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Head of Unit: Professor Daniel Chanramohan
Unit Research Degree Co-ordinator: Jonathan Cox
Unit Administrator: Mary Marimootoo

This multidisciplinary unit focuses on the control of diseases that are insect-borne, water-borne or associated with poor hygiene, mostly in developing countries. The DFID funded TARGETS consortium staff based in the unit work on communicable diseases and on overcoming the barriers to effective control of these diseases, an essential step towards achieving the Millennium Development Goals. Our work covers an extensive area of research on malaria control including vector control, insecticide-treated nets (ITN), intermittent preventive treatment (IPT), drug treatment regimes, epidemic early warning systems and socio-anthropological issues in malaria control.

Collaboration between chemical industry and Gates Malaria Partnership on vector control research has contributed to the development of a new BMGF programme the 'Innovative Vector Control Consortium" (IVCC) which is a collaboration between British, American and African research institutes to develop new tools for controlling malaria and dengue, and new technologies for supporting vector control programmes. Sites and staff of the GMP programme will merge into IVCC and we shall responsibility for coordinating the field evaluation of new control tools in Africa and elsewhere.

We have been evaluating a number of alternative insecticides to supplement the pyrethroids, new candidate long lasting nets, and long lasting cost-effective spray formulations that have the potential to replace DDT. We also continue to work on ITN delivery systems and monitoring and evaluation of large scale programmes. A study in Tanzania showed that coverage of ITN by social marketing was higher in villages with high density of culex mosquitoes (93%) than in villages with intense malaria transmission (16%) with nearly half of the nets torn and untreated. By contrast, in villages where ITN had been provided free to whole communities, about 90% of the nets continued to be brought for annual re-treatment for 3-5 years

In collaboration with the Institute of Tropical Medicine in Antwerp and the National Malaria Control Program of Rwanda the unit staff showed that amodiaquine (AQ) + sulphadoxine-pyremithamine (SP) is not well tolerated by adults and that this combination has low adherence to treatment. They also showed that resistance to AQ+SP has spread rapidly in Rwanda and that fixed artemisinin-based combinations Artekin and Coartem are efficacious and safe to replace AQ+SP. Another study in Ghana showed that AQ or AQ+SP is still efficacious for clearing malaria parasitaemia in pregnant women. The unit staff are involved in several studies of efficacy and safety of various antimalarial drugs for intermittent preventive treatment in pregnant women, infants and children in Ghana, Tanzania, Uganda, The Gambia and Senegal. The impact IPT delivered through the schools on the health and education of schoolchildren has been recently investigated by a study in western Kenya. In collaboration with GSK, unit staff are working on pharmacovigilance and post marketing surveillance of antimalrials in Africa.

We are running a number of studies in Tanzania as part of the Joint Malaria Programme to find improved ways to implement initiatives to reduce child mortality in Africa. An assessment of the quality of care in public hospitals in NE Tanzania indicated severe deficiencies in the basic provision of care and we are addressing a number of these issues in collaboration with MoH in Tanzania. A related study seeks to identify the cause of severe illness in hospitalised children and aims to contribute to guidelines for care of severely ill children in Africa. A study of the effectiveness and costs of 'rapid tests' in directing treatment for non-severe malaria in Tanzania showed that rapid tests are moderately more expensive than blood slides but the costs are at least partly offset by higher accuracy of results. However, the most striking finding was the degree to which patients continue to be treated for malaria in spite of a negative malaria test, be it rapid test or blood slide. This highlights the urgent need to improve current prescribing practices if ACT is to make a sustainable contribution to reducing malaria burden in Africa.

Unit staff have been working with the WHO Child Health Epidemiology Reference Group (CHERG) on new estimates of the burden of malaria morbidity and mortality in sub-Saharan Africa for the year 2000, as well as working WHO/RBM to estimate the burden of malaria anaemia in sub-Saharan Africa in children under five.We continue to support a major East African initiative to develop malaria epidemic early warning systems. Operational systems have been implemented in key epidemic-prone highland districts of Kenya and Uganda and have already been shown to be effective at detecting the early onset of outbreaks, including a significant epidemic event in south west Uganda in 2006. Efforts are now focusing on scaling up piloted systems to the national level. Staff are also involved in evaluating the operational effectiveness of schistosomiasis control as implemented by the Schistosomiasis Control Initiative in several African countries.

A Cochrane review was recently completed of the effect of household water treatment on diarrhoeal disease which showed that interventions to improve drinking water quality do reduce the occurrence of diarrhoea in adults and children, and that household-based interventions are more effective than conventional improvements in water supplies. The Hygiene Centre continues to collaborate fruitfully with Unilever. By making hand washing central to soap marketing in Africa and Asia, the company is creating large scale, and above all sustainable, solutions to a pressing health problem. The collaboration has also allowed us to learn the techniques of behaviour change from their top marketers. Unilever recently brought a team of 8 marketers to Vietnam to share their approach to behaviour change with health professionals in Government, NGOs and agencies, laying the foundations for Vietnam's national hand washing initiative; the class will be replicated in other countries. In a study of the sustainability of hygiene behaviour change after the ending of a hygiene promotion programme, we have found a slow decline in the prevalence of hand washing among mothers in Kerala, India, with a half-life of about ten years, comparable with the rate of generational succession. The finding that such behaviour change is sustained for many years, confirmed by parallel studies in five other countries, has important implications for the cost-effectiveness of behaviour change interventions.

Leishmaniasis research in the Unit currently has four main focuses: (1) developing risk maps for zoonotic visceral leishmaniasis (ZVL), and identifying the environmental factors responsible for the observed distributions (throughout the Mediterranean region and in Iran); (2) measuring the impact of insecticide impregnated dog collars on ZVL incidence and investigating factors that determine the extent of this impact (in Iran); (3) measuring the effectiveness of long-lasting insecticide treated bednets on the incidence of anthroponotic visceral leishmaniasis (in India and Nepal); and (4) measuring the extent and distribution of antimonial drug resistance amongst Leishmania tropica strains, responsible for anthroponotic cutaneous leishmaniasis in Syria.

In Chagas disease, the unit continues to work closely with Colombian and Venezuelan institutions to help improve the targeting of the national surveillance and vector control programmes. In collaboration with PEHRU and HPU, mathematical models have been developed to allow health policy makers to compare the cost-effectiveness of alternative surveillance and control strategies. These studies have now expanded into Guatemala where large scale control programmes have identified certain regions where house spraying is poorly effective. The current focus of research is identifying factors that determine this geographic variation in the effectiveness of vector control.The Unit is also involved in trials to investigate the chemical ecology of house dust mites and bed bugs in collaboration with Rothamsted Research Station.

The unit is involved in several vaccine trials. A clinical trial in Ghana showed that a new GSK DTPw-HBV/Hib-MenAC vaccine is immunogenic and safe when given to infants according the current EPI vaccination schedule and it provides protection against 7 important childhood diseases including meningococcus A and C. We are also involved in trials of the GSK's RTS,S/AS02D and RTS,S/AS01E vaccines against malaria in Tanzania and Ghana, and in trials of a human hookworm vaccine in Brazil. Modelling and cost-effectiveness studies of the hookworm vaccine are also underway.

The unit hosted a conference on 'methodological issues in field survey' in February 2006. The conference led to a special issue of Emerging Themes in Epidemiology which will be published early next year before the next conference which is scheduled in February 2007.

Unit staff continue to carry out advisory work for international, national and non-governmental organizations, on a wide range of health-related issues particularly in environmental health, water, sanitation and disease control.