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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.

Since its introduction more than 20 years ago, ivermectin has proved to be one of the most successful therapeutic drugs in veterinary medicine, as well as the basis of one of the most successful public-health programmes of the past century. The drug arose from a unique international collaboration between the public and private sectors. The development process also incorporated the world's first and largest drug-donation programme and involved a unique association between governments, non-governmental organizations and industry. The drug is now being used, free of charge, in two global disease-elimination programmes that are benefiting millions of the world's poorest people.

The presumptive treatment of parasitosis among immigrants with albendazole has been shown to save both money and lives, primarily via a reduction in the burden of Strongyloides stercoralis. Ivermectin is more effective than albendazole, but is also more expensive. This coupled with confusion surrounding the cost-effectiveness of guiding therapy based on eosinophil counts has led to disparate practices. We used the newly arrived year 2000 immigrant population as a hypothetical cohort in a decision analysis model to examine the cost-effectiveness of various interventions to reduce parasitosis among immigrants. When the prevalence of S. stercoralis is greater than 2%, the incremental cost-effectiveness ratios of all presumptive treatment strategies were similar. Ivermectin is associated with an incremental cost-effectiveness ratio of 1700 dollars per QALY gained for treatment with 12 mg ivermectin relative to 5 days of albendazole when the prevalence is 10%. Any presumptive treatment strategy is cost-effective when compared with most common medical interventions.

Previous surveys in Myanmar indicate that soil-transmitted helminths (STH) are a significant public health problem. However the majority of these surveys are small scale or hospital based. To date there has been no countrywide assessment of the prevalence and intensity of STH infection. We conducted a survey (June 2002-June 2003) to assess the magnitude of STH infection in school age children in each of the different ecological areas of the country. In each area, five schools were selected and from each one, 50 children were randomly chosen. Parasitological and nutritional data were collected from each child. We found an overall prevalence of infection of 69%: 18% had a moderate-heavy intensity of infection, 22% were anaemic. A pilot exercise to treat 25,000 school age children in the 200 schools of Nyangdone Township tested the strategy before scaling up and to generate some rough costings. A crude calculation of the expenditure to buy and deliver the drugs, including the costs incurred in the teacher training, concluded that the cost per child was approximately 0.05 USD.

Infection with Ascaris lumbricoides constitutes one of the most common helmintic diseases in the world, especially in tropical and subtropical regions. Transmission of this disease involves environmental contamination with eggs, and therefore, is classified as a soil-transmitted disease. The public health importance of ascariasis is made evident by the high number of infected individuals suffering its consequences, which can become severe, depending on the worm burden. Since the introduction of benzimidazoles, chemotherapy has improved significantly, offering fast and direct effects at relatively low cost, as a result of the simple and safe application of these drugs. Unfortunately, the effects are not long-lasting or permanent. The intervention with chemotherapy alone constitutes a fast and efficient way to reduce the worm burden in a population of high prevalence, but does not avoid reinfection. Therefore, the option of integrated control programmes based on chemotherapy in combination with sanitation and health education, together with strong community involvement, must be considered in order to ensure the positive long-term effects of such programmes.

Worm control practices and anthelmintic usage in 177 cattle farms in Iringa district in the southern highlands of Tanzania was determined through a questionnaire survey. A total of 76 traditional, 92 small-scale dairy and 9 large-scale dairy cattle farms were included in the survey. Results indicated that 87.7% traditional, 97.8% small-scale dairy and 100% large-scale farmers relied solely on the use of anthelmintics, 2.7% traditional farmers used traditional medicines while 9.6% traditional farmers had not any form of worm control practice. Worm infection was ranked the second most important constraint of productivity in cattle in the three production systems. Most farms (57.6% traditional, 35.8% small-scale dairy, 66.7% large-scale dairy) used anthelmintics with a combination of levamisole and oxyclozanide. Benzimidazoles were used only in traditional (25.4%) and small-scale dairy (32.1%) farms while nitroxynil (Trodax) was mostly used in large-scale dairy farms (33.3%). Generally, 40% of farmers treated three or four times a year and the frequency in some farms was surprisingly high for resource poor small-scale farmers. The frequency of anthelmintic treatment was mostly the same regardless of the management system. Treatments in most farms depended on availability of money and drugs and not the epidemiology of parasites. A significant proportion (46.3%, P=0.007) of farmers especially in rural areas failed to follow their pre-planned treatment schedules due to lack of money (86%) and unavailability of drugs (6.6%). Many farmers (58.9%) had used the same type of anthelmintic for four or more consecutive years and 85.3% of them would continue with the same anthelmintic. Farmers in all management systems mostly purchased anthelmintics from private veterinary drug shops and about 43% traditional and 33.3% small-scale dairy farmers mostly in rural areas obtained anthelmintics from village extension officers. Despite the fact that all farmers were aware of worm infection and the associated signs in cattle, 42.5% had poor knowledge on the source of worm infection. Small-scale dairy farmers allowed only a 1-day withdraw period for milk regardless of the type of anthelmintic used and there was no milk and slaughter clearance in traditional farms. It was concluded from this study that worm control in Iringa faces serious constrains and that education of farmers and farm hands is not adequate. Moreover, poor quality control and high price of potent anthelmintics, few extension workers, low income and low education among farmers contributed significantly to erratic worm control practices and anthelmintic usage in peri-urban and rural areas.

An essential component of any helminth control programme is its monitoring and evaluation. These activities provide opportunities to adjust programme implementation, to resolve issues that are problematic, to reinforce personnel satisfaction, to ensure programme quality, and to document the impact of the programme on health and other outcomes. A set of core indicators is proposed to be able to compare the impact of control programmes in different jurisdictions or countries. By ensuring regular programme performance appraisal through monitoring and evaluation activities, future programme implementation can be sustained and cost-effectiveness can be optimized.

In October 2000, 71,187 persons were treated for lymphatic filariasis using albendazole and diethylcarbamazine (DEC) or DEC alone in Leogane, Haiti. We documented the frequency of adverse reactions, severity and cost of treatment. Adverse reactions were classified as minor, moderate, or severe. Overall, 24% (17,421) of the treated persons reported one or more adverse reactions. There were 15,916 (91%) minor and 1502 (9%) moderate adverse reaction reports. Men outnumbered women 2:1 in reporting moderate problems. Three patients, representing roughly one in 25,000 persons treated, were hospitalized with severe adverse reactions judged to be treatment-associated by physician review. The cost per person treated for adverse reactions was more than twice the cost per person treated for lymphatic filariasis (dollar 1.60 versus dollar 0.71). Severe adverse reactions to lymphatic filariasis treatment using DEC with or without albendazole are uncommon. Minor and moderate reactions are more commonly reported and their management represents a challenge to lymphatic filariasis elimination programs.

Large-scale chemotherapy programmes for helminth control continue to rely heavily on donor support. This is despite more than a 10-fold reduction in delivery costs from integrating drug distribution through the school system rather than using mobile teams and a marked decline in the price of albendazole and praziquantel. Even at these low prices (

An essential component of integrated schistosomiasis control as promoted by WHO is adequate clinical care for patients presenting at health care facilities. We evaluated the functioning of the Ghanaian health system for diagnosis and treatment of schistosomiasis by interviewing health workers from 70 health care facilities in 4 geographical areas in April and May 2000. Results from presentation of 4 hypothetical cases and a subsequent interview demonstrated that patients presenting with symptoms related to schistosomiasis have a small chance of receiving adequate treatment: often health workers do not recognize the symptoms, especially those of Schistosoma mansoni; patients are frequently referred for a diagnostic test or treatment with a large risk of non-compliance; and praziquantel was not available in 78% of the health care facilities with reported schistosomiasis in their coverage area. The overall cost of treatment is considerable: [symbol: see text] 2.13 for S. haematobium and [symbol: see text] 1.81 for S. mansoni patients, with drug costs contributing approximately 40% of the total cost. To better meet WHO recommendations for passive case detection as part of integrated schistosomiasis control, the Ghanaian health system needs to emphasize training of health workers in schistosomiasis case recognition and case management and increase the availability of praziquantel. Experience from other West African countries indicate that this is feasible.

Objectives: To determine the start-up processes, costs and consequences of community-directed treatment with ivermectin (CDTI) in two onchocerciasis endemic rural towns of Southeast Nigeria; namely Achi and Nike. The other objectives were to discover the community-financing mechanisms, local ivermectin distribution strategies and communities' organisational capacity to handle the programme., Methods: Structured questionnaires, informal interviews, observations, discussions with community members at general village assemblies and community outreach lectures were used at different stages of the study., Result: The towns had the organisational capacity to implement the programme. Coverage with ivermectin was between 31-73% in Achi (mean = 58.6%), and 36.6-72% in Nike (mean = 61.95%). The unit financial costs were $0.17 in Nike and $0.13 in Achi, but the unit aggregate cost was $0.37 in Nike and $0.39 in Achi. When research costs were removed, the unit aggregate cost was $0.22 in Achi and $0.20 in Nike. Provider's financial costs and communities' non-financial costs were the biggest contributors to the aggregate cost. The cost would decrease in subsequent years since the research cost and parts of the mobilisation and training costs would not be incurred after the first year., Conclusion: Governments and sponsors of CDTI should find means of continuously strengthening the programme and providing technical support to the communities. As both CDTI and communities are dynamic entities, continuous health education campaigns are needed to keep reminding the people of the benefit of long-term ivermectin distribution, together with the need for community ownership of the programme.

A study was carried out in 8 villages endemic with S. japonicum in Hunan Province, China from 1998 to 2000 to evaluate the cost-effectiveness in preventing schistosome infection and related morbidity under three chemotherapy schemes: (1) 'clue' chemotherapy, consisting of treatment to those with contact with infected water and/or symptoms of infection; (2) 'mass' chemotherapy-treatment to all the villagers except those not able to take praziquantel; and (3) 'screen' chemotherapy-treatment prescribed to the stool egg positive cases after Kato-Katz examination. An itemized cost menu was used to estimate the cost incurred to each scheme, from the perspective of the health care provider. The numbers of cases prevented by chemotherapy schemes were estimated through standardized attributable fractions of the outcomes to absence of chemotherapy before intervention. The cost-effectiveness ratios were calculated using weighted ranks of unit costs of the four outcome measurements: the costs per case with infection, liver and spleen abnormality (as determined by ultrasonography) prevented and 1% reduction in intensity of infection (as estimated by egg per gram feces, EPG) after the two years of intervention. Sensitivity of total cost to changes in the costs of personnel, praziquantel and other key factors were analyzed. It is demonstrated that all the three schemes had a significant impacts on the prevalence and intensity of infection, but the overall effects on liver and spleen morbidity of the residents varied between schemes. Mass chemotherapy achieved the best cost-effectiveness ratio, with unit costs of preventing cases of infection, liver and spleen abnormality and 1% reduction of EPG being RMB yuan 161.2, 99.8, 219.3 and 176.3, respectively. However, clue and screen chemotherapy schemes did not show significant prevention of liver damages in the villagers. The unit costs per case prevented for the outcomes were RMB yuan 140.2, 602.7 and 169.3, respectively for clue chemotherapy, while RMB yuan 190.0, 448.4 and 145.0 respectively for screen chemotherapy. The study concluded that mass chemotherapy should still be the choice of preference in areas where prevalence of infection and frequencies of contact with infested water by residents are high, particularly if the drug cost could be further reduced. Clue chemotherapy could be an alternative to mass chemotherapy, especially when the frequency of water contact is not as high as 80% recorded in our study. Screen chemotherapy is the least favored option in the hyperendemic area of Hunan Province.

A telephone survey was conducted of the methods used to control parasitic worms at 106 thoroughbred training yards. Most of the horses were allowed access to grass and were therefore at risk of infection. The control methods relied primarily on the use of anthelmintics and appeared reasonably successful because only 44 per cent of trainers reported observing clinical signs of nematode infections. They dosed their horses frequently, 40 per cent treating every four to six weeks and 25 per cent treating every seven to eight weeks. New arrivals on yards were usually treated with anthelmintic but the strategies used would be unlikely to prevent the introduction of anthelmintic-resistant nematodes on most yards or to deal with encysted cyathostomes. Trainers were responsible for the design of most control schemes, and only 42 per cent of them based their choice of anthelmintic on veterinary advice.

The effectiveness of the treatment of neurocysticercosis with praziquantel has been assessed in several clinical trials in the last 20 years. Most studies employed a dose of 50 mg/kg/day, three times at day during 2 weeks. Recently, a novel and brief dosage scheme of praziquantel has been described. This scheme employs three doses of 25 mg/kg, and all are administered separately on the same day, with interval of 2 hours. This scheme has a direct impact on direct costs (cost of drugs), with a 90% reduction of the traditional scheme. In addition to a favorable impact on direct costs, the impact on indirect costs is important: with the short-scheme, hospitalization in unnecessary, and costs of hospital visits for patient and family is avoided, with subsequent improvement of emotional status and family environment.

Background: A project to improve integrated control of schistosomiasis in the primary health care system of northern Senegal was implemented from February 1995 until September 1999, shortly after a Schistosoma mansoni outbreak. The activities included additional training of doctors and nurses in symptom-based treatment and making praziquantel (PZQ) available for an affordable price., Objective: To investigate staff performance and the availability and costs of diagnostic materials and PZQ at the end of this intervention project., Methods: We performed structured interviews with staff from 55 health care facilities in five districts., Results: Respondents from 23 health care facilities reported both S. haematobium and S. mansoni in the coverage area, 32 reported only S. haematobium and three only S. mansoni. The average cost to patients for consultation, diagnosis, treatment and transportation to a referral health care facility was approximately 1.60 Euro. Fifty-seven per cent of the health care facilities with reported S. haematobium in the coverage area treated patients presenting with haematuria on symptoms; 56% of the health care facilities with reported S. mansoni in the coverage area treated patients presenting with blood in stool on symptoms. Thirteen per cent performed a diagnostic test for patients presenting with haematuria and 12% for patients presenting with blood in stool. The remainder, approximately one-third of the health care facilities, referred their patients to another facility for a diagnostic test. Implementation of symptom-based treatment in all health care facilities will reduce the total costs by 0.43 Euro (29%) for patients infected with S. haematobium and 0.78 Euro (46%) for patients infected with S. mansoni. Of the 53 health care facilities with schistosomiasis in their area, 37 had PZQ in stock of which 33 (88%) sold PZQ for the recommended retail price of 0.15 Euro per tablet (or 0.60 Euro per course of four tablets) or lower., Conclusion: Four years after the start of the intervention project, patients presenting with schistosomiasis related symptoms can generally expect proper diagnosis and treatment at all levels of the health care system in Northern Senegal, either at the initial visited health care facility or after referral. However, a further reduction of the total costs of treatment is still possible by a better implementation of symptom-based treatment and further reduction of the costs of PZQ.

Poor people in developing countries endure the burden of disease caused by four common species of soil-transmitted nematode that inhabit the gastrointestinal tract. Disease accompanying these infections is manifested mainly as nutritional disturbance, with the differing infections having their deleterious effects at different phases during the human life cycle. Reduced food intake, impaired digestion, malabsorption, and poor growth rate are frequently observed in children suffering from ascariasis and trichuriasis. Poor iron status and iron deficiency anemia are the hallmarks of hookworm disease. The course and outcome of pregnancy, growth, and development during childhood and the extent of worker productivity are diminished during hookworm disease. Less is known about the impact of these infections in children under 2 years of age. The severity of disease caused by soil-transmitted nematodes has consistently been found to depend on the number of worms present per person. Cost-effective measures based on highly efficacious anthelminthic drugs are now available to reduce and control disease caused by these infections.

To understand the rationale behind recommended control programs for liver flukes in cattle, the economic impact and the complex life cycle of Fasciola hepatica need to be appreciated. Fluke-infected cattle rarely demonstrate clinical disease, but subclinical impairment of feed efficiency, growth, and fertility can have an important impact on productivity. Although the precise benefit from controlling liver flukes is unknown due to the inherent variability between studies, most investigations demonstrate a considerable economic advantage to treatment. In addition, recent studies have demonstrated that liver flukes may cause a decrease in host fertility by altering normal metabolism and/or balance of sex hormones. This review focuses on these issues and how to best use available drugs to implement optimal fluke control programs.

This paper presents the results of an evaluation of community perception of two large-scale, government-run, school-based health programmes delivering anthelmintic drugs to primary school children, in Ghana (80 442 children in 577 schools) and Tanzania (110 000 children in 352 schools). Most teachers (96% in Ghana and 98% in Tanzania) were positive about their role in the programme, including administration of anthelmintic drugs, and parents and children fully accepted their taking on this role. The benefits of the programme were apparent to teachers, parents and children in terms of improved health and well-being of the children. Over 90% of parents in both Ghana and Tanzania indicated a willingness to pay for the continuation of drug treatment. The evaluation also highlighted areas that are critical to programme effectiveness, such as communication between schools and parents, the issue of collaboration between the health and education sectors, parents' perception of the importance of helminth infection as a serious and chronic health problem (compared with more acute and life threatening illnesses such as malaria), and who should pay for treatment of side-effects.

Current evidence suggests research in veterinary parasitology is in decline despite its importance. This is particularly true in the UK where research funds have been diverted into BSE. Decline in interest in veterinary parasitology is at least in part due to the success of major pharmaceutical companies in producing a range of effective and safe anti-parasitic drugs. Research is needed because of the effects of parasites on animal welfare and the economic costs of parasites. However, there is little information on the actual costs of animal parasites. Another major reason for research is the development of drug resistance in protozoa, helminths and arthropods of veterinary importance. This is a serious problem particularly for sheep and goats in the southern hemisphere. A prioritised list of research requirements is suggested: (i) new drugs; (ii) resistance management; (iii) vaccines; (iv) breeding for resistance; (v) improved diagnostics; (vi) zoonoses; (vii) global warming and parasites. There is a major political challenge to raise the profile of veterinary parasitology and thus the funding essential for its advancement and the continued welfare and productivity of animals.

School health programmes are the basis of the strategy defined by WHO to reduce morbidity due to soil-transmitted nematodes and schistosomes in school age populations in developing countries. However, low rates of school enrollment can be a major factor limiting their success. In the present study enrolled children were informed by teachers on the date of the next deworming campaign and were invited to pass along this information to parents, siblings and friends of school-age. On the day of the deworming campaign, teachers were instructed to administer anthelminthics to enrolled and not enrolled school-age children present at school. In the month following the treatment day, information about coverage was collected by questionnaire in 257 households in two regions of Unguja Island, Zanzibar. Over 89% of school age children resulted treated (98.9% of those enrolled plus 60% of those not enrolled). The additional cost of treating non-enrolled is limited to the cost of providing additional doses of anthelminthic drug in each school. Non-enrolled school age children can easily, successfully and inexpensively included in school based deworming campaign. Managers of control programmes are invited to test this method adapting it in their particular and cultural environment.

Data on reproduction and mortality were collected over one year from 5100 sheep and 13,300 goats in treated and control flocks. The treated animals received vaccination against peste des petits ruminants (PPR) and anthelmintics twice a year. Productivity parameters (fecundity and mortality rates) obtained with and without prophylaxis were fitted into a benefit-cost economic analysis model and run for project lifespans varying from one to five years. At a 7% discount rate, the overall benefits for a project lifespan of five years were estimated as over 15 million FCFA and 11 million FCFA for sheep and goats, respectively. The benefit-cost ratio ranged from 2.26 to 3.27 in goats and 3.01 to 4.23 in sheep, depending on the project lifespan. It was concluded that PPR and gastrointestinal helminthosis are important causes of economic losses in small ruminants in Cameroon. A national or even a regional vaccination campaign against PPR and strategic anthelmintic treatment of small ruminants are recommended.

A seasonal population-dynamics matrix model (periodic Leslie-matrix model) was developed to model short production cycles and high seasonal variations occurring in demographic rates and offtake patterns for small ruminants. The year was split into 24- and 15-day phases. Population-size changes were modelled by the recurrence equation x(j+1)=B(j)x(j), where j was the 15-day phase, x an age-class population size vector and B a fecundity-, mortality-, offtake- and intake-rate matrix. Given an initial vector x(1), annual dynamics were described by x(25)=B(24)...B(1)x(1)=Ax(1), where A was the annual projection matrix.A steady-state hypothesis was used to estimate offtake gains and financial returns from a trial of pasteurellosis vaccination and anthelminthic drench in traditionally managed sheep flocks in Senegal, from July 1987 to June 1988. Nineteen villages and 76 herds were involved in the experiment. Villages were randomly allocated to one of the four treatment combinations in a factorial design, and subsequent demographic rates and net offtake patterns were measured. In the trial, vaccination had a negative effect on offtakes among females. No vaccination effect was observed for males. A positive effect of deworming was found for both sexes. From the trial data, our model calculated that the overall ratio of offtakes (i.e. number of animals) for dewormed over undrenched sheep was 1.2 (95% confidence interval: 1.1, 1.4). The deworming financial benefit-cost ratio was 3.7 (1.9, 5.4).

Schistosomiasis still constitutes a major public health problem in some endemic parts of rural Egypt, particularly in school-aged children. The school-based health programme for schistosomiasis control adopted by the Egyptian Ministry of Health and Population (MOHP) focuses on treating enrolled schoolchildren. Children who are not enrolled or who do not attend regularly (out-of-school) do not have access to this service, in spite of evidence that the prevalence and intensity of infection are higher in these children than among children who attend school regularly. The aim of the present study was to test an intervention to extend the existing routinely applied school-based treatment to the out-of-school children. This paper reports on the costs and the coverage obtained by the intervention under 2 alternative delivery strategies: selective versus mass chemotherapy for out-of-school children. The intervention reached 88.5% of the out-of-school children at a relatively low cost per infected child of 2.29 L.E. (US$0.67) and 2.02 L.E. (US$0.59) for selective and mass chemotherapy, respectively. The calculations also suggest that, if the government were to implement such a programme, it would be more efficient to offer mass than selective chemotherapy at observed levels of prevalence. Sensitivity analysis showed that selective chemotherapy would be more cost-effective in areas where the prevalence of infection in out-of-school children was < 43%.

Numerous studies have shown that anthelminthic treatment can be effective in improving growth rates when given to malnourished children with ascariasis. Recent investigations have also indicated that Ascaris infections can affect mental processing in some school children. Poor socio-economic conditions are among the key factors linked with higher prevalences of ascariasis, as are defaecation practices, geophagia, cultural differences relating to personal and food hygiene, occupational necessity, agricultural factors, housing style, social class and gender. Chemotherapy is currently the major tool used for the strategic control of ascariasis as a short-term goal. In the long term, improvements in hygiene and sanitation are thought to aid long-term control considerably. Targeted treatment, especially when aimed at schoolchildren, has been a major focus of recent control efforts in some areas. Universal treatment reaches more people and thus decreases further aggregate morbidity, especially in nutritionally vulnerable preschool-age children. Selective treatment requires technical effort to identify heavily infected individuals; acceptance by the community may vary in less educated populations when some individuals receive treatment and others do not. Child-targeted treatment may be more cost-effective than population treatment in reducing the number of disease cases and, in high transmission areas, expanding coverage of a population can be a more cost-effective strategy than increasing the frequency of treatment.

Objective: To study the clinical efficacy and the incremental cost-effectiveness of albendazole in improving the nutritional status of pre-school children., Design: Single blind, placebo-controlled trial with child as the unit of randomization., Setting: In the Anganwadi centers of the Integrated Child Development Services situated in the urban slums of Lucknow, North India., Methods: Thirty-two Anganwadi centers were randomly selected for the trial. Included were registered resident children between 1.5 to 3.5 years of age with informed and written parental consent. The intervention group received 600 mg of albendazole powder every six months while the placebo group received same quantity of calcium powder. Enrolled children were contacted once in six months from January 1995 to 1997 and given treatment. The outcome measure were change in the proportion of underweight (weight for age <-2.00z), stunted (height for age <-2.00z) children and the cost per child prevented from becoming stunted., Results: There were 610 and 451 children in the albendazole and placebo groups, respectively. Mean age at recruitment was 31.8 months (SD: 9.7). Follow-up and compliance in both the groups was >95%. During the 2 year follow-up, the proportion of stunted children increased by 11.44% and 2.06% in the placebo and albendazole groups, respectively, and the difference was 9.38% (95% CI 6.01% to 12.75%; p value <0.0001). Direct fecal smear was positive for the ova of ascaris in 41.2% and 55.3% children in the albendazole and placebo groups, respectively at the end of the study (p value <0.001). The annual family expenditure on illness in the recruited child was Rs. 743 (SD: 662) and Rs. 625 (SD: 609) in the albendazole and the placebo groups, respectively. The incremental cost-effectiveness ratio was Rs 543.00 for each case of stunting prevented with albendazole. There was no difference in the various morbidity or cognitive performance, as judged by the revised Denver prescreening questionnaire, in both the groups at enrollment as well as at the end of the study., Conclusions: Six monthly albendazole reduces the risk of stunting with a small increase in the expenditure on health care from the payer's perspective. Larger trials are needed to study the effect of albendazole on prevention of stunting, cognitive functions and all-cause childhood mortality.

It has been argued that the delivery of anthelmintics to school-children through existing education infrastructure can be one of the most cost-effective approaches to controlling parasitic worm infection. This paper examines the actual costs of a combination of mass and selective treatment for schistosomiasis using praziquantel and mass treatment for intestinal nematodes using albendazole, as an integral part of school health programmes reaching 80442 pupils in 577 schools in Volta Region, Ghana, and reaching 109099 pupils in 350 schools in Tanga Region, Tanzania. The analysis shows that financial delivery costs per child treated using praziquantel, which involved a dose related to body mass and a prior screening at the school level, were US$ 0.67 in Ghana and US$ 0.21 in Tanzania, while the delivery costs for albendazole, which was given as a fixed dose to all children, were US$ 0.04 in Ghana and US$ 0.03 in Tanzania. The higher unit costs in Ghana reflect the epidemiology of infection; overall, fixed costs were similar in both countries, but fewer children required treatment in Ghana. Analysis of economic costs-which includes the cost of unpaid days of labour--indicates that the financial costs are increased in Ghana by 78% and in Tanzania by 44%. It is these additional costs which are avoided by integration into an existing infrastructure. It is concluded that: the base cost of delivering a universal, standard, school-based health intervention can be as low as US$ 0.03 per child treated; that even a slight increase in the complexity of delivery can have a significant impact on the cost of intervention; and that the use of the education infrastructure does indeed offer significant savings in delivery costs.

The study examined the cost effectiveness of 4 different regimens in reducing the prevalence and intensity of infection of Ascaris lumbricoides, Trichuris trichiura, and hookworm over an 18-mo period in randomized community samples of children aged 2-8 yr living in rural Bangladesh. The household was the unit of randomization in each community. The 4 regimens were (1) only chemotherapy to all household members at the commencement of the study (i.e., at an interval of 18 mo), (2) same as group (1) and regular health education throughout the study period, (3) chemotherapy to all household members at the commencement of the study and subsequent chemotherapy to all children at intervals of 6 mo, and (4) same as group 3 with the addition of regular health education throughout the study period. Health education (through home and school visits and focus group discussions) was aimed at increasing awareness of worm transmission and the disabilities caused by intestinal helminths. Simple ways of improving personal hygiene and sanitation through hand washing, nail trimming, wearing of shoes, and use of a latrine and clean water supplies were encouraged. Because albendazole is a broad spectrum anthelmintic, the cost effectiveness of the 4 interventions were compared by the weighted percentage reduction in prevalence and the weighted percentage reduction in intensities of infection as measured by geometric mean egg loads of all 3 worms combined. The most cost-effective strategy was the single albendazole mass chemotherapy at an interval of 18 mo. The 2 regimens involving health education were the least cost effective.

It has been argued that targeting delivery of anthelmintics to school-children by taking advantage of the existing education infrastructure and administrative system can be one of the most cost-effective approaches in minimizing the intensity of infections with both schistosomiasis and major intestinal nematodes in many developing countries. The study was conducted in January 1997, shortly after the completion of the drug intervention programme. This paper provides an analysis of the costs of providing age-targeted treatment of school-children for urinary schistosomiasis using praziquantel and for intestinal nematodes using albendazole as an integral part of the School Health Programme in Tanga Region, Tanzania. The analysis shows that the total financial cost of the intervention programme in 1996 prices was US$54 252.28 (exchange rate: TSH 573 = US$1). Of this amount, the cost of drugs constitutes 80.6%, while the delivery cost appears relatively low, representing just below 20%. Even when the opportunity cost of unpaid days of labour input is included, the cost of drugs still remains the highest cost component of the intervention (55.8%). In the current epidemiological and logistic setting of Tanzania, the financial cost per child treated using praziquantel, which involved prior screening at the school level, was US$0.79, while treatment using albendazole was as low as US$0.23, of which US$0.20 was drug purchase cost. It is concluded that the base cost of delivering a universal, standard, school-based health intervention such as albendazole can be as low as US$0.03 per child tested, but even a very slight increase in the complexity of delivery can have a very significant impact on the cost of intervention.

This article analyzes policies that affected the availability of praziquantel, the drug of choice for schistosomiasis. The study examines how interactions among four actors (pharmaceutical producers, international agencies, non-governmental agencies, and national governments) affected praziquantel availability in poor countries. It also examines trends in praziquantel prices over time in different markets. This analysis demonstrates that the discovery of an effective new drug does not necessarily result in access to the drug for disease sufferers--especially if those sufferers are poor people in poor countries. The article proposes measures to improve international systems for making new drugs available in poor countries.

Understandably, cattle are raised for profit, as beef and/or dairy. Anything that negates that equation results in a loss to the producer and to the livestock economy. Thus, parasites negatively affect the economy of the industry. Worldwide, gastrointestinal nematode parasites, especially Ostertagia ostertagi, and those of the respiratory tract (Dictyocaulus viviparus) have a potentially major impact on herd health. In the past 10-15 years, anthelmintic (AH) drug development and the strategic use of AH have positively balanced the economic equation, so that overall, parasitism in cattle is often observed or determined to be subclinical or economical. Other control measures, such as better pasture management, are also being developed to enhance herd health and the cattle economy. The determination of the economic impact of parasitism has thus become less apparent, to the extent that measures, such as performance parameters, must be used to measure differences between treated and untreated animals or herds. These include weight gain, reproduction, lactation and forage use. To determine the effectiveness of control measures, field trials are designed to measure these parameters by the demonstration of improved performance. Because these trials are conducted in a competitive mode, results are often debated by competitors and by the scientific community because of study design. Variables must then be taken into consideration in the interpretation of results. It is now well known that, with the generation of new AH and appropriately-timed administration, parasitism of well-managed herds has been reduced to subclinical levels. Thus, we are now in the process of fine-tuning the positive effect of these control measures for enhanced production. Understandably, beef and dairy producers have 'production of high quality commodities' at a cost-effective level as a common goal. Successful cattlemen calculate expenditures and income by line item including veterinary expenses and cost and labor in administration of AH. Return is based on performance. Again, nematode parasites can disturb the equation enough to make production less profitable or even unprofitable. Most USA beef cattle producers believe that worm parasites do have an effect on cattle health and production so that 77% use AH and the market impact is that AH have become integrated into cattle herd health programs. However, to be most cost-effective, programs must be strategic but flexible with scheduling tailored for the region and the cattle operation. Other technologies should eventually provide rapid identification of worm populations by species and numbers and recognition of individual animal response to parasites and inheritance of that trait by their progeny. Computerized programs for analysis of seasonality of the epidemiology of gastrointestinal parasites and of herd performance could predict appropriate timing and cost benefit for control measures. Modes of AH administration are being developed which are more reliable and convenient in terms of delivery and labor. Control measures must also include better pasture management with less impact on the environment and to justify investment in land. In addition, successful producers are better educated, more cost-conscious, consumer-oriented, sensitive to the environment and attuned to the economics of parasitism.

A large-scale study was undertaken to investigate the effects of two systematic anthelmintic treatments on village cattle productivity in the Gambia. Treated animals had significantly higher performance in terms of live weights and age at first calving, but the mortality rate of 0- to 1-yr-old cattle appeared to be negatively affected. These results and financial data on treatment costs were used in a herd simulation model to assess the profitability of the intervention. Treatment was profitable on average, but the risks of losing money were large and average returns were sensitive to various hypotheses examined. The treatment regimen studied can only be recommended in certain herds and further research is needed to identify the factors determining the negative response in other herds.

This article reviews the principles involved in establishing the cost effectiveness of mass drug therapy for the major intestinal nematodes and the intestinal form of schistosomiasis, as well as the extent to which the available studies have provided definitive answers. For governments or agencies that have decided to introduce a control programme, there is considerable evidence about the comparative cost effectiveness of different types of delivery strategies. For example, mass treatment is more cost effective than selective treatment (treatment after individual screening) in high prevalence areas and at observed prices. Mass treatment targeted at known high risk groups, such as schoolchildren, for the major intestinal helminths (apart from hookworm) can be more cost effective than population-based mass treatment. However, this raises the question whether any form of mass anthelmintic chemotherapy is an efficient use of scare health resources in view of the competing demands for scarce public funds, and for the scarce resources of other funders of healthcare including donors, nongovernmental organisations and missions. Some evidence that it is an efficient use of resources is available; this article concludes by outlining the type of information that is required to strengthen the argument for mass therapy.

In the Swellendam area, benzimidazoles held 34.5% of the market for sheep and goat nematocides in 1988, ivermectin 30.1%, levamisole 13.7%, combination products 13.5%, salicylanilides 6.8% and morantel 1.4%, while products containing benzimidazole accounted for 48.1% of sheep and goat nematocide sales. The sheep and goat nematocide and cestocide markets in the Swellendam area totalled 1,386,280 and 94,080 therapeutic doses respectively, costing R448 887,10 and R79 242,02, while the cattle anthelmintic market totalled 12,209 therapeutic doses, costing R30 520,22. A mean of 3.45 therapeutic doses of nematocide were purchased for sheep and goats during 1988 at a per capita cost of R1.12 at December 1988 prices. Furthermore, the mean per capita expenditure on anthelmintics against both the nematodes and cestodes of these animals, amounted to R1.31. Nematocides used for sheep and goats in this market segment, cost 36 cents per dose. The mean escalation of anthelmintic prices between January and December 1988 was 10%, ranging from -6 to 30%.