The socio-economic burden of cystic echinococcosis in Morocco: A combination of estimation method

Cystic echinococcosis (CE) is a major zoonosis in Morocco despite the launch of a national control programme in 2005. As its economic consequences have not been studied yet in Morocco, this study estimated CE impact in terms of monetary losses, disability-adjusted life years (DALY), and DALY for zoonotic diseases (zDALY) in the entire country and in specific regions for the 2011 to 2014 period. The direct monetary losses were related to organ seizure from infected animal in slaughterhouses, and to healthcare expenses as well as lost wages for infected humans. Animal production losses concerned milk yield, fertility, carcass weight, and wool production. Losses due to human infection were also composed of disability and productivity losses at work. Monte Carlo simulations were used to estimate monetary losses and zDALY values. Nationwide, the estimated DALY was 0.5 years per 100,000 persons per year, and the zDALY was 55 years per 100,000 persons per year. Total yearly losses were estimated at 73 million USD (54–92 million USD). However, losses differed significantly among regions. Most of the economic losses consisted of unperceived consequences, i.e. decreased animal production and reduced productivity of asymptomatic individuals. Future studies should determine the socioeconomic and epidemiological factors underlying the differences in economic losses among regions to develop better adapted control programmes.

Cystic echinococcosis (CE) is a major neglected zoonosis in Morocco, despite the launch of a national control programme in 2005. The first study on CE in Morocco dates back to 1924. However, no evaluation of economic losses was made until now. The present study estimated the economic losses caused by CE in Morocco, at the national and regional scale, by combining financial and non-financial methods. Estimation of the direct and indirect losses caused by CE infection in humans and livestock (sheep, cattle, goats and camels) highlighted the important disease burden nationwide, amounting to 0.07% of Morocco Gross Domestic Product. The combination of methods brought information on the different CE-linked economic losses, including the unperceived consequences. These results indicate that the national CE control strategy did not result in a decrease of the disease burden, which calls for its evaluation and improvement.

Cystic echinococcosis in the Eastern Mediterranean region: Neglected and prevailing!

Cystic echinococcosis (CE) is distributed worldwide, extending from China to the Middle East and from Mediterranean countries to the sub-Saharan Africa and South America. According to WHO, one million people around the world are suffering from CE with an estimated burden of 183,573 DALYs. The annual monetary burden of the disease due to treatment costs and CE-related livestock losses has been estimated at US$ 3 billion. CE is endemic in all countries within the WHO Eastern Mediterranean Regional Office (EMRO). The region, which includes most of the Middle East and North Africa, is one of the most ancient foci of the domestic cycle of CE and is recognized as one of the major hotspots of CE. There are 22 countries in the EMRO, where about 688 million people are living at risk of CE. In many EMRO countries, little is known about CE epidemiology and transmission. WHO included echinococcosis in a list of 17 neglected tropical diseases (NTDs) and 12 neglected zoonotic diseases (NZDs). Accordingly, different regional offices of WHO organized several initiatives for CE control and prevention. WHO’s Western Pacific regional office considered echinococcosis as one of the region’s major health topics, and several preventive measures have been implemented in the American region with the support of Pan American Health Organization (PAHO) in Argentina, Peru, Uruguay, and Chile. Although CE is endemic in all 22 EMRO countries, surprisingly, CE is absent from the health topics list of diseases and conditions in this region. Therefore, CE clearly requires further attention in the WHO EMRO agenda, and the need for elaboration of specific measures for CE control is becoming apparent in EMRO countries, where substantial collaborations among the member states and WHO EMRO is of paramount importance. Major topics of collaborative activities include training programs and health communication on different aspects of CE control, analysis of CE burden, national and international surveillance and disease registry systems, technical support to promote epidemiological studies for collecting baseline data, cost–benefit analysis of control interventions, and intersectoral cooperation among the agriculture, veterinary, medical, and health sectors.

[COMPARATIVE ANALYSIS OF THE COST OF TREATMENT OF ECHINOCOCCOSIS BY THERAPEUTIC AND SURGICAL METHODS (BASED ON THE STEP-DOWN METHODOLOGY)]

The aim of the study was to carry out a comparative economic analysis of the costs of therapeutic and surgical treatment of liver echinococcosis based on the developed methodological approaches and principles for calculating the cost of complex medical services in accordance with the «step-down» methodology. The model for calculating the cost of complex medical services for the treatment of echinococcosis was justified. The sum of costs of outpatient and inpatient units that directly provide medical care (direct costs) to the costs of support centers (indirect costs) was adjusted, which among simple medical services based on the chosen criterion were distributed. Calculation of costing items out on the basis of the direct-cost costing method was carried. Based on the proposed model, a comparative analysis of the cost of treatment of liver echinococcosis using therapeutic and surgical methods was carried out. As a result of the study, it was proved that the therapeutic method is less expensive than the surgical method. This is the basis to recommend it for wider use in medical practice, especially in cases when there is a problem of choosing the method of treatment of echinococcosis. Cost optimization is facilitated by a combination of surgical intervention and therapeutic treatment.

Cystic echinococcosis in animals and humans of Maharashtra State, India

Echinococcosis/hydatidosis which is a neglected parasitic zoonosis in the developing country like India. The study was conducted during April, 2010 to March, 2017 to determine the prevalence among slaughtered food animals, dogs and human. The samples were collected from the various slaughterhouses situated in different regions of Maharashtra state. A total of 9464 cattle (male), 3661 buffalo, 47189 sheep, 33350 goats and 13579 pigs were scientifically examined during PM inspection at different slaughterhouses. The study revealed that the prevalence of disease in cattle (3.00%) was highest followed by buffalo (2.05%), pig (1.28%), sheep (0.09%) and goat (0.01%), by PM examination. The average estimated economic losses (direct and indirect) due to hydatidosis were Rs. 8,65,83,566 in cattle, Rs. 44,33,93,900 in buffalo, Rs. 7,24,50,615 in sheep, Rs. 1,88,29,359 in goat and Rs. 5,20,49,081 in pigs. Dog faecal samples analyzed and showed the prevalence of echinococcosis as 4.34% (19/438) by sedimentation method and positive samples were confirmed by PCR assay, whereas in high risk human, 11.09% sera samples were found to be positive for echinococcosis. However, based on data collection for seven years, 58 patients were found to be surgically operated for hydatid cyst removal. The results of the present study indicated that cystic echinococcosis/hydatidosis is prevalent in both human and animal population in study areas which attracts serious attention from veterinary and public health authority to reduce economic burden and in designing appropriate strategy for prevention and control of disease.

[Cost Analysis of Dog Deworming in Echinococcosis Control Program in Daofu，Sichuan Province]

OBJECTIVE

To estimate the cost of dog deworming in Daofu, Sichuan Province and analyze the factors influencing the cost, in order to provide a scientific basis for the investment for echinococcosis control.

METHODS

Thirty villages were randomly selected in Daofu, Sichuan Province in November 2015, according to the proportion of agricultural and pastoral areas. Data concerning the cost during each step of dog deworming were collected. The unit cost was estimated, the cost composition in each step, element, and institution were described, and the main cost-influencing factors were analyzed using the linear regression method.

RESULTS

The mean cost of dog deworming in the 30 surveyed villages was 3.76 yuan/dog-times, comprising drug cost of 0.38 yuan/dog-times, bait cost of 0.37 yuan/dog-times, drug delivery cost of 0.09 yuan/dog-times, mobilization cost of 0.19 yuan/dog-times, household deworming cost of 2.05 yuan/dog-times, faeces disposal cost of 0.35 yuan/dog-times, training cost of 0.29 yuan/dog-times, and supervision cost of 0.04 yuan/dog-times. Among the deworming steps, household deworming cost occupied the most （2.05 yuan/dog-times）; among the cost elements, labour cost had the highest proportion （2.55 yuan/dog-times）; among the different-leveled institutions, village-level cost was the most important part（2.82 yuan/dog-times）. Linear regression analysis revealed that the type of production and the distance among households were the major influencing factors. The labour price was the most sensitive factor for cost-estimation in the dog deworming activities.

CONCLUSION

The labor cost of dog deworming is very high. Governments should increase investment according to local situations.

[Hospital care expenses caused by acute fascioliasis, cystic echinococcosis, and neurocysticercosis in Santiago, Chile]

BACKGROUND

Acute fascioliasis (FA), cystic echinococcosis (CE) and neurocysticercosis (NCC) are three endemic parasitic diseases in Chile for whom there is scarce information about the economic impact they represent during management at the hospital.

AIMS

To quantify and compare hospital care expenses caused by these three endemic helminth infections in a Chilean hospital.

METHODS

Retrospective analysis of hospital costs at a referral hospital in Santiago between 2006 and 2010. Hospital databases were used to identify patients with the corresponding infections, and those with sufficient data on hospital costs were included.

RESULTS

A total of 16 patients representing 21 cases were identified and analyzed: four with AF, eleven with CE, and six with NCC. Median hospital expenses for cases with AF were US$ 1799 and mainly caused by bed-day costs. Median hospital costs for cases of CE were US$ 4707 and the most important costs components were medications, bed-day costs and consumables. NCC patients had median costs of US$ 1293, which were mainly due to bed-day costs. Non-parenchymatous or mixed forms of NCC showed a trend toward higher hospital costs compared with parenchymatous forms.

CONCLUSIONS

Although helminth infections in Chile, an upper middle income country, are declining and considered rare in routine clinical practice, hospital care expenses caused by patients with AF, CE, and NCC are high and might still present an important economic burden to the Chilean healthcare system.

Cystic echinococcosis in the Province of Álava, North Spain: the monetary burden of a disease no longer under surveillance

Cystic echinococcosis (CE) is endemic in Spain but has been considered non-endemic in the province of Álava, Northern Spain, since 1997. However, Álava is surrounded by autonomous regions with some of the highest CE prevalence proportions in the nation, casting doubts about the current classification. The purpose of this study is to estimate the frequency of CE in humans and animals and to use this data to determine the societal cost incurred due to CE in the Álava population in 2005. We have identified epidemiological and clinical data from surveillance and hospital records, prevalence data in intermediate (sheep and cattle) host species from abattoir records, and economical data from national and regional official institutions. Direct costs (diagnosis, treatment, medical care in humans and condemnation of offal in livestock species) and indirect costs (productivity losses in humans and reduction in growth, fecundity and milk production in livestock) were modelled using the Latin hypercube method under five different scenarios reflecting different assumptions regarding the prevalence of asymptomatic cases and associated productivity losses in humans. A total of 13 human CE cases were reported in 2005. The median total cost (95% credible interval) of CE in humans and animals in Álava in 2005 was estimated to range between €61,864 (95%CI%: €47,304-€76,590) and €360,466 (95%CI: €76,424-€752,469), with human-associated losses ranging from 57% to 93% of the total losses, depending on the scenario used. Our data provide evidence that CE is still very well present in Álava and incurs important cost to the province every year. We expect this information to prove valuable for public health agencies and policy-makers, as it seems advisable to reinstate appropriate surveillance and monitoring systems and to implement effective control measures that avoid the spread and recrudescence of the disease.

The monetary burden of cystic echinococcosis in Iran

Cystic echinococcosis (CE) is a globally distributed parasitic infection of humans and livestock. The disease is of significant medical and economic importance in many developing countries, including Iran. However, the socioeconomic impact of the disease, in most endemic countries, is not fully understood. The purpose of the present study was to determine the monetary burden of CE in Iran. Epidemiological data, including prevalence and incidence of CE in humans and animals, were obtained from regional hospitals, the scientific literature, and official government reports. Economic data relating to human and animal disease, including cost of treatment, productivity losses, and livestock production losses were obtained from official national and international datasets. Monte Carlo simulation methods were used to represent uncertainty in input parameters. Mean number of surgical CE cases per year for 2000-2009 was estimated at 1,295. The number of asymptomatic individuals living in the country was estimated at 635,232 (95% Credible Interval, CI 149,466-1,120,998). The overall annual cost of CE in Iran was estimated at US$232.3 million (95% CI US$103.1-397.8 million), including both direct and indirect costs. The cost associated with human CE was estimated at US$93.39 million (95% CI US$6.1-222.7 million) and the annual cost associated with CE in livestock was estimated at US$132 million (95% CI US$61.8-246.5 million). The cost per surgical human case was estimated at US$1,539. CE has a considerable economic impact on Iran, with the cost of the disease approximated at 0.03% of the country's gross domestic product. Establishment of a CE surveillance system and implementation of a control program are necessary to reduce the economic burden of CE on the country. Cost-benefit analysis of different control programs is recommended, incorporating present knowledge of the economic losses due to CE in Iran.

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.

[Cost analysis of early diagnosis of hydatidosis in children of 5 and 12 years old in the province of Ñuble, Bío-Bío Region, Chile]

This study conducted a cost analysis of different interventions in the early diagnosis of hydatidosis between the years 2006 -2007 in the Province of Nuble, Bio-Bio Region of Chile. The aim was to estimate the costs of early diagnosis of this condition. We included all children of 5 and 12 years old in rural areas of the province. Data collection activities were identified which included specific antibody measurements (indirect ELISA) and an abdominal ultrasound. For the determination of costs, direct and indirect costs were identified using the methodology of activity-based costs. The results demonstrate that the preventive diagnosis costs S17.183 Chilean pesos per child (S35 US dollars), thus making this intervention of lower cost than waiting until the person becomes ill with this disease.

Prevalence of cystic echinococcosis in slaughtered cattle in Afyonkarahisar

This study was carried out in 1001 cattle that were slaughtered in 3 abattoirs in the Afyonkarahisar district of western Turkey. Abattoirs were visited twice a week and internal organs of the cattle were examined for cystic echinococcosis (CE). The number of organs discarded because of CE was recorded. CE was found in 295 (29.47%) out of 1001 cattle studied. CE was found in 113 (44.31%) out of 255 cows and 182 (24.39%) out of 746 bulls. This difference was statistically significant (p < 0.001). CE was observed only in liver of 130 (44.06%) cattle, only in lungs of 91 (30.85%); only in hearts of 2 (0.68%) and only in the kidney of 1 (0.34%); in both livers and lungs of 70 (23.73%), and in both hearts and lungs of 1 (0.34%). Also, the rate of CE was significantly higher in cows than bulls in terms of organ predilection (p < 0.001). Forty three livers were completely discarded along with half of 18 livers, a quarter of 37 livers and the remaining livers in various degrees. Forty four lungs were completely destroyed along with half of 13 and a quarter of 21 whereas 3 hearts and one kidney were completely destroyed. The fertility rate of cysts was found to be 5.42%. In this study the prevalence of CE in cattle in Afyonkarahisar district has been documented and possible economic losses due to CE were emphasized.

Global socioeconomic impact of cystic echinococcosis

Because the human and economic losses of cystic echinococcosis are substantial, global prevention and control measures should be increased.

Cystic echinococcosis (CE) is an emerging zoonotic parasitic disease throughout the world. Human incidence and livestock prevalence data of CE were gathered from published literature and the Office International des Epizooties databases. Disability-adjusted life years (DALYs) and monetary losses, resulting from human and livestock CE, were calculated from recorded human and livestock cases. Alternative values, assuming substantial underreporting, are also reported. When no underreporting is assumed, the estimated human burden of disease is 285,407 (95% confidence interval [CI], 218,515–366,133) DALYs or an annual loss of US $193,529,740 (95% CI, $171,567,331–$217,773,513). When underreporting is accounted for, this amount rises to 1,009,662 (95% CI, 862,119–1,175,654) DALYs or US $763,980,979 (95% CI, $676,048,731–$857,982,275). An annual livestock production loss of at least US $141,605,195 (95% CI, $101,011,553–$183,422,465) and possibly up to US $2,190,132,464 (95% CI, $1,572,373,055–$2,951,409,989) is also estimated. This initial valuation demonstrates the necessity for increased monitoring and global control of CE.

Methods for assessing the burden of parasitic zoonoses: echinococcosis and cysticercosis

Cysticercosis and echinococcosis cause illness and productivity losses in human and agricultural animal populations. Recent studies suggest that these diseases have large societal impacts on endemic areas. Estimates of burden provide essential, evidence-based data for conducting cost-benefit and cost-utility analyses that will secure political will, and financial and technical resources. To evaluate the burden, the monetary and non-monetary impacts of these zoonoses on human health, agriculture and society must be considered comprehensively. In this article, we review the framework used to assess the burden of cysticercosis and echinococcosis, and the data needed to estimate the extent of the problem for societies.

Economic effects of echinococcosis in a disease-endemic region of the Tibetan Plateau

This report attempts to quantify the economic losses due to Echinococcus multilocularis and E. granulosus in Shiqu County, Sichuan, People's Republic of China, as well as illustrate the cost effectiveness of dog anthelmintic prophylaxis combined with a sheep and goat vaccination program in terms of disability-adjusted life years (DALYs) saved. We evaluated human losses associated with treatment costs and loss of income due to morbidity and mortality, in addition to production losses in livestock due to E. granulosus infection. Annual combined human and animal losses (95% confidence interval) is estimated to reach 218,676 U.S. dollars (189,850-247,871 U.S. dollars) if only liver-related losses in sheep, goats, and yaks are taken into account. This equates to approximately 3.47 U.S. dollars per person annually or 1.4% of per capita gross domestic product. However, total annual losses can be nearly 1,000,000 U.S. dollars if additional livestock production losses are assumed. Eventual prevention of 65-95% of annual losses due to cystic echinococcosis is suggested with proposed biannual dog anthelmintic prophylaxis and a sheep and goat vaccination program. Prevention of 9-50% of human alveolar echinococcosis-associated losses is suggested based on stochastic models for the current epidemiologic situation. The median estimated cost of the program would be approximately 56,000 U.S. dollars per year, which is a fraction of the estimated combined livestock and human financial losses due to the disease. Overall cost for the proposed control program is within the World Health Organization second most cost-effective band of less than 150 U.S. dollars per DALY averted. However, cost per DALY averted would be less than 25 U.S. dollars dollars for the human health sector if cost sharing was implemented between the public health and agricultural sectors based on proportional benefit from control.

Echinococcosis in Tunisia: a cost analysis

Echinococcus granulosus infection is a preventable zoonosis of human and veterinary public health importance in Tunisia. We aimed to comprehensively quantify human and animal echinococcosis losses in Tunisia. Itemized cost menus were developed for the health of both domestic animals and humans, and for productivity monetary losses. The incidence and prevalence of the disease in all species were obtained from national and personal reports. The domestic animal and human costs of echinococcosis in Tunisia were estimated using age-stratified rates and losses, productivity losses (including those not formally employed) and Monte Carlo sampling to represent the uncertainty inherent in some epidemiological and economic values. Echinococcosis in Tunisia causes significant direct and indirect losses in both humans and animals of approximately US dollars 10-19 million annually. These estimates are based on numerous methodological improvements over previous studies and are of considerable consequence relative to Tunisia's US dollars 21.2 billion gross domestic product. A cost-benefit analysis of control programmes using the methodological advances presented here and regional comparison to other endemic diseases is warranted. These may provide information to assist policy decision-makers in prioritizing the allocation of scarce resources.

Socio-economic impact of cystic echinococcosis and of its control: some data and considerations

The socio-economic impact of cystic echinococcosis (CE), caused by Echinococcus granulosus, is reviewed with special reference to the following topics: consequences in man and livestock, costs and benefits of control programmes and economic procedures for evaluating control programmes. Examples of some important costs and benefits are given. Many consequences in man and livestock are difficult to evaluate from an economic point of view, because some basic data are difficult to obtain in many countries. However, the socio-economic evaluation of the consequences of CE and of the present and future control actions proves indispensable to best use available resources and possibly tailor control stategies.

Cystic echinococcosis in Jordan: socioeconomic evaluation and risk factors

The costs of illness and surgical intervention for human cystic echinococcosis (CE) cases in Jordan was economically evaluated by 77 surgeons and 77 CE patients. The cost of diagnosis for each CE case was 111.30 US Dollars and 146.20 US Dollars as estimated by surgeons and patients, respectively. The cost of surgical extraction of hydatid cysts for each case was 590.20 US Dollars and 638.50 US Dollars as estimated by both groups, respectively. Knowledge, attitudes and practices (KAP) of 77 CE patients as well as several Jordanian groups with different occupations including 144 shepherds, 119 settled livestock owners, 25 slaughter house workers, 400 university students and 80 inhabitants of a CE focus in southern Jordan were analyzed through a set of questionnaires. All of these groups had poor knowledge of CE, especially the source and causes of infection. All practices and attitudes of each group favored continuous transmission of the parasite and indicate the need for the implementation of a proper control program in the country.

Prevalence and economic importance of cystic echinococcosis in slaughtered ruminants in Burdur, Turkey

This study was conducted between April 2000 and March 2001, in 12-month period. During the study, local slaughterhouses were visited periodically for 1 year to examine the internal organs (livers, lungs, spleens and hearts) for the presence of cysts and total 1355 cattle, 218 sheep and 104 goats were examined for the cystic echinococcosis (CE). It was found that 13.5% of cattle, 26.6% of sheep and 22.1% of goats were infected with this disease. While cysts in cattle (P < 0.001) and goats (P > 0.05) were found mostly in lungs (88.5 and 82.6%, respectively), but they were mostly found in livers (P > 0.05) in sheep. In addition to this, three spleens and one heart in cattle were infected with CE. In this study, the prevalence of CE and the number of cysts in ruminants were found different when the cattle, sheep and goats examined were stratified based on age. The prevalence and the number of cysts increased with age approaching an asymptotic prevalence of one in the oldest animals (P < 0.05). The number of cysts in cattle, sheep and goats were increasing at a rate of 0.31, 0.63 and 0.42/year, respectively. The economic decrease in the value of the carcasses because of the discarded liver and lung as a result of CE was estimated as 1.1% (7.5 US dollars per cattle) for cattle, 4.37% (3.2 US dollars per sheep) for sheep and 4.26% (2.9 US dollars per goat) for goats. The minimum total loss for all infected animals was determined to be 583 US dollars in infected animals, based on the market prices in the year 2002.

Economic effects of echinococcosis

Cystic echinococcosis (CE) has a number of important economic effects. The most tangible of these is the cost of expensive medical treatment for human cases. Each confirmed case of CE can cost the health services or individual several thousand dollars. In addition to these costs, the additional cost of loss of edible offal from agricultural animals is well known. This may result in the entire loss of an infected organ or at least the trimming and downgrading of that organ, depending on local legislature. However, these losses may only be a relatively small percentage of the economic losses attributed to CE. Recent evidence suggests, through quality of life surveys, that patients treated for CE never fully recover and have a significant and permanent decreased quality of life. This has yet to be translated into monetary terms, but it almost certainly will result in the loss of income, possibly through a lower paid job, and/or the additional expense of increased ill health. Furthermore, in most reports, between 1 and 2% of CE cases are fatal. The death of these individuals results in the loss of the potential lifetime's economic output of these individuals. With alveolar echinococcosis the mortality rate is much higher and such consequences more severe. There is also a considerable amount of Soviet literature, and small amounts published elsewhere which suggests that CE also significantly affects animal productivity. Thus, infected sheep tend to give birth to fewer lambs, have lower levels of food conversion, produce less milk and have poorer quality fleeces then non-infected sheep. The total cost of the disease is the sum of the various costs to the health services, costs of morbidity and losses in animal productivity. Due to the uncertainty of many of these costs, it is appropriate to model these losses using techniques that can give a range of cost estimates. By using analytical techniques such as Monte-Carlo analysis, on parameters that are difficult to determine accurately, all such variables can be randomly varied simultaneously along likely frequency distributions. The results of this give a useful sensitivity analysis of economic costs. In addition, the purchasing power of money in the local economy must also be taken into account. One US $ buys much more in a developing country than in an industrialized economy. Consequently, each lost $ will be more acutely felt in poor countries. Estimates of the financial burden of disease are beneficial in deciding priorities for control. They are also potentially useful tools to lobby donors or non-governmental organizations to fund control programs in poor countries.

Progress in control of hydatidosis using vaccination--a review of formulation and delivery of the vaccine and recommendations for practical use in control programmes

A vaccine to protect sheep, goats, and bovines against hydatid disease caused by the cysts of Echinococcus granulosus is prepared as a recombinant fusion protein expressed in Escherichia coli. Solubilised inclusion bodies are injected, together with Quil A, subcutaneously on two occasions 1 month or more apart, and induce protection against infection which lasts for at least 12 months. A third injection given 6-12 months after the second injection induces a high and long-lasting protection against artificial or natural challenge infections. This review describes work carried out on the formulation, safety and efficacy of the vaccine under laboratory and field conditions, using artificial or natural challenges with E. granulosus eggs, followed by necropsy. Hydatid control programmes based on regular treatment of all dogs with the correct dose of a highly-efficient anthelmintic have sometimes not been successful in Continental environments. Access to dogs is difficult in summer because of the distances to summer pastures, and is often impossible in winter because of snow. A control program using strategic twice-yearly anthelmintic treatment of dogs is likely to be successful provided grazing animals are vaccinated as well. Vaccination as a control tool only requires the veterinarians to visit two times a year, and while the veterinarian is present, the dogs can be treated with anthelmintic for little additional cost. One visit should take place after the autumn kill of animals for winter consumption, and this is a good time to vaccinate animals born in the summer, and also all other animals while they are healthy and immunologically responsive. The other visit should take place in the spring, at which time animals born during winter can be vaccinated. Although a single immunization has been shown to induce a useful degree of protection, where possible it is best to give two initial injections, 1 month apart. If it is possible for veterinarians to stay in the field for 2 months in November/December and March/April, in order to give the two injections, a more rapid onset of full protective immunity will initially be achieved than if the injections are given 6 months apart. A large-scale safety and efficacy trial involving 50,000 and 100,000 lambs in Qinghai and Xinjiang Provinces of China has taken place. Results have confirmed safety and efficacy. In most countries, prevalence of infection increases with age. The vaccine has no effect on established cysts, and therefore, in order to prevent the biomass of Echinococcus spp. from increasing, it might be an effective strategy to begin a control programme by vaccinating all animals. Because many of the older stock will already be infected, they will remain a source of infection for dogs for the average lifetime of the stock. Dogs will still be able to be infected from the older stock, and will continue to infect humans. We advocate that a vaccination programme be accompanied by education about hydatid disease, and anthelmintic treatment of dogs in late autumn and early spring.

Perspective on control options for Echinococcus multilocularis with particular reference to Japan

Following a brief introduction of recent advances in molecular and immunological technology for detection of persons and animals infected with Echinococcus multilocularis and an overview of the current situation of alveolar echinococcosis (AE) in Japan, perspectives on control options are discussed with reference to different epidemiological situations. AE is considered the most serious parasitic zoonosis in temperate and arctic regions of the northern hemisphere. The number of human cases differs drastically among regions. While high numbers of patients are apparently associated with high E. multilocularis prevalence in domestic dogs, e.g. in parts of Alaska and western China, the number of cases is moderate or low in areas where the parasite is mainly transmitted by wild canid species (e.g. in central Europe or temperate North America). However, the severity of the disease, the absence of curative treatment for most cases, the high cost of long-term chemotherapy and the anxiety caused for the population in highly endemic areas call for the development of preventive strategies even in regions where human AE is rare. Furthermore, in view of (1) drastically increasing numbers and infection rates of foxes involved in transmission of E. multilocularis, and (2) increasingly close contact between humans and foxes e.g. in Europe and Japan, there is considerable concern that AE incidences may in future increase in these regions. Control options depend on a variety of factors including the species of canid principally responsible for transmission and the socio-economic situation in the region. Where domestic dogs (stray or owned) are the principal hosts for E. multilocularis, control options can include those applicable to E. granulosus, i.e. reduction of the number of stray dogs, registration and regular preventive chemotherapy of owned dogs, and information campaigns for the population promoting low-risk behaviour for man and dogs. Where E. multilocularis is mainly transmitted by wild canids, the situation is far more difficult with preventive strategies still being in trial stage. Integrated control measures could include prevention information campaigns, restricting access of pet animals (dogs and cats) to rodents, chemotherapy of foxes on local or regional scales, and strategies to minimize contacts between people and foxes.

Cystic echinococcosis and the Mediterranean Region: a long-lasting association

Cystic echinococcosis (CE) is an important zoonosis in Italy and in the whole Mediterranean Region, as confirmed by the work by Ettore Biocca, whose contributions to the subject are reported in a summarised annex to the bibliography. The contribution to the understanding and control of CE are presented, with special emphasis on the socio-economic impact, on factors affecting the maintenance of CE in the Mediterranean Region, on the epidemiological situation and control measures, on the present status of epidemiological surveillance, on the control problems in normal and emergency situations, on health education and training. Also, the justifications of combined control programmes are discussed, which may be applied only in situations of peace and well-being.

Estimating the economic effects of cystic echinococcosis. Part 3: Jordan, a developing country with lower-middle income

The economic costs of cystic echinococcosis (CE) in Jordan, a developing country of lower-middle income, were investigated. Initial cost-estimates for livestock were based on the published prevalences of Echinococcus granulosus infection in sheep and goats and the values of livestock-related products together with likely production losses. Likewise, the annual numbers of human cases of CE were estimated using published surgical incidences in man. The costs of surgery were estimated from hospital records and by costing out the procedures each patient received whilst undergoing treatment. After comparing the quality of life of patients treated for CE with that of case-matched controls, it appeared that the treated patients had some long-term morbidity caused either by the disease or the resulting treatment. A simple spreadsheet model was built up, to sum the individual cost items. Each cost item and each of the data related to prevalence and incidence was assigned a mathematical distribution and varied randomly, using Monte-Carlo techniques, throughout its range, over 10 000 simulations. The results of the study indicate that the most likely range of annual economic losses attributable to CE in Jordan (encompassing 95% confidence limits) is from U.S.$2 602 215-6533 661, with a median of U.S.$3 874 070.

[Extensivity of appearance of echinococcosis among swine in Lublin's voivodship in period 1993-2000]

Aim of the work was presentation of appearance of hydatid among swine in Lublin' s voivodship between 1993-2000. Substance for researches was brought from annual reports inserted into journals of official examination leaded by Veterinary's Inspenction of Sanitation in slaughterhouses. It was proved that average 10,1% of swine on territory of Lublin's voivodship in period 1993-2000 was infected. Frequency of infection among examined animals were the highest in last year of researches 200 and reached 13,4%.

Estimating the economic effects of cystic echinococcosis: Uruguay, a developing country with upper-middle income

Cost-benefit analyses, run before the commencement of a programme to control a parasitic disease, should include estimates of the economic losses attributable to the disease. Uruguay, a middle-income, developing country, has a recent history of persistent problems with cystic echinococcosis, in both its human population and livestock. The economic effects in Uruguay of this disease, caused by the larval stage of the canine tapeworm Echinococcus granulosus, have now been evaluated. Data on the incidence of the disease, in humans and livestock, were used to construct cost estimates. The estimated minimum cost (U.S.$2.9 million/year) was based on the condemnation costs of infected offal together with the actual costs of the hospital treatment of the human cases. The estimate of the maximum cost (U.S.$22.1 million/year) also included the production losses resulting from lower livestock efficiency and the reduced income of individuals with morbidity attributable to the disease.

Hydatidosis: a comprehensive view of the Sardinian case

In Sardinia the close association of sheep, dogs and humans still exists in some parts of the region, so that ideal conditions persist for the perpetuation of the parasite's life cycle. Two factors contribute to the spread of the disease: the practice of slaughtering sheep at home and the proliferation of dogs, mainly strays. This paper reviews the epidemiological picture and the economic consequences of the disease in man and livestock, strongly suggesting that this endemic disease is a major public health problem.

Metacestodes of sheep with special reference to their epidemiological status, pathogenesis and economic implications in Fars Province, Iran

This study was undertaken over a period of 2 years. Of 7992 sheep examined, 2088 (26.12%), 2266 (28.36%), 15 (0.19%) and 738 (9.8%) were infected with Echinococcus granulosus, Taenia hydatigena, Taenia ovis and Taenia multiceps metacestodes, respectively. The prevalence was higher in animals belonging to migratory tribal people than in those owned by the permanent residents of Fars Province. Dogs in the former group also showed significantly higher levels of infection with E. granulosus (33.3%) and Taenia spp. (40.7%) than those in the latter group. The metacestodes caused tissue damage in different organs, resulting in condemnation of meat or viscera valued at 10.2 million rials. The migration of tribal people has a direct bearing on the transmission of these parasites and must be taken into account in control planning.

Some observations on hydatidosis in Jordan

A total of 2.8% (5 of 176) sera from schoolchildren and university students were seropositive for hydatidosis (Echinococcus granulosus), by the ELISA IgE test. The prevalence of seropositivity was 4.5% among females of all age groups (5-24 years) and among males of the age group 18-24 years. Males of the age group (5-17 years) were seronegative. The ratio of seropositivity between schoolboys and schoolgirls was 1:4. Sera collected from 1085 university students, aged 18-24 years, and from 1656 outpatients from northern and central Jordan, and the Jordan River valley, when tested by the IHA test, revealed the presence of anti-hydatid agglutinating antibodies in 5.16% (56 of 1085) and in 3.6% (60 of 1656) respectively, with a male to female infection ratio of 1:3 in the university students and 1:1.1 in the outpatients. Intensity, prevalence and cyst fertility of E. granulosus increased in sheep with age. The results of this study indicate that hydatidosis is in an endemic steady state in Jordan with estimated economic losses of JD 3.0 (= US $4.4) per infected sheep.

[Hydatidosis in the IXth Region of Chile. A regional problem and challenge]

Infection by Echinococcus granulosus is the main zoonosis affecting the human population of the IXth Region in southern Chile. Prevalence rates vary from 18.2 to 48 per 100,000. Animals are affected with prevalence rates of 40% for bovines, 39.5% for sheep and 14.8% for pork as estimated at the central meat processing plant in the city of Temuco. A cost of approximately $300,000 is estimated to treat affected individuals. Much greater losses may be estimated from unnotified meat processing in rural areas and from reduced yield of animal products such as wool an milk. Accordingly, a regional program for control of this zoonosis is urgently required.

Population dynamics in echinococcosis and cysticercosis: economic assessment of control strategies for Echinococcus granulosus, Taenia ovis and T. hydatigena

An official control programme against Echinococcus granulosus and Taenia hydatigena has been in operation in New Zealand for more than 28 years and against Taenia ovis for more than 18 years. This unique effort to control three metazoan parasites at the same time has led to a change from endemic to extinction status for E. granulosus but only a change from hyperendemic to endemic status for T. hydatigena and T. ovis. This has presented problems in determining the most cost-effective future control strategies. To facilitate this, a benefit/cost analysis of 20 options for the combined control of E. granulosus, T. hydatigena and T. ovis in New Zealand was undertaken. This showed that for E. granulosus a future change from the current non-targeted to a targeted approach is strongly indicated. For T. ovis 6 options were cost-effective using a discount rate of 10%. These were (1) a targeted control package using a vaccine in the non-targeted attack phase; (2) a targeted control package using a larvicide in the attack phase; (3) the transfer of all losses due to and responsibility for the control of T. ovis to the producer who administers a larvicide to sheep to be killed for dog food; (4) the transfer of all losses due to and responsibility for the control of T. ovis to the producer who administers praziquantel every 6 weeks to dogs; (5) and (6) two options involving the discontinuation of control. Control of T. hydatigena was assumed to be an incidental outcome of the policies for the other two parasites.

Hydatidosis in Sardinia: review and recommendations

In Sardinia, hydatidosis due to Echinococcus granulosus is endemic and constitutes a current and important problem in the economy and public health. This paper reviews the epidemiological aspects, including the geographical distribution, and the socio-cultural factors involved in the dissemination of hydatidosis. Hospital data indicate that about 200 people undergo surgery for hydatid cysts every year with an average of 8.8 deaths annually. An average of 80% of the sheep are infected, constituting a livestock loss estimated as over 20 billion liras per year. The benefits expected from a hypothetical control programme amount to approximately 32 billion liras against an investment of 17 billion liras in a control programme extending over a period of 10 years. The eradication campaign should result in a gradual reduction of infection rate from 80% to 10% in sheep, from 30% to 3-5% in dogs and in a reduction of human morbidity from 200 to 15 cases, equal to a prevalence rate of 1 per 100,000 inhabitants.

Cost-effectiveness analysis of echinococcosis-hydatidosis eradication project in Sardinia

In this study we attempt to evaluate the convenience of a campaign to eradicate the echinococcosis in Sardinia vs a 'do-nothing' or do-very-little policy adopted at this time. The main conditions which have to be met in setting up the eradication programme are identified as follows: (a) precise knowledge of the real diffusion of the parasitosis in man and animals; (b) eradication project control (action research); (c) health education; (d) reduction of stray canine population; (e) anthelmintics distribution and permanent health control to registered dogs. In Italy, echinococcosis-hydatidosis is present in many regions but in none has reached the diffusion rate present in Sardinia where over 200 patients per year are surgically treated, with a prevalence rate of 13.32 per 100,000 inhabitants. The disease does not spare any social or age group. The economic aspects of hydatidosis involve losses due both to human and to livestock resources, evaluated in monetary or non-monetary terms, according to circumstances. As a method to evaluate the human life has been assumed the years gained related to the Potential Years of Life Lost (PYLL). Several Net Present Values (NPV) have been calculated under alternative discount rates inclusive of the Internal Rate of Return (IRR).