Search

Background: Taenia solium neurocysticercosis (NCC) has been documented as one of the major causes of epilepsy in developing countries. However, methodological limitations have hindered the evaluation of the epidemiological relationship between cysticercosis and epilepsy at the community level.Methods: We used the WHO protocol for epidemiological evaluation of neurological disorders to conduct a door-to-door survey among 2723 residents of San Pablo del Lago, an Ecuadorean rural community in which T. solium taeniasis/cysticercosis was known to be endemic. The WHO protocol was complemented by neuroimaging and immunological tests to confirm the diagnosis of this infection.Results: In all 31 people suffering from active epilepsy were detected (prevalence 11.4 per 1000, 95% CI:7.7-15.4); 26 agreed to undergo a computer tomography (CT) examination, and 28 agreed to have blood drawn for serodiagnosis. Fourteen of the 26 (53.8%) had CT changes compatible with NCC and six of the 28 (21.4%) tested positive in the enzyme-linked immunoelectro-transfer blot (EITB) assay. In a seizure-free random sample of this population, 17 of 118 (144 per 1000) subjects examined by CT and 10 out of 96 (104 per 1000) examined by EITB had evidence of this infection. The differences between the epilepsy group and the random sample of the population were statistically significant (OR = 6.93, 95% CI: 2.7-17.5, P < 0.001) for CT diagnosis, but not for EITB results (OR = 2.75, 95% CI: 0.8-7.1, P > 0.12, NS).Conclusions: These findings confirm that T. solium NCC is a significant cause of epilepsy at the community level in Andean villages of Ecuador. It is important to initiate effective public health interventions to eliminate this infection, which may be responsible for at least half of the cases of reported epilepsy in Ecuador. [ABSTRACT FROM AUTHOR]

Background: In 1996 the seroprevalence of schistosomiasis in expatriates and travelers who had contact with Lake Malawi, a fresh water source thought to be schistosomiasis-free, was measured at 32%. Clinicians in Arusha, Tanzania, questioned the prevalence of Schistosoma infection in expatriates living in the Arusha region, and how schistosomiasis might relate to symptoms of chronic fatigue in Arusha expatriates.Method: We performed a cross-sectional survey of 80 expatriates living in the Arusha region of Tanzania to determine the seroprevalence of schistosome infection. Whole blood was analyzed by the Falcon assay screening test-enzyme-linked immunosorbent assay (FAST-ELISA) for the presence of species-specific Schistosoma mansoni and Schistosoma haematobium antibodies to microsomal antigens of adult Schistosoma worms, followed by confirmatory enzyme-linked immunoelectrotransfer blot (Western blot). Volunteers answered a questionnaire which included length of residence in Arusha, risk factors, symptoms, and previous diagnosis of schistosomiasis.Results: Of the 80 expatriates sampled, 8 (10%) were positive for schistosomiasis (6 to S. mansoni only, 1 to S. haematobium, 1 to both species). Significant risk factors, elicited by questionnaire, included longer residence in the Arusha region (p =.020), history of fatigue (p =.010) and myalgias (p =.047), and previous diagnosis of schistosomiasis by stool or urine ova (p =.0007).Conclusion: The lower seroprevalence of schistosomiasis in Arusha expatriates, compared with expatriates and travelers to Lake Malawi, suggests a regional variation of rate of schistosomiasis infection. Although a history of fatigue and myalgias was related to seropositivity, there is no strong evidence that schistosomiasis infection is the cause of chronic fatigue in Arusha expatriates. [ABSTRACT FROM AUTHOR]

The pork tapeworm, Taenia solium , is among the leading causes of preventable epilepsy in the world and is common in rural areas of developing countries where sanitation is limited and pigs have access to human feces. Prior studies in rural villages of Peru have observed clusters of T. solium cysticercosis among pigs that live near human tapeworm carriers. Such spatial analyses, however, have been limited by incomplete participation and substandard diagnostic tests. In this study, we evaluated the association between necropsy-confirmed cysticercosis in pigs and their distance to T. solium tapeworm carriers in six villages in northern Peru. A total of six (1.4%) tapeworm carriers were detected using copro-antigen enzyme-linked immunosorbent assay and seven of 10 (70%) pigs belonging to the tapeworm carriers were found with viable cyst infection on necropsy. This was significantly greater than the prevalence of viable cyst infection among pigs living < 500 m (11%) and > 500 m (0.5%) from a tapeworm carrier ( P < 0.001 for distance trend). Similar statistically significant prevalence gradients were observed after adjustment for possible confounders and for other pig-level outcomes including infection with > 10 viable cysts, degenerated cyst infection, and serological outcomes. This investigation confirms that porcine cysticercosis clusters strongly around tapeworm carriers in endemic rural regions of northern Peru and supports interventions that target these hotspots.

Background: The enzyme-linked immunoelectrotransfer blot (EITB) assay is the reference serological test for neurocysticercosis (NCC). A positive result on EITB does not always correlate with the presence of active infections in the central nervous system (CNS), and patients with a single viable brain cyst may be EITB negative. Nonetheless, EITB antibody banding patterns appears to be related with the expression of 3 protein families of Taenia solium, and in turn with the characteristics of NCC in the CNS (type, stage, and burden of viable cysts)., Methods: We evaluated EITB antibody banding patterns and brain imaging findings of 548 NCC cases. Similar banding patterns were grouped into homogeneous classes using latent class analysis. The association between classes and brain imaging findings was assessed., Results: Four classes were identified. Class 1 (patients negative or only positive to the GP50 band, related to the protein family of the same name) was associated with nonviable or single viable parenchymal cysticerci; class 2 (patients positive to bands GP42-39 and GP24, related to the T24-42 protein family, with or without anti-GP50 antibodies) was associated with intraparenchymal viable and nonviable infections; classes 3 and 4 (positive to GP50, GP42-39, and GP24 but also responding to low molecular weight bands GP21, GP18, GP14, and GP13, related to the 8 kDa protein family) were associated with extraparenchymal and intraparenchymal multiple viable cysticerci., Conclusions: EITB antibody banding patterns correlate with brain imaging findings and complement imaging information for the diagnosis of NCC and for staging NCC patients., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

The lentil lectin glycoprotein enzyme-linked immunoelectrotransfer blot (LLGP EITB, reported sensitivity 99% and specificity 100%) is used as a serologic marker of exposure to Taenia solium in pigs. However, only a limited number of parasites have been evaluated for cross reactivity. Pigs may host other related cestode infections, including Taenia hydatigena, which have not been formally evaluated for cross-reactions. We investigated a corral in Tumbes, Peru, a region where a cysticercosis elimination demonstration project was completed in 2012. In this corral, 14/19 (73.7%) 6-8-week-old piglets were reactive to GP50 on LLGP EITB, and all had circulating Taenia sp. antigens. From eight necropsied piglets; four were infected with T. hydatigena metacestodes whereas none had evidence of T. solium infection. Two resident dogs were subsequently confirmed to have T. hydatigena taeniasis. These results suggest GP50 cross-reactivity in T. hydatigena- infected pigs, although controlled experimental infection is needed to confirm this hypothesis.