A qualitative assessment of the context and enabling environment for the control of Taenia solium infections in endemic settings.

BACKGROUND: Taenia solium (T. solium), is a zoonotic helminth causing three diseases namely; taeniasis (in humans), neurocysticercosis (NCC, in humans) and porcine cysticercosis (PCC, in pigs) and is one of the major foodborne diseases by burden. The success or failure of control options against this parasite in terms of reduced prevalence or incidence of the diseases may be attributed to the contextual factors which underpin the design, implementation, and evaluation of control programmes. METHODOLOGY/PRINCIPAL FINDINGS: The study used a mixed method approach combining systematic literature review (SLR) and key informant interviews (KII). The SLR focused on studies which implemented T. solium control programmes and was used to identify the contextual factors and enabling environment relevant to successful inception, planning and implementation of the interventions. The SLR used a protocol pre-registered at the International prospective register of systematic reviews (PROSPERO) number CRD42019138107 and followed PRISMA guidelines on reporting of SLR. To further highlight the importance and interlinkage of these contextual factors, KII were conducted with researchers/implementers of the studies included in the SLR. The SLR identified 41 publications that had considerations of the contextual factors. They were grouped into efficacy (10), effectiveness (28) and scale up or implementation (3) research studies. The identified contextual factors included epidemiological, socioeconomic, cultural, geographical and environmental, service and organizational, historical and financial factors. The enabling environment was mainly defined by policy and strategies supporting T. solium control. CONCLUSION/SIGNIFICANCE: Failure to consider the contextual factors operating in target study sites was shown to later present challenges in project implementation and evaluation that negatively affected expected outcomes. This study highlights the importance of fully considering the various domains of the context and integrating these explicitly into the plan for implementation and evaluation of control programmes. Explicit reporting of these aspects in the resultant publication is also important to guide future work. The contextual factors highlighted in this study may be useful to guide future research and scale up of disease control programmes and demonstrates the importance of close multi-sectoral collaboration in a One Health approach.

Epidemiology of bovine cysticercosis and associated economic losses in the state of Rio Grande do Sul, Brazil.

Bovine cysticercosis (BCC) is the most frequently detected zoonosis in Brazilian slaughterhouses and is considered a problem for public health and beef production chain, requiring epidemiological studies focusing on evaluating its prevalence, spatial distribution, and economic losses in order to improve and adopt specific strategies for BCC control. Thus, this study focused to establish BCC prevalence and spatial distribution in the state of Rio Grande do Sul, Brazil, and estimate the economic losses for cattle farmers suppliers of one exporter slaughterhouse. A set of 70,591 bovine carcasses were postmortem inspected from 2019 to 2020, which came from 134 municipalities located in eight distinct regions in the state of Rio Grande do Sul. The prevalence found was 3.44% (C.I. 95% 3.30-3.57%), and animals infected with unviable cysticerci were more frequently detected (70.56%) than those carrying viable ones (29.44%). The most frequent destination of carcasses and viscera was non-export (65.48%), followed by freezing/salting (25.41%), heat treatment (8.74%), and rendering (0.37%), resulting in a total economic burden of at least US$ 167,868.53 for cattle farmers. Some regions had higher risk for BCC occurrence, such as Porto Alegre, Caxias do Sul, Santa Maria, Ijuí, and Passo Fundo (OR > 1, p < 0.05), respectively. These results highlight the need of adopting prophylactic measures, mainly in specific areas, in order to control BCC and reduce the economic losses for beef production chain.

Zoonotic and vector-borne parasites and epilepsy in low-income and middle-income countries.

Zoonotic and vector-borne parasites are important preventable risk factors for epilepsy. Three parasitic infections - cerebral malaria, Taenia solium cysticercosis and onchocerciasis - have an established association with epilepsy. Parasitoses are widely prevalent in low-income and middle-income countries, which are home to 80% of the people with epilepsy in the world. Once a parasitic infection has taken hold in the brain, therapeutic measures do not seem to influence the development of epilepsy in the long term. Consequently, strategies to control, eliminate and eradicate parasites represent the most feasible way to reduce the epilepsy burden at present. The elucidation of immune mechanisms underpinning the parasitic infections, some of which are parasite-specific, opens up new therapeutic possibilities. In this Review, we explore the pathophysiological basis of the link between parasitic infections and epilepsy, and we consider preventive and therapeutic approaches to reduce the burden of epilepsy attributable to parasitic disorders. We conclude that a concerted approach involving medical, veterinary, parasitological and ecological experts, backed by robust political support and sustainable funding, is the key to reducing this burden.

Placing a monetary value on the human health component of zoonotic diseases: A methodological note with an application to cysticercosis in Africa.

Ideally, policies aiming to tackle zoonotic diseases in animals and reduce the burden of disease in humans should be based on an assessment of the cost and benefits of alternative interventions. However, while the cost of actions targeting diseases in animals and humans and the benefits in terms of increased livestock production can be monetized, it is a challenge to monetize improvements in the quality of life or to life expectancy extensions in humans in zoonotic policy evaluations. This paper proposes a method to monetize the human health benefits derived from zoonotic disease reduction and applies it to cysticercosis in Burkina Faso, Egypt, Ethiopia, Kenya, Nigeria and Uganda. We propose a three-step approach to estimate the human health component of the monetary impact of zoonoses. First, we proxy society's willingness to pay to avoid a disability adjusted life year (DALY) using the annualized value of statistical life (VSL) estimated by of the United States Department of Health and Human Services. Second, we implement a benefit transfer methodology to transfer the US value into the context of the sampled countries, accounting for differences in income levels. Finally, we use the 2016 Global Burden of Disease (GBD, 2018) data on cysticercosis to estimate its monetary impact on human health. All results are estimated in current international dollars using purchasing power parity (USD PPP) exchange rates. In the sampled countries, willingness to pay to avoid a DALY is estimated between USD PPP 2 000 and USD PPP 12 700. In most cases, these estimates fall within the range of 1 and 3 times the GDP per capita. The estimated monetary value of the DALYs due to human infections of cysticercosis per 100 000 people ranges between USD PPP 18 000 and USD PPP 98 000 per year. The proposed methodology might represent a first step towards providing a consistent and unbiased measure of the benefits of interventions targeting prevention, detection and control of zoonotic diseases.

Bovine cysticercosis in Ethiopia: A systematic review and meta-analysis of prevalence from abattoir-based surveys.

Ethiopia is well known for its huge livestock resource that stands number one in Africa and 10th in the world. However, cattle production is constrained by inadequate nutrition, disease, lack of support services and inadequate information. This systematic review and meta-analysis of prevalence of C. bovis in Ethiopia aims to provide a national level prevalence of the parasite from reports conducted in different parts of the country. Due to the expected variation between studies, a random-effects meta-analysis was carried out using the total sample size and number of positives (effect size and standard error of the effect size). Individual study prevalence estimates ranged from 0% to 20% with an overall pooled prevalence of 7% (95% CI = 5%-8%). Studies weighted approximately equal with weights on individual studies ranging from 2% to 2.6% due to high heterogeneity between studies. The meta-analysis indicated that between-study variability was high (τ2 = 0.001; heterogeneity I2 = 99.20% with Heterogeneity chi-square = 4974.9 and, an associated p-value of 0.01). This parasite is indicated to be one of the causes of organ condemnation causing losses of million dollars annually in the country.

The monetary burden of cysticercosis in Mexico.

BACKGROUND: Taenia solium cysticercosis is a public health and agricultural problem in many low and middle-income countries where health education, sanitation, pig management practices and meat inspection infrastructure are insufficient. Cysticercosis affects both human and animal health and has important economic consequences. Very few studies have been conducted to evaluate the monetary burden of cysticercosis. This study aimed at estimating the 2015 costs associated with cysticercosis in humans and pigs in Mexico. METHODS: The monetary burden of human cysticercosis was estimated based on costs incurred by living with and treating epilepsy and severe chronic headaches associated with neurocysticercosis (NCC). The estimated cost of porcine cysticercosis took into consideration losses due to the reduction in the price of cysticercosis-infected animals. Epidemiologic and economic data were obtained from the published literature, government reports, and setting-specific questionnaires. Latin hypercube sampling methods were employed to sample the distributions of uncertain parameters and to estimate 95% credible regions (95% CRs). All results are reported in 2015 U.S.$. FINDINGS: The overall monetary burden associated with NCC morbidity was estimated at U.S.$215,775,056 (95% CR U.S.$109,309,560 -U.S.$361,924,224), with U.S.$436 (95% CR: U.S.$296 -U.S.$604) lost per patient. If loss of future years of income and productivity due to NCC-associated deaths was included, this value increased by U.S.$54.26 million, assuming that these individuals earned Mexico's median wage salary. An additional U.S.$19,507,171 (95% CR U.S.$5,734,782 -U.S.$35,913,487) was estimated to be lost due to porcine cysticercosis. CONCLUSIONS: This study suggests that T. solium cysticercosis results in considerable monetary losses to Mexico.

Levantamento de casos de cisticercose no extremo sul da Bahia no período de 2014 a maio 2017 / Survey of cases of cysticercosis in the south end of Bahia for the period 2014 to may 2017

A cisticercose é um agravo de origem parasitária. A zoonose é relevante no contexto da higiene da carne, do ponto de vista social, econômico - sanitário e de saúde coletiva. A escolha da pesquisa fundamentou-se na carência de estudos acerca do tema na região e na importância da utilização das informações no planejamento e implementação de políticas públicas de saúde, identificar a cidade de origem do animal infectado, calcular o percentual da perda econômica na microrregião em decorrência do número de carcaças com cisticercose. Nos quatro anos, foram abatidos e inspecionados 355.208 bovinos, na microrregião do extremo sul da Bahia (Alcobaça, Caravelas, Itamaraju, Itanhém, Jucuruçu, Lajedão, Medeiros Neto, Mucuri, Nova Viçosa, Prado, Teixeira de Freitas, Ibirapuã e Vereda). O presente trabalho teve como objetivos descrever a prevalência de cisticercose em bovinos abatidos em frigorífico sob inspeção federal no extremo sul da Bahia no período de janeiro de 2014 a maio de 2017.

Bovine cysticercosis and taeniosis: The effect of an alternative post-mortem detection method on prevalence and economic impact.

In Europe, bovine cysticercosis (BCC) is detected by routine meat inspection (MI) at the slaughterhouse. The prevalence of BCC in Belgium based on MI is estimated at 0.23%. MI has a known low sensitivity for animals with localised infections and alternative detection techniques should be considered. A mathematical scenario-analysis model was built to determine the current prevalence of BCC in Belgium based on MI results combined with results of dissection of the predilection sites (PS) and the B158/B60 Ag-ELISA on serum of 614 carcasses found negative on MI. Additionally, the impact of the introduction of the B158/B60 Ag-ELISA at slaughter on the prevalence of BCC and taeniosis and on the economic impact related to Taenia saginata was estimated for Belgium. Data for estimating the economic impact were gathered from multiple sources within the meat and human health sectors and included value loss for infected carcasses, inspection costs, carcass destruction costs, cattle insurance costs and costs related to taeniosis (consultation physician, drugs and laboratory test). The model estimated the current prevalence of BCC to be 42.5% (95% CI: 32.4-60.7%) and the sensitivity of the MI for viable and degenerated cysticerci at only 0.54% (95% CI: 0.37-0.71%). A total of 213,344 viable cysticerci (95% CI: 122,962-386.249) were estimated to be present in the infected carcasses in one year and only 408 (95% CI: 356-464) of these were present in the carcasses detected at current MI. The annual number of human taeniosis cases is estimated at 11,000 by using the sale numbers of niclosamide in Belgium. Implementation of the Ag-ELISA at slaughter (Se = 36.37%; Sp = 99.36%) would greatly reduce the prevalence of BCC to 0.6% and the number of taeniosis cases to 89 in year 10. Unfortunately, the accompanying resulting increase in costs for the animal owners, slaughterhouses and the insurance company, would be extremely high in the first years. Cattle owners would suffer losses of up to €21 million in the first year after implementation of the Ag-ELISA (compared to an annual loss of €3.5 million in the current situation), slaughterhouses of €10 million (compared to €200,000 currently) and the insurance company of almost €6 million (compared to €2.3 million profit currently). Therefore, implementation of the Ag-ELISA might not be feasible and other options for controlling T. saginata should be investigated.

Epidemiology and economic impact of bovine cysticercosis and taeniosis caused by Taenia saginata in northeastern Spain (Catalonia).

BACKGROUND: In Catalonia (north-eastern Spain), Taenia saginata has been described in cattle but its occurrence in humans is unclear. Moreover, whether cattle acquired the infection in Catalonia or outside Catalonia and its economic impact have not been investigated. This study aimed to estimate the prevalence and spatial distribution of bovine cysticercosis in Catalonia (2008-2015), and the burden from T. saginata upon the animal and human sectors in Catalonia (2013-2015). METHODS: Data on cattle diagnosed with cysticercosis at meat inspection were collected and analysed. Cattle movement history was used to identify the most likely place of bovine cysticercosis infection and to investigate its spatial distribution. Data on taeniosis treatment (niclosamide and praziquantel) costs and their supply in Catalonia as well as data on patients attending primary care with diagnosis of taeniosis were collected. The financial impact associated with T. saginata due to carcasses condemned and frozen, meat inspection and human taeniosis was estimated. RESULTS: During 2008-2015, between 18 and 107 cattle were found positive for cysticercosis each year (prevalence at slaughter of 0.010%). Movement history was available for 44% of the infected cattle and in 53% of them Catalonia was identified as the place where the infection was acquired with highest probability. Two significant bovine cysticercosis clusters were detected. The number of patients diagnosed with taeniosis in primary care during the period 2013-2016 was 41-63/year. The overall economic impact of T. saginata (2013-2015) amounted to 154,903 €/year (95% CI: 113,075-196,762). Meat inspection accounted for 81.9% (95% CI: 75.8-86.2%) of the costs, followed by costs due to carcass condemnation and freezing (9.4%; 95% CI: 6.9-12.8%), and taeniosis-associated costs (8.7%; 95% CI: 6.7-11.6%). Costs due to freezing and condemnation of carcasses reached 19,442 €/year (95% CI: 17,528-21,391) (509 €/lightly infected carcass and 1,140 €/heavily infected carcass). Taeniosis-associated costs were estimated at 12,848.5 €/year (237 €/patient). CONCLUSIONS: The public health risk of T. saginata in the area seems to be low. The economic impact due to T. saginata was mainly attributed to meat inspection. The cost due to carcass condemnation and freezing was limited compared to the revenue of the beef sector. Developing and implementing risk-based surveillance is needed to lower the costs of meat inspection. Considering cattle movements might be useful in the development of such a strategy.

Economic impact of bovine cysticercosis and taeniosis caused by Taenia saginata in Belgium.

BACKGROUND: Bovine cysticercosis (BCC) (due to Taenia saginata) is often claimed to cause considerable economic losses to the livestock industry, particularly in beef cattle, but recent studies estimating the economic impact are lacking. The current study aimed to quantify the annual economic impact of BCC in Belgium from 2012 to 2016, by gathering data from diverse sources in the meat and human health sectors. RESULTS: In Belgium, on average, 15 carcasses with generalised infections and 1168 carcasses with localised ones are detected upon meat inspection each year. The highest proportion of the total economic losses due to bovine cysticercosis were borne by the cattle owners with an average economic cost of €3,408,455/year: €2,954,061/year due to BCC insurance, €453,024/year due to value losses of beef of uninsured carcasses (i.e. freezing process) and €1370/year due to destruction costs of uninsured carcasses with generalised infections. The slaughterhouses suffered an economic impact of €210,806/year. They were responsible for inspection costs related to meat inspection in general, administration, processing and deboning of infected carcasses (€597,856/year), value losses (€34,848/year) and destruction costs (€105/year) of carcasses insured by the slaughterhouses (unofficial insurance) (5% of slaughtered animals). On the other hand, the slaughterhouses gained a total of €422,004/year due to unofficial insurance fees. Thirty percent of all slaughtered animals were officially insured against BCC and the insurance company generated an income of €2,322,337/year. The economic impact related to taeniosis (10,991 patients annually) amounted to a maximum of €795,858/year. CONCLUSION: BCC and taeniosis due to T. saginata have a large economic impact in Belgium, mainly due to the insurance costs for BCC. These results indicate the need for reducing the number of BCC and taeniosis cases to avoid the costs and losses related to this parasite.

Taenia solium from a community perspective: Preliminary costing data in the Katete and Sinda districts in Eastern Zambia.

The tapeworm Taenia solium is endemic in Zambia, however its socioeconomic cost is unknown. During a large-scale interventional study conducted in Zambia, baseline economic costs of human and porcine T. solium infections were measured. Questionnaire surveys were conducted within three neighbourhoods in Zambia's Eastern province in 2015 and 2016. A human health questionnaire, capturing costs of clinical symptoms commonly attributable to human cysticercosis and taeniasis, was conducted in randomly selected households (n = 267). All pig-keeping households were administered a pig socioeconomic questionnaire (n = 271) that captured pig demographic data, costs of pig-keeping, and economic losses from porcine cysticercosis. Of all respondents 62% had reportedly experienced at least one of the surveyed symptoms. Seizure-like episodes were reported by 12%, severe chronic headaches by 36%, and vision problems by 23% of respondents. These complaints resulted in 147 health care consultations and 17 hospitalizations in the five years preceding the study, and an estimated productivity loss of 608 working days per year. Of all pigs 69% were bought within villages. Nearly all adult pigs were sold to local traders, and tongue palpation for detection of cysticerci was commonly performed. Reportedly, 95% of pig owners could not sell tongue-positive pigs, while infected pigs fetched only 45% of the normal sale value. These preliminary costing data indicate that human and porcine T. solium infections substantially impact endemic areas of Eastern Zambia. A full socioeconomic burden assessment may enable improved T. solium management in sub-Saharan Africa.

Epidemiological updates and economic losses due to Taenia hydatigena in sheep from Sardinia, Italy.

The aim of this study was to investigate the epidemiology and transmission of Taenia hydatigena in sheep and dogs from Sardinia and the economic estimation of losses due to this metacestodosis in lambs. A total of 7781 Sarda breed lambs were examined at abattoirs for the detection of Cysticercus tenuicollis or necrotic-haemorrhagic tracks of their migration. Morphological and molecular identification of parasites was carried out. Individual faecal samples from 300 dogs were examined for copromicroscopic investigations and coproELISA assay. An overall prevalence of 14.6% for T. hydatigena cysticercosis was found in the examined lambs. In total, 10,807 parasitary tracks were found, with an abundance of 1.39 and an average intensity of 9.52. The molecular analysis of the isolates showed an overall pairwise nucleotide divergence for the CO1 and ND1 was of 0-3.1 and 0-3.3%, respectively. Low intra- and interspecific variation was recorded for C. tenuicollis isolates used in this study which suggested the absence of differentiation. Microscopic examination of dog faeces showed a total prevalence of 31.3% for endoparasites in the examined samples (94/300). Taeniid eggs were found in 8.3% of the dogs. The results of the monoclonal antibody ATH4 ELISA test showed a prevalence of 11% (33/300) for T. hydatigena coproantigens. The total economic costs related to cysticercosis amounted to almost € 330,000. The prevalence of C. tenuicollis in 14.6% of 30-40-day-old lambs highlights the high parasitic pressure by T. hydatigena in the territory of Sardinia, Italy.

Bovine cysticercosis in slaughtered cattle as an indicator of Good Agricultural Practices (GAP) and epidemiological risk factors.

This study focused on estimating the economic losses resulting from cysticercosis at beef cattle farms that supply an export slaughterhouse located in the state of São Paulo, Brazil, and to identify the epidemiological risks factors involved in the disease to ascertain if these farms adopt Good Agricultural Practices (GAP). To this, we used data recorded in 2012 by Brazil's Federal Inspection Service (SIF) on the daily occurrence of the disease, according to the farm from which the animals originated. In addition, the associated risk factors were determined based on a case-control study at 48 farms. Cysticercosis was detected in 2.26% (95% CI 2.2-2.33) of the 190,903 bovines supplied by 556 farms in the following four states: 2.92% (95% CI 2.83-3.03) in São Paulo, 1.81% (95% CI 1.71-1.93) in Minas Gerais, 0.71% (95% CI 0.6-0.82) in Goiás and 1.11% (95% CI 0.79-1.57) in Mato Grosso do Sul, with significant differences in the epidemiological indices of these states. Cysticercosis was detected at 58.45% (95% CI 54.36-62.55) of the farms of this study, representing estimated economic losses of US$312,194.52 for the farmers. Lower prevalence of this disease were found at the farms qualified for exports to the European Union, indicating a statistically significant difference from those not qualified to export to Europe. The access of cattle to non-controlled water sources, as well as sport fishing activities near the farms, was identified as risk factors. Cysticercosis causes considerable losses in Brazil's beef supply chain, with lower prevalence appearing only at farms qualified to export to the European Union. As for the access of cattle to non-controlled water sources, this is an indication that GAP are not implemented by some farms, demonstrating the violation of international agreements by the industry and the farms.

Control of cysticercosis in Madagascar: beware of the pitfalls.

Taenia solium cysticercosis is a zoonosis of public health importance in areas where the disease is endemic, with significant economic impacts on human health and the swine industry. Several gaps remain in the epidemiology of the parasite and the strategies of control in developing countries. We detail the key factors to consider in Madagascar in terms of the porcine husbandry system, Taenia transmission cycle, and diagnosis of cysticercosis in pigs, in order to better estimate the sanitary and economic impacts of this parasitic disease as well as to define an integrated control program.

The economic impact of pig-associated parasitic zoonosis in Northern Lao PDR.

The parasitic zoonoses human cysticercosis (Taenia solium), taeniasis (other Taenia species) and trichinellosis (Trichinella species) are endemic in the Lao People's Democratic Republic (Lao PDR). This study was designed to quantify the economic burden pig-associated zoonotic disease pose in Lao PDR. In particular, the analysis included estimation of the losses in the pork industry as well as losses due to human illness and lost productivity. A Markov-probability based decision-tree model was chosen to form the basis of the calculations to estimate the economic and public health impacts of taeniasis, trichinellosis and cysticercosis. Two different decision trees were run simultaneously on the model's human cohort. A third decision tree simulated the potential impacts on pig production. The human capital method was used to estimate productivity loss. The results found varied significantly depending on the rate of hospitalisation due to neurocysticerosis. This study is the first systematic estimate of the economic impact of pig-associated zoonotic diseases in Lao PDR that demonstrates the significance of the diseases in that country.

Abattoir prevalence, organ distribution, public health and economic importance of major metacestodes in sheep, goats and cattle in Fars, southern Iran.

Some of the metacestodes are not only zoonotic but are also responsible for severe tissue damage, reduction in milk and meat production, and considerable economic loss due to condemnation of the infected organs of the herbivorous animals. The aim of the present study was to determine the prevalence of Cysticercus ovis, Cysticercus tenuicollis, hydatid cyst and Coenurus gaigeri in sheep and goats and Cysticercus bovis, Cysticereus tenuicollis and hydatid cyst in cattle. A total of 1050 sheep, 950 goats and 500 cattle slaughtered at Shiraz Slaughterhouse were carefully examined for these metacestodes. Cysticercus tenuicollis was found in 184 (17.52%) sheep and 523 (55.05%) goats. The prevalence of C. tenuicollis was higher in males than females (P<0.01), and was higher in goats compared to sheep (P<0.01). Hydatid cyst was found in 478 (45.52%) sheep and 95 (10.0%) goats and its prevalence was higher in older animals compared to the younger ones. Coenurus gaigeri was found in 5 (0.48%) sheep and 17 (1.79%) goats and Cysticercus ovis was found in one male sheep only (0.09%). Cysticercus bovis was found in 3 male cattle (0.6%) and hydatid cyst was found in 58 (11.6%) cattle. The prevalence of hydatid cyst was higher in older cattle compared to the younger ones and higher in females than males. These results suggest that the high prevalence of the metacestodes infestations in this area is a great concern for both medical and veterinary authorities to design therapeutic and preventive programs to overcome this problem.

Prevalence of bovine cysticercosis in slaughtered cattle in Iran.

Bovine cysticercosis is an important food safety issue and can cause economic loss. A cross sectional study on Taenia saginata cysticercosis was carried out in slaughtered cattle in Iran in order to determine the infection rate during a three-years period, from 2005 to 2007. A total of 4,534,105 cattle were examined by routine meat inspection. The results showed that 11,410 cattle (0.25 %) were infected with Cysticercus bovis; among those 1,041 carcasses (0.02%) were condemned. In such carcasses the metacestodes caused extensive damage in the vicinity of cysts in infected cattle. The rejected carcasses had an average of 410 thousands USD loss annually.

Estimation of the cost of Taenia solium cysticercosis in Eastern Cape Province, South Africa.

OBJECTIVES: To provide a comprehensive estimate of the societal costs of Taenia solium cysticercosis for the Eastern Cape Province (ECP), South Africa, as an objective measure of its impact in this endemic area. METHODS: Epidemiological data on the prevalence of epilepsy, proportion of epilepsy cases due to neurocysticercosis (NCC) and consequences of cysticercosis were gathered from published and unpublished sources. Economical data were mostly obtained from governmental sources. Three methods were used for estimating productivity losses. Monte Carlo sampling was used to represent the uncertainty of the estimates with 95% Credible Intervals (95% CI). The estimation is for 1 year using a societal approach. All costs are reported in 2004 US Dollars. RESULTS: Overall, there were an estimated 34 662 (95% CI: 17 167-54 068) NCC-associated cases of epilepsy in ECP in 2004. The overall monetary burden (in million of US Dollars) was estimated to vary from US Dollars 18.6 (95% CI: US Dollars 9.0-32.9) to US Dollars 34.2 (95% CI: US Dollars 12.8-70.0) depending on the method used to estimate productivity losses. The agricultural sector contributed an average of Dollars 5.0 million. The prevalence of epilepsy, proportion of productivity reduction and the proportion of epilepsy cases attributable to NCC had the largest impact on the overall estimates. CONCLUSION: This preliminary estimate suggests that T. solium cysticercosis results in considerable monetary costs to a region that is already economically constrained. Because this infection is preventable, these results could guide stakeholders in deciding where to invest scarce health and agricultural resources in their countries.

Assessing the burden of Taenia solium cysticercosis and echinococcosis.

This collection of articles provides an account of the papers delivered at the 19th International Conference of the World Association for the Advancement of Veterinary Parasitology (WAAVP)(held in New Orleans, LA, USA, from 10 to 14 August 2003) in a symposium session on assessing the burden of Taenia solium cysticercosis and echinococcosis organised and chaired by A. Lee Willingham III from the WHO/FAO Collaborating Center for Research and Training on Emerging and other Parasitic Zoonoses in Denmark and Peter M. Schantz from the Parasitic Diseases Division of the US Centers for Disease Control and Prevention, USA. The focus was on the persistence of the zoonotic parasitic diseases cysticercosis, caused by the pork tapeworm T. solium, and echinococcosis,caused by species of the tapeworm Echinococcus, and why these diseases are given very little attention on the national and international agendas in spite of the availability of tools to detect, treat,control and prevent them when it is quite clear in most instances that they are clearly associated with and help perpetuate poverty. A major reason for this is that in many endemic areas the presence and impact of these diseases are not known due to the lack of investigation and information thus policymakers are not aware of their burden and benefits of their control. Documentation is also needed to help increase awareness of the international community and hopefully result in financial and technical support being made available. Thus, burden assessments of cysticercosis and echinococcosis provide an essential evidence base for securing political will and financial and technical support as well as providing a basis for cost-benefit analysis of prevention and control efforts. In order to make an appropriate and full burden assessment one must consider the health, agricultural, social and other impacts of these parasitic zoonoses comprehensively. During the symposium presentations were given concerning current ongoing initiatives to assess the burden of cysticercosis and echinococcosis and examples of the impact of these diseases in both developing and developed countries were provided. In addition, cost factors related to vaccines for these cestode diseases were discussed and the possibilities for technical and financial support from multilateral agencies for assessments and interventions presented.

Regional status, epidemiology and impact of Taenia solium cysticercosis in Western and Central Africa.

In West Africa, Taenia solium cysticercosis in both pigs and man has been reported in Benin, Burkina-Faso, Ghana, Ivory Coast, Senegal and Togo, and although official data are lacking, T. solium is anticipated to be present in most of the pig-raising regions of other West African countries as well. In some regions of Nigeria, the prevalence of porcine cysticercosis and human taeniosis is quite high (20.5 and 8.6%, respectively). Surprisingly, however, no cases of human cysticercosis have been reported, although epilepsy is very common. Large epidemiological surveys have only been carried out in Togo and Benin, where the prevalence of human cysticercosis was 2.4 and 1.3%, respectively. In Central Africa, porcine and human cysticercosis are (hyper)-endemic in Rwanda, Burundi, the Democratic Republic of Congo and Cameroon. The parasite also has been reported in pigs in Chad and Angola. Cysticercosis has been shown to be one of the major causes of epilepsy in Cameroon with figures as high as 44.6%. Cameroon is one of the few countries where the taeniosis-cysticercosis complex has been examined more in detail. In the Western province of Cameroon large scale surveys have shown that active cysticercosis is present in 0.4-3% of the local population and in 11% of the village pigs. However, the prevalence of adult T. solium was only 0.1%, which underscores the frequency of the T. solium paradox. Based on the available information, a very conservative economic estimate indicates that the annual losses due to porcine cysticercosis in 10 West and Central African countries amount to about 25 million Euro. The financial losses due to human cysticercosis are very difficult to estimate, but are certainly exceeded by the social impact of the disease, especially because of the particular perception of epilepsy in many African communities. It is concluded that the true prevalence of T. solium cysticercosis in pigs and humans in Central and West Africa remains underestimated because of unreliable slaughterhouse data and the lack of awareness and diagnostic facilities in the public health sector.