Control of Ascaris infection by chemotherapy: which is the most cost-effective option?

Cost-effectiveness analysis is used to predict the optimal design of mass chemotherapy strategies in controlling Ascaris lumbricoides infection. The question of who to treat, how many to treat, and how often to treat are addressed using a population dynamic model of helminth transmission that assesses effectiveness in terms of disease reduction, combined with cost data from an actual control programme. Child-targeted treatment can be more cost-effective than population treatment in reducing the number of disease cases. The model also implies that, in the circumstances described here, enhancing coverage is a more cost-effective approach than increasing frequency of treatmen

Evaluation of efficacy of school-based anthelmintic treatments against anaemia in children in the United Republic of Tanzania

Objective: To determine the impact of deworming on anaemia as part of a large-scale school-based anthelmintic treatment programme in the Tanga Region of the United Republic of Tanzania. Methods: Both the reduction in the prevalence of anaemia and the cost per case prevented were taken into consideration. Cross-sectional studies involved parasitological examination and anaemia evaluation before and at 10 months and 15 months after schoolchildren were dewormed. Findings: Baseline studies indicated that the prevalence of anaemia (haemoglobin < 110 g/l) was high (54%) among schoolchildren, particularly those with high intensities of hookworm and schistosomiasis. Attributable fraction analysis suggested that hookworm and schistosomiasis were responsible for 6% and 15% of anaemia cases, respectively. Fifteen months after deworming with albendazole and praziquantel the prevalence of anaemia was reduced by a quarter and that of moderate-to-severe anaemia (haemoglobin <90 g/l) was reduced by nearly a half. The delivery of these anthelmintics through the school system was achieved at the relatively low cost of US$1 per treated child. The cost per anaemia case prevented by deworming schoolchildren was in the range US$ 6 - 8, depending on the haemoglobin threshold used. Conclusions: The results suggested that deworming programmes should be included in public health strategies for the control of anaemia in schoolchildren where there are high prevalences of hookworm and schistosomiasis

Effect on weight gain of routinely giving albendazole to preschool children during child health days in Uganda: cluster randomised controlled trial

Objective: To estimate the effectiveness of delivering an anthelmintic through a community child health programme on the weight gain of preschool children in Uganda. Design: Cluster randomised controlled trial. Setting: Eastern Uganda. Participants: 48 parishes participating in a new programme for child health: 24 offered children an additional service of anthelmintic treatment. The outcome is based on measurements from 27 995 children. Intervention: Treatment of children aged between 1 and 7 years with 400 mg albendazole added to standard services offered during child health days over a three year period. Main outcome measure Weight gain. Results: The provision of periodic anthelmintic treatment as a part of child health services in Uganda resulted in an increase in weight gain of about 10% (166 g per child per year, 95% confidence interval 16 to 316) above expected weight gain when treatments were given twice a year, and an increase of 5% when the treatment was given annually. Conclusion: Deworming of preschool children in Uganda as part of regularly scheduled health services seems practical and associated with increased weight gain

Anaemia in schoolchildren in eight countries in Africa and Asia

Objective: To report on the haemoglobin concentrations and prevalence of anaemia in schoolchildren in eight countries in Africa and Asia. Design: Blood samples were collected during surveys of the health of schoolchildren as a part of programmes to develop school-based health services. Setting: Rural schools in Ghana, Indonesia, Kenya, Malawi, Mali, Mozambique, Tanzania and Vietnam. Subjects: Nearly 14 000 children enrolled in basic education in three age ranges (7-11 years, 12-14 years and >/= 15 years) which reflect the new UNICEF/WHO thresholds to define anaemia. Results: Anaemia was found to be a severe public health problem (defined as >40% anaemic) in five African countries for children aged 7-11 years and in four of the same countries for children aged 12-14 years. Anaemia was not a public health problem in the children studied in the two Asian countries. More boys than girls were anaemic, and children who enrolled late in school were more likely to be anaemic than children who enrolled closer to the correct age. The implications of the four new thresholds defining anaemia for school-age children are examined. Conclusions: Anaemia is a significant problem in schoolchildren in sub-Saharan Africa. School-based health services which provide treatments for simple conditions that cause blood loss, such as worms, followed by multiple micronutrient supplements including iron, have the potential to provide relief from a large burden of anaemia

Health and cultural factors associated with enrolment in basic education: a study in rural Ghana

This inter-disciplinary study compares the health status of school-age children in Ghana, both enrolled and non-enrolled, and examines these results within a wider socio-economic and socio-cultural context including kinship and livelihood. Children matched for age and sex who were not enrolled in Primary School were significantly shorter and more stunted than enrolled children were, and 70% of all Primary school-age children were anaemic. Young children from farming communities were significantly more undernourished than children from fishing communities. Adolescent non-enrolled boys were more heavily infected with Schistosoma haematobium, and were more likely to be anaemic than enrolled adolescent boys. The data indicate how health and health related factors may influence and affect enrolment and how socio-economic indicators, livelihood, and kinship may also constrain enrolment and, in turn, affect child health. This study sheds light on the complex factors that may influence enrolment in education and provides novel data on the similarities and differences between the health of enrolled and non-enrolled children in rural Ghana

Ill-health reported by schoolchildren during questionnaire surveys in Ghana, Mozambique and Tanzania.

BACKGROUND: Insufficient attention has been paid to the health problems of school-age children in sub-Saharan Africa. A questionnaire administered to schoolchildren about their ill-health has been developed to identify schools in which urinary schistosomiasis occurs. The data collected during the interviews can also be used to assess other common health problems. OBJECTIVES: To analyse data collected during health questionnaires in schools to assess how schoolchildren perceive their own health, and to compare the findings between three countries in sub-Saharan Africa. METHODS: Questionnaires asking about recent health problems were administered by teachers to schoolchildren in 120 primary schools in Mozambique, 52 primary schools in Tanzania and 298 primary schools in Ghana. A total of 67 002 children aged 8-15 years took part. RESULTS: Of the 10 health problems asked about in all questionnaires, the average number reported by each child was 3.9 in Ghana, 3.4 in Mozambique and 3.1 in Tanzania. The distributions of the prevalence of each condition among schools were similar and the prevalence of all conditions showed a similar ranking. For most conditions a greater percentage of girls than boys reported each health problem. CONCLUSIONS: Schoolchildren in Ghana, Mozambique and Tanzania do not perceive themselves to be healthy. The pattern of reported health problems was similar in each country. School health questionnaires are worthy of further study and validation

Modelling heterogeneity and the impact of chemotherapy and vaccination against human hookworm

There is a growing emphasis on the development of vaccines against helminths (worms), and mathematical models provide a useful tool to assess the impact of new vaccines under a range of scenarios. The present study describes a stochastic individual-based model to assess the relative impact of chemotherapy and vaccination against human hookworm infection and investigates the implications of potential correlations between risk of infection and vaccine efficacy. Vaccination is simulated as a reduction in susceptibility to infection and the model includes population heterogeneities and dynamical waning of protection. To help identify appropriate measures of vaccine impact, we present a novel framework to quantify the vaccine impact on the infection-associated morbidity and introduce a measure of symmetry to study the correspondence between reduction in intensity and reduction in morbidity. Our modelling shows that, in high-transmission settings, the greatest impact of vaccination will be attained when vaccine efficacy is the greatest among individuals harbouring the heaviest worm burdens, and that the decline of morbidity primarily depends on the level of protection attained in the most at risk 8–12% of the population. We also demonstrate that if risk of infection and vaccine protection are correlated, there is not always a direct correspondence between the reduction in worm burden and in morbidity, with the precise relationship varying according to transmission setting