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The prevalence and characteristics of human taeniasis/cysticercosis and porcine cysticercosis were assessed in an endemic area of the Peruvian highlands. Individuals from 10 communities had stool examinations (N = 2,951) and serologic testing for Taenia solium antibodies (N = 2,583). The total porcine population present (N = 703) was also examined by serology. Cysticercosis is hyperendemic in this area and is associated with an important number of seizure cases. Human seroprevalence by village ranged from 7.1-26.9% (mean, 13.9%). Seroprevalence was higher among individuals with a history of seizures but not in those reporting a history of headache or intestinal taeniasis. Prevalence of taeniasis ranged from 0-6.7% (median, 2.5%). Coproantigen detection found 2.4 times more taeniasis cases than did microscopy (direct and after concentration). Age distribution for taeniasis showed a peak at younger ages than for seroprevalence. Porcine seroprevalence ranged from 42-75%. Random effects logistic regression models for human seropositivity demonstrated both in-house clustering of cases and a large increase in risk associated with a tapeworm carrier in the house. Besides confirming the close relationship between taeniasis and cysticercosis cases, this large-scale field study demonstrated early age of tapeworm and cysticercosis infections in humans, and short duration of taeniasis infections. more...

End stages of neurocysticercosis include residual intraparenchymal brain calcifications and hydrocephalus. Although brain calcifications alone have a benign prognosis, hydrocephalus is frequently associated with chronic inflammation and intracranial hypertension, together with a protracted clinical evolution, and may lead to patient deaths. By using a monoclonal-based antigen detection enzyme-linked immunosorbent assay, we measured the levels of circulating parasite antigen in the sera of 56 patients with neurocysticercosis: 27 with calcifications only and 29 with hydrocephalus. The assay gave positive results in 14 of 29 patients with hydrocephalus but was consistently negative in patients with calcifications. Circulating parasite antigen in hydrocephalus secondary to neurocysticercosis indicates the presence of live parasites in these patients and thus a potential benefit from antiparasitic therapy. more...

Cysticercosis, the infection by the larvae of Taenia solium, is a major cause of acquired epilepsy in the world; it also causes significant economic loss because of contaminated pork. This disease is endemic in most developing countries and no control strategy has yet been proven efficient and sustainable. To further evaluate the full potential of single-dose oxfendazole treatment for pigs as a control measure, 20 pigs with cysticercosis were treated with oxfendazole and later matched with 41 naive pigs and exposed to a natural challenge in a hyperendemic area. New infections were found by serologic testing in 15 of the 32 controls (47%), and by the presence of cysts at necropsy in 12 of them (37%). Only minute residual scars were detected in the carcasses of oxfendazole-treated pigs. Pigs with cysticercosis, once treated with oxfendazole, are protected from new infections for at least three months. more...

Human Taenia solium cysticercosis is a major cause of epilepsy in developing countries, and porcine infection causes widespread economic losses because of infested pork. Recently, the use of oxfendazole (OFZ) for porcine cysticercosis provided, for the first time, an effective, single-dose treatment. We performed a controlled study to determine the time required between treatment with a single dose of OFZ and the death of cysticerci to define its applicability as preslaughter treatment or as a field control measure. Twenty naturally infected pigs were included in this study. Sixteen received a single dose (30 mg/kg) of OFZ, and were killed in groups of four at one, two, four, and 12 weeks after treatment. Four untreated controls were killed at week 12. No adverse reactions to OFZ were noted. A clear decrease in viability and number of cysts was evident after the first week after therapy, but even at week 4 some viable cysticerci were found in all samples. Twelve weeks after treatment, all meat appeared clear and only minuscule scars remained, except in one animal that had viable brain cysts. This study confirms the efficacy of a single dose of 30 mg/kg of OFZ for porcine cysticercosis but demonstrates that preslaughter treatment of pigs with OFZ will not be useful in controlling cysticercosis. The inclusion of porcine treatment with OFZ in mass cysticercosis control programs is, however, highly promising because it is a simple, effective, inexpensive, and potentially sustainable method for decreasing the porcine reservoir of cysticercosis in disease-endemic countries. more...

The pig is a vital link in the transmission cycle of Taenia solium, the cestode responsible for human-porcine cysticercosis. Infected pigs also represent an important source of economic loss to farmers in developing countries. Past efforts to find an adequate therapeutic regimen to treat this parasite disease in swine have failed because of low efficacy, high cost, side effects, or the need for multiple doses. In this randomized, no treatment-controlled study, the efficacy and safety of oxfendazole and praziquantel for the treatment of porcine cysticercosis were evaluated in 16 naturally infected pigs. Four groups of four pigs were treated with oxfendazole, praziquantel, oxfendazole plus praziquantel, or untreated. The pigs were humanely killed 12 weeks post-treatment, the number of cyst was counted, and parasite viability was assessed by cyst evagination. No detectable side effects were seen in any of the pigs. Praziquantel treatment alone appeared to reduce the number of cysts, but did not decrease the viability of the remaining parasites. Treatment with oxfendazole alone or oxfendazole plus praziquantel killed all of the parasites, and left only microcalcifications in the meat. Oxfendazole provides, for the first time, a practical, effective, inexpensive, and single-dose therapy for porcine cysticercosis. more...