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A mathematical model, based on a deterministic differential equation framework, has been developed to predict the impact of community chemotherapy programmes for human schistosomiasis. Here, this model is validated using data collected from a long-term control programme for urinary schistosomiasis on the island of Pemba, Zanzibar, United Republic of Tanzania, initiated in 1986 and still ongoing, in which schoolchildren were offered praziquantel chemotherapy every 6 months. Prevalence of infection and blood in urine were monitored in all the schools (total 26000 children from 60 schools) and more detailed data were collected in selected evaluation schools. Model predictions were run by using the initial prevalence as input. The predictions were very close to the observed decreases in prevalence and in prevalence of blood in urine. The correspondence improved further when the data were combined, going from single school level to district, and when the entire data set was combined. The accuracy of the predictions suggests that this model could be used as a tool to predict the consequences of chemotherapy control programmes. It is currently in press as a Windows software package under the name of ‘EpiSchisto’.

School-based deworming programmes have been promoted as a cost-effective strategy for control of nematode infection in developing countries. While numerous efficacy studies have been conducted, there is little information on actual programme effectiveness in areas of intense transmission.

A long-term schistosomiasis control programme was initiated on Pemba Island,Tanzania in 1986 with the aim of eliminating morbidity due to Schistosoma haematobiuminfection. The programme used haematuria as a community indicator of morbidity for surveillance and for identifying individuals for selective population chemotherapy. Analysis of the first 3 evaluation studies showed that the prevalence of microhaematuria was linearly related to the prevalence of infection, and that visually detectable haematuria was a marker of the intensity of infection and risk of morbidity in a community. These relationships remained consistent during repeated community-based chemotherapy, suggesting that measures of haematuria may be useful tools for surveillance.

The hookworms, Ancylostoma duodenale and Necator americanus, cause significant gastrointestinal blood loss. In clinical studies, greater blood losses have been reported with A. duodenale. However, there has been no evidence that endemic A. duodenale infection has greater impact than N. americanus infection on the iron status of populations.

The purpose of this brief introduction to the supplement that follows is to highlight the current unique opportunity to coordinate intestinal helminth control programmes with the relatively new global initiative to eliminate lymphatic filariasis. Such synergy at global, regional, national and local levels has the potential to greatly enhance the impact, decrease the cost and facilitate sustainability in both of these health programmes.

The purpose of this brief introduction to the supplement that follows is to highlight the current unique opportunity to coordinate intestinal helminth control programmes with the relatively new global initiative to eliminate lymphatic filariasis. Such synergy at global, regional, national and local levels has the potential to greatly enhance the impact, decrease the cost and facilitate sustainability in both of these health programmes.