Concordance between two monoclonal antibody-based antigen detection enzyme-linked immunosorbent assays for measuring cysticercal antigen levels in sera from pigs experimentally infected with Taenia solium and Taenia hydatigena.

BACKGROUND: Antigen detection in Taenia solium cysticercosis confirms viable infection in the intermediate host (either pig or human). The reference B158/B60 monoclonal antibody (mAb)-based Ag-enzyme-linked immunosorbent assay (ELISA) has acceptable levels of sensitivity and specificity in human neurocysticercosis with multiple brain cysts, although its sensitivity is lower in cases with single brain cysts, whereas in porcine cysticercosis the assay specificity is affected by its frequent cross-reaction with Taenia hydatigena, another common cestode found in pigs. Our group has produced 21 anti-T. solium mAbs reacting against antigens of the whole cyst, vesicular fluid, and secretory/excretory products, identifying TsW8/TsW5 as the most promising pair of mAbs for an Ag-ELISA. METHODS: We report the use of the TsW8/TsW5 Ag-ELISA to measure cysticercus antigen levels [expressed as optical density (OD) values] in two panels of sera collected from day 0 (baseline) to day 90 postinfection (PI) from pigs experimentally infected with T. solium (n = 26) and T. hydatigena (n = 12). At baseline and on days 28 and 90 PI, we used Bland-Altman (BA) analysis and Lin's concordance correlation coefficients (CCC) to determine the concordance between the TsW8/TsW5 and the B158/B60 Ag-ELISA. RESULTS: The TsW8/TsW5 Ag-ELISA was able to efficiently measure circulating antigen levels in T. solium-infected pigs, similar to that obtained with the B158/B60 Ag-ELISA. Almost all paired log-OD differences between assays were within the limits of agreement (LoA) in the BA analysis at baseline and on days 28 and 90 PI (92.3%, 100%, and 100%, respectively), and a high concordance of log-ODs between assays was also found (Lin's CCC: 0.69, 0.92, and 0.96, respectively, all P < 0.001). In pigs infected with T. hydatigena, almost all paired log-OD differences were within the LoA in the BA analysis, whereas the concordance of log-ODs between assays was low at baseline (Lin's CCC: 0.24) but increased on days 28 and 90 PI (Lins' CCC: 0.88 and 0.98, P < 0.001). CONCLUSIONS/SIGNIFICANCE: The TsW8/TsW5 Ag-ELISA recognizes antigens in pigs with T. solium cysticercosis and is highly concordant with the B158/B60 Ag-ELISA. However, its diagnostic use is hampered by cross-reactions with T. hydatigena, as in other mAb-based Ag-ELISAs.

Using the model cestode Taenia crassiceps for the study of cysticercosis.

Taenia solium is the aetiological agent of taeniasis/cysticercosis, one of the most severe neglected tropical diseases (NTD) according to the World Health Organization (WHO). The life cycle of T. solium alternates between pigs (intermediate host) and humans (definitive host). In addition, humans can act as accidental intermediate hosts if they ingest infective eggs. In this case, the most severe condition of the disease occurs when parasites invade the central nervous system, causing neurocysticercosis (NCC). The complexity of the life cycle of T. solium imposes a barrier to study this pathogen thoroughly. Thus, related species, such as T. crassiceps are commonly used. Due to its capacity to multiply asexually, T. crassiceps can be maintained by serial passage in laboratory mice in standard biosecurity level facilities. In addition, an in vitro system to generate cysticerci in the presence of feeder cells has been recently developed. Despite model species display biological differences with their zoonotic counterparts, they have historically helped to understand the biology of the related pathogenic species and hence, generate improvements in NTD detection and control. In this chapter, we describe the procedures to carry out both in vivo and in vitro systems for T. crassiceps in the laboratory.

Sympatric occurrence of Taenia saginata and Sarcocystis spp. in cattle from Narok County, Kenya: meat inspection findings with molecular validation.

The epidemiological picture of Taenia saginata infections in Kenya is fragmented with limited available data. Although Sarcocystis species are significant meat-borne parasites, few studies have explored their occurrence in Kenya. This study aimed to estimate the occurrence of bovine cysticercosis and screen for the presence of Sarcocystis spp. A meat inspection-based survey was conducted in ten abattoirs in Narok County, Kenya, and inspection for T. saginata cysticerci was limited to the Triceps brachii muscle. The apparent occurrence of the parasite was 5.4% (95% CI, 3.8, 7.6, n=573). Molecular confirmation of T. saginata was done via nested polymerase chain reaction targeting the mitochondrial 12S ribosomal RNA gene and restricted fragment length polymorphism. Sarcocystis species were identified using a multiplex polymerase chain reaction method targeting the 18S ribosomal RNA gene sequences and the mitochondrial cytochrome c oxidase subunit I gene. Of the 31 cystic lesions tested, 26/31 (83.9%) were confirmed to be T. saginata.Sarcocystis cruzi and S. hominis were detected in 8/31 (25.8%) and 1/31 (3.2%) of the cystic lesions, respectively. Co-infections of S. cruzi and T. saginata were found in 6/31 lesions (19.4%). The confirmation of bovine cysticercosis and S. hominis is suggestive of the presence of risky culinary and sanitation practices that facilitate transmission. This is the first report and molecular confirmation of Sarcocystis spp. in cattle in the country. The presence of both zoonotic S. hominis and pathogenic S. cruzi highlights an underexplored concern of veterinary and human health significance, warranting further epidemiological investigation.

Epidemiology of swine cysticercosis in two rural communities of Zacapa, Guatemala.

Taeniasis/cysticercosis complex caused by Taenia solium, is a serious public health problem and causes major economic losses to swine producers in developing countries in Asia, Africa and the Americas. Despite scarce epidemiological data, Guatemala is considered endemic for T. solium. A cross-sectional study was conducted in Azacualpa and Malpais, two villages in the department of Zacapa, to assess the prevalence of swine cysticercosis and associated factors. Between March and October 2019, 149 pigs were examined by tongue palpation and serum samples were then collected to detect antibodies by ab-ELISA, and necropsy was performed on pigs that were positive by tongue palpation and/or ab-ELISA, to assess parasite load. Pig owners were asked to fill out a questionnaire on factors related to pig husbandry and occurrence of swine cysticercosis. Pearson's chi-square test and multivariate analysis were used to measure the association between serological results and other variables (p < 0.05 was considered significant). The seroprevalence of swine cysticercosis was 13.4% (13/97, 95% C.I. 6.6%-20.2%) and 25% (13/52, 95% C.I. 13.2%-36.8%) in Azacualpa and Malpais, respectively, yielding an overall seroprevalence of 17.4% (26/149, 95% C.I. 11.4%-23.5%). Parasite loads ranged from 1 to over 23,000 metacestodes per carcass. No bivariate association was found between exposure variables and seropositivity. A positive diagnosis by tongue palpation increased the odds of finding pigs seropositive for cysticercosis by a factor of 16.1 in the multivariate analysis. Despite the high prevalence and parasite load of T. solium, risk factors associated with cysticercosis were not significant in this study.

Nexus between prevalence of Taenia solium (Cysticercus cellulosae) in pigs and retrospective study of humans cysticercosis cases in Benin hospitals.

The cysticercosis is a major zoonotic disease in many developing countries. This study was carried out to determine the prevalence of porcine cysticercosis and to identify potential risk factors associated and their seroprevalence as well in Benin. The tongue palpation was performed on 4150 pigs from the pig farmers were randomly selected to diagnose cysticercosis and to assess the risk factors associated. In slaughterhouses, 792 pigs were inspected. Serum samples from 460 pigs were tested of the presence of Taenia solium cysticercosis using the HP10 antigen-ELISA (Ag-ELISA). A logistic regression model with a 95% confidence interval was used to analyse the main risk factors associated. The tongue palpation revealed a prevalence of 4.79% at the level of slaughterhouses versus 7.82% in the post-mortem inspection. The Ag-ELISA revealed that more than 40% of the pigs were positive. The risk factors identified were the origin area of pigs, the history of cysticercosis in the farms, the presence or absence of a latrine, the pig-farming systems, the age class of pigs and the source of watering. In addition, 34.48% individuals was tested for taenia versus 13.79% for cysticercosis in the hospitals surveyed. Our results showed the major revelation of porcine cysticercosis and its very high level of risk for a public health in all departments of Benin. Therefore, this study suggests the need to continue epidemiological and sociological surveys with a "One Health" approach in order to design and implement effective control measures in this country of high consumption of pigs.

A rare case of Cysticercus tenuicollis infection in a neonate lamb: Evidence of prenatal transmission.

Cysticercosis develops in lambs following a Cysticercus tenuicollis infestation, which is the larval stage of Taenia hydatigena. A 7-day-old lamb was examined for depression, anorexia, fever (40.5°C), congested mucus membranes, reluctance to move, and a hunched back. Upon necropsy, congestion was noted in the intestines and brain, and the heart had a loose consistency. Soft and pulpy kidneys were evident coupled with watery intestinal contents. Epsilon toxin (Clostridium perfringens type D toxin) was detected using enzyme-linked immunosorbent assay. A transparent cystic structure was incidentally found attached to the pancreas, within which a scolex was well demonstrated upon histopathology. Chronic active peritonitis was diagnosed at the cyst attachment site. C. tenuicollis was confirmed by polymerase chain reaction and genome sequencing. This report describes prenatal transmission of C. tenuicollis in the present lamb, although this condition is quite rare.

Spatial transferability of an agent-based model to simulate Taenia solium control interventions.

BACKGROUND: Models can be used to study and predict the impact of interventions aimed at controlling the spread of infectious agents, such as Taenia solium, a zoonotic parasite whose larval stage causes epilepsy and economic loss in many rural areas of the developing nations. To enhance the credibility of model estimates, calibration against observed data is necessary. However, this process may lead to a paradoxical dependence of model parameters on location-specific data, thus limiting the model's geographic transferability. METHODS: In this study, we adopted a non-local model calibration approach to assess whether it can improve the spatial transferability of CystiAgent, our agent-based model of local-scale T. solium transmission. The calibration dataset for CystiAgent consisted of cross-sectional data on human taeniasis, pig cysticercosis and pig serology collected in eight villages in Northwest Peru. After calibration, the model was transferred to a second group of 21 destination villages in the same area without recalibrating its parameters. Model outputs were compared to pig serology data collected over a period of 2 years in the destination villages during a trial of T. solium control interventions, based on mass and spatially targeted human and pig treatments. RESULTS: Considering the uncertainties associated with empirical data, the model produced simulated pre-intervention pig seroprevalences that were successfully validated against data collected in 81% of destination villages. Furthermore, the model outputs were able to reproduce validated pig seroincidence values in 76% of destination villages when compared to the data obtained after the interventions. The results demonstrate that the CystiAgent model, when calibrated using a non-local approach, can be successfully transferred without requiring additional calibration. CONCLUSIONS: This feature allows the model to simulate both baseline pre-intervention transmission conditions and the outcomes of control interventions across villages that form geographically homogeneous regions, providing a basis for developing large-scale models representing T. solium transmission at a regional level.

Bovine cysticercosis epidemiology and the economic impact of the triceps brachii incision in a South African export abattoir.

Taenia saginata is a zoonotic tapeworm of humans with bovines as its intermediate host (bovine cysticercosis). Traditional meat inspection is the main measure to identify the larval stage in carcasses and prevent human infection, but has a notoriously low sensitivity, especially in low prevalence settings. The legislation in multiple African countries mandates an incision in both triceps brachii muscles to detect the parasite as part of the normal post-mortem inspection, but this has an economic cost and is not universally mandated in other countries. The primary aim of this study was to investigate the epidemiology of bovine cysticercosis at an export abattoir in South Africa and determine the validity and cost of the triceps incision. Risk factors were investigated, and the effect of additional heart incisions on the current inspection. Four incisions were made into the heart in addition to the normal post-mortem inspection in 3353 carcasses. The proportion of positive animals with and without the cardiac and triceps incisions were compared using McNemar's chi-square tests, while risk factors were assessed using binary logistic regression. The economic impact of the triceps incision was estimated using a stochastic economic cost model. Thirty-three positive carcasses were identified for an apparent prevalence of 0.98 % (95 %CI, 0.69-1.36 %), while the true prevalence was estimated at 6.6 % (95 %CI, 4.3-8.8 %). All cysts were confirmed as T. saginata on histopathology with 70 % (95 %CI, 53-83 %) located in the heart. The additional cardiac incisions resulted in the detection of significantly more cases compared to the normal inspection method prevalence of 0.72 % (95 %CI, 0.47-1.05 %; P < 0.001). The apparent prevalence of T. saginata when omitting the triceps incision was not significantly lower compared to the prevalence when included in the inspection (P = 0.480). External feedlots (OR= 4.17, 95 %CI: 2.04-8.54, P < 0.001) and older animals (OR=3.90, 95 %CI: 1.17-13.03, P = 0.027) were associated with a positive detection. The current median annual financial cost to the food business operator from the triceps incision was estimated at $30387 (95 %CI: $0-$130696), with the proportion of deboned meat exported identified as the most important factor affecting cost (Spearman's rho=0.853). The identification of risk factors could aid in the development of a more effective risk-based inspection system. The current inspection should be modified to increase exposure of the heart and remove the triceps incisions. The latter should especially be considered given the minimal contribution to cysticercosis detection, the unsupported requirement for its inclusion specifically in Africa, and its economic impact, especially as beef exports increase.

Acute coenurosis in lambs.

Six 100-day-old mixed-breed lambs were examined in a farm with a semi-intensive system due to neurologic signs. Cachexia, bilateral blindness, stupor, severe drowsiness and lethargy with left and right movements of the head and neck were recorded after awakening and stimulation. Lambs died 10 days after the onset of the clinical signs. The lambs were necropsied, and after routine parasitology, bacteriology and histopathology, the occurrence of acute coenurosis was confirmed due to finding multiple cystic structures in the brain tissue. All lambs of the herd were treated with albendazole (orally, 25 mg/kg, two doses with an interval of 14 days). All shepherd dogs were treated with popantel (orally, one tablet/10 kg, two doses with an interval of 14 days). The affected lambs died despite this treatment. No new case of the disease was observed after the initiation of control measures. The present study shows the importance of preventive measure against coenurosis in a semi-intensive sheep farming system that includes implementing consistent parasite control programme in dogs being in contact with sheep.

Knowledge, attitudes and practices regarding porcine cysticercosis control among smallholder pig farmers in Kongwa and Songwe districts, Tanzania: A cross-sectional study.

Taenia solium taeniasis/cysticercosis (TSTC) is a parasitic zoonotic disease that is endemic in several developing countries, causing serious public health and economic impacts. A cross-sectional study was conducted to assess knowledge, attitudes and practices (KAP) related to porcine cysticercosis (PCC) transmission, prevention and control among smallholder pig farmers in Kongwa and Songwe Districts in Tanzania. A semi-structured questionnaire was administered to 692 smallholder pig farmers from randomly selected households. STATA software version 17 was used to analyse quantitative data, summarize farmers' KAP about PCC and calculate performance scores. Nearly half (42%) of the respondents had little knowledge regarding PCC, only 17% of the respondents had good practices towards prevention/control of PCC and 72% had a positive attitude towards PCC- prevention/control measures. The majority (73%) of smallholder pig farmers admitted deworming their pigs regularly, whereas 76% reported deworming themselves and their family members regularly. Albendazole and ivermectin are the most commonly used medications for deworming people and pigs, respectively. According to the findings, the majority of smallholder pig farmers in Kongwa and Songwe Districts showed a good attitude towards PCC prevention/control measures but had limited knowledge of the PCC life cycle and control. In addition, only one in five farmers was engaged in good practices. The findings revealed further that farmers are engaged in risky behaviours that aid the spread and perpetuation of the T. solium parasite in the study area. It is recommended that farmers should be given proper health education on the T. solium transmission cycle and preventive/control practices to limit PCC transmission.

Confirmation by necropsy of a high prevalence of porcine cysticercosis in a rural district of Madagascar.

Neurocysticercosis is recognized as an important health issue in the Malagasy population. To date, investigations into prevalence of infection with the causative agent, Taenia solium, in the parasite's natural animal intermediate hosts, have relied on serological methods which have been found to be non-specific. We determined the prevalence of porcine cysticercosis among pigs from a contiguous area of the Betafo and Mandoto administrative districts, Vakinankaratra Region, Madagascar. One hundred and four slaughter-weight pigs were examined by detailed necropsy examination including slicing of the heart, tongue, masseter muscles, diaphragm and carcase musculature. Thirty-seven animals (35.6%) were found infected with T. solium, representing one of the highest rates of infection ever reported, worldwide. These findings highlight the importance of T. solium in Madagascar and support the need for increased efforts to prevent the parasite's transmission to reduce its burden on the health of the Malagasy population.

Cysticercosis in free-ranging agoutis (Dasyprocta leporina) in the Eastern Brazilian Amazon.

The study describes the occurrence of cysticercosis in liver of 22 wild agoutis (Dasyprocta leporina) in the Brazilian Amazon. The phylogenetic analysis and microscopic characteristics of metacestodes in liver tissue sections, associated with the geographic distribution of the intermediate hosts indicated that a possibly novel Taenia sp. metacestode caused the parasitism. Additionally, two cases of hepatic co-infection by Taenia sp., Calodium sp. and Echinococcus oligarthra were also observed among the analyzed animals. The results point to the need for a better understanding of hepatotropic parasites among wild rodents in the Brazilian Amazon.

Acute cysticercosis caused by Cysticercus tenuicollis in lambs.

Twelve 30- to 75-day-old mixed breed lambs were examined in an intensive system because of sudden recumbency and death. Clinical examination revealed sudden recumbency, visceral pain, and auscultation of respiratory crackles. Lambs died shortly (between 30 minutes and 3 hours) after the onset of clinical signs. The lambs were necropsied, and after routine parasitology, bacteriology and histopathology procedures, the occurrence of acute cysticercosis caused by Cysticercus tenuicollis was confirmed. The use of the suspect infested feed (newly purchased starter concentrate) was discontinued and other lambs of the flock were treated with praziquantel (15 mg/kg, single dose, orally). After these actions, no new cases were observed. The present study showed the importance of preventive measures against cysticercosis in intensive sheep farming systems which include proper storage of feed, preventing feed and environmental access by potential definitive hosts, and implementing consistent parasite control programs in dogs that are in contact with sheep.

Subcutaneous Taenia crassiceps Cysticercosis in a Ring-Tailed Lemur (Lemur catta) in a Serbian Zoo.

BACKGROUND: Different rodent species serve as natural intermediate hosts for carnivore tapeworm Taenia crassiceps. However, this cestode occasionally infects various dead-end hosts including humans and other primates and may cause serious pathological implications with potentially fatal outcome. In this paper, we present subcutaneous cysticercosis caused by T. crassiceps, found in a previously healthy 17-years-old male ring-tailed lemur (Lemur catta) in a Serbian Zoo. CASE PRESENTATION: The animal was presented to a veterinarian with a history of periarticular subcutaneous swelling in medial right knee region. After fine needle aspiration revealed cycticerci-like structures, a surgery was performed for complete extraction of the incapsulated multicystic mass containing numerous cysticerci. Collected material was sent for parasitological, histological and molecular analysis. One month after surgery, the lemur died due to respiratory failure unrelated to cysticercosis. Based on morphological features of large and small hooks and characteristic proliferation of cysticerci, a metacestode of T. crassiceps was identified, which was confirmed after sequencing of obtained amplicons and comparing them to the GenBank database. CONCLUSIONS: This is one of the few reported cases of T. crassiceps cysticercosis in a ring-tailed lemur, and the first one in Serbia. This endangered species seem to be more sensitive for T. crassiceps than other non-human primates, which represents serious conservation challenge for captive animals. Due to zoonotic nature of the parasite, challenging diagnosis, severity of the disease, difficult treatment and possible fatalities, high biosecurity measures are of particular importance, especially in endemic regions.

An epidemiological survey of porcine cysticercosis in Rungwe District, Tanzania.

Taeniasis/cysticercosis caused by tapeworms belonging to the genus Taenia, poses serious veterinary and public health problems, resulting in economic burden in endemic low-income countries worldwide. However, little epidemiological data exist on infection status among pigs in many areas in Tanzania. We conducted a cross-sectional survey in Rungwe District, Mbeya Region, Tanzania, to define the prevalence and risk factors associated with porcine cysticercosis transmission. One-hundred sixty-nine pigs from 152 households were examined for circulating taeniid antigens by cysticercosis antigen (Ag) enzyme-linked immunosorbent assay (ELISA). Agarose gel electrophoresis was used to differentially diagnose Taenia species-specific cysticerci DNA bands. Structured questionnaires were administered in the surveyed households to collect information on risk factors for porcine cysticercosis transmission. Sera from eleven household pigs tested positive for porcine cysticercosis in the Ag-ELISA with an apparent prevalence of 6.5 % (95 % C.I. 3.8-11.3 %) and estimated true prevalence of 6.1 % (95 % C.I. 3.3-10.9 %). DNA Gel electrophoresis confirmed that 100 % of cysticerci isolated amongst pigs slaughtered in the study area belonged to T. solium. Of the five surveyed wards, positive household pigs were from Bulyaga, Kiwira, and Mpuguso. Lack of knowledge on porcine cysticercosis among household members was found to be significantly associated with positivity of Taenia species antigen in pigs sera (OR = 7.742, p = 0.017). Our results show that porcine cysticercosis is prevalent in Rungwe. There is a definite need to establish control measures against this potential zoonosis to safeguard veterinary and public health in the Rungwe District.

Taenia solium: Socioeconomic changes and prevalence evolution in four endemic communities in northwestern Mexico.

In Mexico, for the past 30 years, a continuous decrease in the incidence of clinical taeniosis/cysticercosis has been documented. This work aimed to determine the influence of improvement in socioeconomic conditions on the prevalence of Taenia solium in four endemic communities in northwestern Mexico. This study was carried out in two phases. First, documentary information (1989-2018) was collected about the prevalence of Theridion solium in the federal entity of Sinaloa State. Second, a pilot study was performed in four communities of Sinaloa, which had an endemic history of Taenia transmission. In each community, a risk factor questionnaire was applied, and serum and stool samples were collected for convenience in a non-probabilistic way. Anti-cysticercus antibodies and adult worm coproantigen were determined. The documentary analysis showed the incidence of taeniosis and cysticercosis to have decreased by 98 and 53%, respectively, while the human development index increased by 5% (1992-2017). Our data suggest that the risk of parasitic transmission is low, although female sex was a risk factor for reporting tremors or seizures (prevalence rate 2.1336, CI: 1.1821-3.8508) and background of tapeworm infection (prevalence rate 1.2893, CI: 0.9795-1.6972). No tapeworms or eggs were found while examining stool samples, but protozoa cysts were observed in four samples. Unexpectedly, only one of the 79 stool samples was positive for coproantigens. This positive result was confirmed in a second sample. However, the evaluation of a third sample was negative. No antibodies were found in human (n = 377) or pig (n = 69) samples. These data suggest parasite transmission has been interrupted and could be possibly associated with improving socioeconomic conditions. Further studies are needed to determine the real prevalence of zoonoses in Mexico.

Assessing the burden of Taenia solium cysticercosis in Burundi, 2020.

BACKGROUND: Taenia solium cysticercosis is a zoonotic disease that is endemic in many low- and middle-income countries where risk factors for disease transmission are present. The economic impact of cysticercosis on public health and on the pig production sector is not well known in many of those countries, including Burundi. This study aimed at estimating the burden of T. solium cysticercosis in Burundi including data on humans and pigs. METHODS: Epidemiological and economic data were collected from literature up to July 30, 2021 and governmental and non-governmental agencies. Direct and indirect costs for neurocysticercosis (NCC)-associated epilepsy and losses due to porcine cysticercosis were estimated to assess the economic burden, while the health burden was estimated using zoonotic disability-adjusted life years (zDALYs). Different probability distributions (Uniform, Beta, Dirichlet and Gamma) were applied depending on the type of epidemiological parameter. Monte Carlo simulations and 100,000 iterations were used to calculate the 95% uncertainty interval (UI) for each parameter and perform sensitivity analyses. RESULTS: In Burundi, 4.26 million USD (95% UI, 1,858,308-8,190,951) were estimated as economic impact due to T. solium cysticercosis in humans and pigs, of which 40.2% (95% UI, 10.3-75.1) of the total costs were due to NCC-associated epilepsy and 59.8% (95% UI, 24.9-89.7) of the losses due to porcine cysticercosis. The cost per NCC-associated epilepsy case was 72 USD (95% UI, 25-168), representing 30.8% of the GDP per capita in 2020. The probable incident cases and deaths for NCC-associated epilepsy were 9065 (95% UI, 2370-16,716) and 61 (95% UI, 16-114), respectively. More than 2 zDALYs (95% UI, 1.1-3.4) per thousand person-years was estimated, of which an average of 1.3 DALYs [0;0] (95% UI, 0.3-2.6) was due to NCC- associated epilepsy and 0.8 animal loss equivalents (ALEs) (95% UI, 0.3-1.5) due to porcine cysticercosis. CONCLUSIONS: This study provides evidence of a significant burden of T. solium cysticercosis for Burundi's population. We urge policy makers to use these evidence-based results and put T. solium cysticercosis on the public health agenda of the country. This study recommends urgent action to find solutions for integrated control strategies for T. solium cysticercosis in Burundi.

The prevalence of Taenia spp. in pigs slaughtered in Kinshasa.

Taenia hydatigena is a non-zoonotic worm that has dogs and wild canids as definitive hosts. Its presence induces cross reactions in certain diagnostic tests for porcine cysticercosis caused by T. solium, the occurrence of which has a considerable public health and economic impact. In the Democratic Republic of the Congo (DR Congo), T. solium is considered endemic, however, the prevalence of T. hydatigena has not been estimated yet. The objective of the study was therefore to estimate the prevalence of T. hydatigena cysticercosis by serological and molecular diagnostic tools in pigs slaughtered in DR Congo. A total of 480 pigs slaughtered in 6 slaughter slabs in Kinshasa, DR Congo, were examined. The thoracal and abdominal cavity organs were inspected for cysts, which were analyzed using PCR-RFLP. Furthermore, 480 sera were collected, and analyzed for the presence of circulating Taenia spp. cysticercus antigens, using the B158/B60 Ag-ELISA. Upon inspection of the carcass, 41 cysts suspected to be metacestodes of Taenia spp. were collected, from the following viscera: spleen (24/41, 59%), liver (13/41, 32%), intestine (3/41, 7%) and lung (1/41, 2%). Molecular analyses revealed a T. hydatigena prevalence of 0.2% (95% CI: 0.0001-0.0116), based on a single lesion (1/480), taken from the spleen. Out of the 480 sera collected, the presence of circulating Taenia spp. cysticerci antigens was detected in 32 (6.7%; 95% CI: 4.5-11.2). The results of this study revealed that T. hydatigena is present in pigs sold in markets in the city of Kinshasa in DR Congo, albeit at a very low prevalence, thus the impact on the interpretation of the B158/B60 seems low in this setting. Detection of circulating antigens in porcine sera by Ag-ELISA, shows that pigs slaughtered in Kinshasa, DR Congo, were infected with viable cysticerci of Taenia spp. which in turn can infect humans.

In vitro system for the growth and asexual multiplication of Taenia crassiceps cysticerci.

Taenia solium is the aetiological agent of cysticercosis, a zoonosis that causes severe health and economic losses across Latin America, Africa and Asia. The most serious manifestation of the disease is neurocysticercosis, which occurs when the larval stage (cysticercus) establishes in the central nervous system. Using Taenia crassiceps as an experimental model organism for the study of cysticercosis, we aimed to identify the in vitro conditions necessary to allow parasite development at the short- and long terms. First, cysticerci were incubated for 15 days in different media and parasite densities. The number of buddings and cysticerci diameter were measured to evaluate asexual multiplication and parasite growth, respectively. Vitality was determined by trypan blue staining and morphology analysis. As a result, high cysticerci density and medium containing FBS and the excretion/secretion (E/S) products of feeder cells induced parasite survival, growth and multiplication. Then, the long-term (5 weeks) incubation of the parasites in co-culture with feeder cells was evaluated. Consequently, the mammalian cell lines induced a significant increase in total parasite volume while axenic cultures did not show any statistically significant change over time. In this study, the proper conditions to maintain T. crassiceps in vitro are described for the first time in a simpler and more controlled setting other than experimental infections. In addition, it was shown that cysticerci growth, survival and asexual multiplication depend on a complex network of secreted factors from both parasite and host.