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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 A comprehensive search was conducted for published and unpublished studies.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., Competing Interests: The authors have declared that no competing interests exist.

Background: In neurocysticercosis, the larval form of the pork tapeworm Taenia solium appears to evolve through three phases-active, degenerative and sometimes calcification-before disappearance. The antihelmintic drug, albendazole, has been shown to hasten the resolution of active cysts in neurocysticercosis. Little is known about the time cysts take to progress through each phase, with or without treatment., Methods: We reconfigured brain imaging data from patient level to cyst level for 117 patients in a randomized clinical trial of albendazole in which images were taken at baseline, 1, 6, 12 and 24 mo. Applying a multistate model, we modelled the hazard of a cyst evolving to subsequent cyst phases before the next imaging (vs no change). We examined the impact of albendazole treatment overall and by patient and cyst characteristics on the hazard., Results: Albendazole accelerated the evolution from the active to degenerative phase (HR=2.7, 95% CI 1.3 to 6.5) and from the degenerative phase to disappearance (HR=1.9, 95% CI 1.1 to 3.9). Albendazole's impact was stronger for patients who were male, did not have calcified cysts at baseline and who had multiple cysts in different locations., Conclusions: This research provides a better understanding of where in the cyst trajectory albendazole has the greatest impact., (© The Author(s) 2019. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: The efficacy of current antiparasitic treatment for cerebral Taenia solium cysticercosis with either albendazole (ABZ) or praziquantel (PZQ) is suboptimal. A recent study demonstrated that combining these 2 antiparasitic drugs improves antiparasitic efficacy. We present here the parasiticidal efficacy data obtained during a previous phase II pharmacokinetic study that compared combined ABZ plus PZQ with ABZ alone., Methods: The study was a randomized, double-blinded, placebo-controlled phase II evaluation of the pharmacokinetics of ABZ (15 mg/k/d, for 10 days) and PZQ (50 mg/k/d, for 10 days) in intraparenchymal brain cysticercosis. Patients received the usual concomitant medications, including an antiepileptic drug (phenytoin or carbamazepine), dexamethasone, and ranitidine. Randomization was stratified by antiepileptic drug. Patients underwent safety laboratory evaluations at days 4, 7, and 11, as well as magnetic resonance (MR) imaging at 6 months to assess parasiticidal efficacy., Results: Thirty-two patients were included, 16 in each arm. All of them completed antiparasitic treatment and underwent follow-up brain MR imaging. Cysticidal efficacy was strikingly higher in the combined ABZ-plus-PZQ group than in the ABZ-alone group (proportion of cysts resolved, 78 of 82 [95%] vs 23 of 77 [30%] [relative risk {RR}, 3.18; 95% confidence interval {CI}, 2.08-4.88; P < .001]; patients with complete cyst clearance, 12 of 16 [75%] vs 4 of 16 [25%] [RR, 3.00; 95% CI, 1.23-7.34; P = .005])., Conclusions: The combination of ABZ plus PZQ is more effective in destroying viable brain cysticercosis cysts than ABZ alone., Clinical Trials Registration: NCT00441285., (© The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.)

Background: Neurocysticercosis is a leading cause of seizures and epilepsy in most of the world, and it occurs when Taenia solium larval cysts infect the central nervous system. T. solium tapeworm infection is endemic in much of Peru, but there are scarce data on the prevalence in many rural highland communities where it is likely to be hyper-endemic. Peace Corps Volunteers live and work in these communities; however, to our knowledge, they have not been used to facilitate public health research., Materials and Methods: We utilized Peace Corps Volunteers to estimate the prevalence of T. solium tapeworm infection in seven rural communities in northern Peru. A convenience non-random sampling frame was used. Peace Corps Volunteers facilitated the collection of stool samples (N = 2,328), which were analyzed by sedimentation and microscopy. Niclosamide treatment and purgation preceded species identification, which was done by PCR-REA., Results: Taenia sp. egg-positive stool samples were found in three of the seven communities we surveyed. The overall prevalence of Taenia sp. egg positivity was 2.1% (49/2,328) (95% CI = 1.6-2.8%) with prevalence up to 4.3% (42/977) (95% CI = 3.1-5.8%) by community. All 34 of the specimens tested by PCR-REA were T. solium. The overall prevalence of T. solium tapeworm infection was 1.5% (34/2,328) (95% CI = 1.0-2.0%). Prevalence up to 2.9% (28/977) (95% CI = 1.9-4.1%) by community was observed., Conclusion/significance: This study recorded high T. solium tapeworm prevalence, and identified hyper-endemic rural communities. It demonstrates that synergy between researchers and Peace Corps Volunteers can be an effective means to conducting large-scale, community-based studies in remote areas of Peru.

Albendazole is an anthelmintic drug widely used in the treatment of neurocysticercosis (NCC), an infection of the brain with Taenia solium cysts. However, drug levels of its active metabolite, albendazole sulfoxide (ABZSO), are erratic, likely resulting in decreased efficacy and suboptimal cure rates in NCC. Racemic albendazole sulfoxide is composed of ABZSO (+)-(R)- and (-)-(S) enantiomers that have been shown to differ in pharmacokinetics and activity against other helminths. The antiparasitic activities of racemic ABZSO and its (+)-(R)- and (-)-(S) enantiomers against T. solium cysts were evaluated in vitro. Parasites were collected from naturally infected pigs, cultured, and exposed to the racemic mixture or to each enantiomer (range, 10 to 500 ng/ml) or to praziquantel as a reference drug. The activity of each compound against cysts was assayed by measuring the ability to evaginate and inhibition of alkaline phosphatase (AP) and parasite antigen release. (+)-(R)-ABZSO was significantly more active than (-)-(S)-ABZSO in suppressing the release of AP and antigen into the supernatant in a dose- and time-dependent manner, indicating that most of the activity of ABZSO resides in the (+)-(R) enantiomer. Use of this enantiomer alone may lead to increased efficacy and/or less toxicity compared to albendazole.

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.

Cysticercosis is a zoonotic disease of humans produced by the larval stage of swine parasite, Taenia solium. Chemotherapy of infected pigs is a possible strategy for avoiding disease transmission and improving health programs in endemic areas of cysticercosis. In this preliminary study, seven naturally infected pigs from 6 to 12 months of age were allotted to treated (n = 4) and control groups (n = 3). The treated animals received a subcutaneous injection in their forelegs and thighs of 15 mg/kg per body weight of albendazole sulphoxide (ABZSO; Pisa, Mexico) once per day for 8 days. At the same time, the control group received a subcutaneous injection of saline solution (9% NaCl). After 12 weeks, all the animals were slaughtered and at least 200 metacestodes were isolated from the muscles and brain of each animal. Using histology and the metacestode viability criteria described in this study, treated animals had no viable cysts in their muscle (0/200), while 7 of 17 (41.1%) viable cysts were observed in those isolated from their brains. In the control group, 183/200 (91.5%) muscle metacestodes were viable and from brain, 22/29 (75.8%) metacestodes were viable. The 15 mg/kg per body weight dosage of ABZSO was 100% effective against muscular cysticercosis as shown by the lack of viable cysts and the micro-calcifications in meat from the treated pigs., (Copyright 2002 Elsevier Science B.V.)