations. This probably occurred due to the impairment of the parasite's PFOR and nitroreductases leading an impairment of the mitochondrial aerobic pathways. In conclusion, the in vivo NTZ treatment leads to an increase in the lactic fermentation and to a decrease in the protein catabolism in T. crassiceps cysticerci.

MicroRNA analysis of Taenia crassiceps cysticerci under praziquantel treatment and genome-wide identification of Taenia solium miRNAs

MicroRNAs (miRNAs) are small non-coding RNAs that have emerged as important regulators of gene expression and perform critical functions in development and disease. In spite of the increased interest in miRNAs from helminth parasites, no information is available on miRNAs from Taenia solium, the causative agent of cysticercosis, a neglected disease affecting millions of people worldwide. Here we performed a comprehensive analysis of miRNAs from Taenia crassiceps, a laboratory model for T. solium studies, and identified miRNAs in the T. solium genome. Moreover, we analysed the effect of praziquantel, one of the two main drugs used for cysticercosis treatment, on the miRNA expression profile of T. crassiceps cysticerci. Using small RNA-seq and two independent algorithms for miRNA prediction, as well as northern blot validation, we found transcriptional evidence of 39 miRNA loci in T. crassiceps. Since miRNAs were mapped to the T. solium genome, these miRNAs are considered common to both parasites. The miRNA expression profile of T. crassiceps was biased to the same set of highly expressed miRNAs reported in other cestodes. We found a significant altered expression of miR-7b under praziquantel treatment. In addition, we searched for miRNAs predicted to target genes related to drug response. We performed a detailed target prediction for miR-7b and found genes related to drug action. We report an initial approach to study the effect of sub-lethal drug treatment on miRNA expression in a cestode parasite, which provides a platform for further studies of miRNA involvement in drug effects. The results of our work could be applied to drug development and provide basic knowledge of cysticercosis and other neglected helminth infections.

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.

Successful Antiparasitic Treatment for Cysticercosis is Associated with a Fast and Marked Reduction of Circulating Antigen Levels in a Naturally Infected Pig Model

Taenia solium cysticercosis is a common parasitic infection of humans and pigs. We evaluated the posttreatment evolution of circulating parasite-specific antigen titers in 693 consecutive blood samples from 50 naturally infected cysticercotic pigs, which received different regimes of antiparasitic drugs (N = 39, 7 groups), prednisone (N = 5), or controls (N = 6). Samples were collected from baseline to week 10 after treatment, when pigs were euthanized and carefully dissected at necropsy. Antigen levels decreased proportionally to the efficacy of treatment and correlated with the remaining viable cysts at necropsy (Pearson's p = 0.67, P = 0.000). A decrease of 5 times in antigen levels (logarithmic scale) compared with baseline was found in 20/26 pigs free of cysts at necropsy, compared with 1/24 of those who had persisting viable cysts (odds ratio [OR] = 76.7, 95% confidence interval [CI] = 8.1-3308.6, P < 0.001). Antigen monitoring reflects the course of infection in the pig. If a similar correlation exists in infected humans, this assay may provide a minimally invasive and easy monitoring assay to assess disease evolution and efficacy of antiparasitic treatment in human neurocysticercosis.

Enhanced steroid dosing reduces seizures during antiparasitic treatment for cysticercosis and early after.

Neurocysticercosis (NCC) is a major cause of seizures and epilepsy in endemic countries. Antiparasitic treatment of brain cysts leads to seizures due to the host's inflammatory reaction, requiring concomitant steroids. We hypothesized that increased steroid dosing will reduce treatment-associated seizures. Open-label randomized trial comparing 6 mg/day dexamethasone for 10 days (conventional) with 8 mg/day for 28 days followed by a 2-week taper (enhanced) in patients with NCC receiving albendazole. Follow-up included active seizure surveillance and brain imaging. Study outcomes were seizure days and patients with seizures, both measured in days 11-42. Additional analyses compared days 1-10, 11-21, 22-32, 33-42, 43-60, and 61-180. Thirty-two individuals were randomized into each study arm; two did not complete follow-up. From days 11 to 42, 59 partial and 6 generalized seizure days occurred in 20 individuals, nonsignificantly fewer in the enhanced arm (12 vs. 49, p = 0.114). The numbers of patients with seizures in this period showed similar nonsignificant differences. In the enhanced steroid arm there were significantly fewer days and individuals with seizures during antiparasitic treatment (days 1-10: 4 vs. 17, p = 0.004, and 1 vs. 10, p = 0.003, number needed to treat [NNT] 4.6, relative risk [RR] 0.1013, 95% confidence interval [CI] 0.01-0.74) and early after dexamethasone cessation (days 11-21: 6 vs. 27, p = 0.014, and 4 vs. 12, p = 0.021, NNT 4.0, RR 0.33, 95% CI 0.12-0.92) but not after day 21. There were no significant differences in antiparasitic efficacy or relevant adverse events. Increased dexamethasone dosing results in fewer seizures for the first 21 days during and early after antiparasitic treatment for viable parenchymal NCC but not during the first 11-42 days, which was the primary predetermined time of analysis.

Current status of taeniasis and cysticercosis in Vietnam.

Several reports on taeniasis and cysticercosis in Vietnam show that they are distributed in over 50 of 63 provinces. In some endemic areas, the prevalence of taeniasis was 0.2-12.0% and that of cysticercosis was 1.0-7.2%. The major symptoms of taeniasis included fidgeted anus, proglottids moving out of the anus, and proglottids in the feces. Clinical manifestations of cysticercosis in humans included subcutaneous nodules, epileptic seizures, severe headach, impaired vision, and memory loss. The species identification of Taenia in Vietnam included Taenia asiatica, Taenia saginata, and Taenia solium based on combined morphology and molecular methods. Only T. solium caused cysticercosis in humans. Praziquantel was chosen for treatment of taeniasis and albendazole for treatment of cysticercosis. The infection rate of cysticercus cellulosae in pigs was 0.04% at Hanoi slaughterhouses, 0.03-0.31% at provincial slaughterhouses in the north, and 0.9% in provincial slaughterhouses in the southern region of Vietnam. The infection rate of cysticercus bovis in cattle was 0.03-2.17% at Hanoi slaughterhouses. Risk factors investigated with regard to transmission of Taenia suggested that consumption of raw meat (eating raw meat 4.5-74.3%), inadequate or absent meat inspection and control, poor sanitation in some endemic areas, and use of untreated human waste as a fertilizer for crops may play important roles in Vietnam, although this remains to be validated.