S.A.N.T.E. (Spraying And Nets Towards malaria Elimination)

5 July 2011
Today, many partners are concerned with reducing malaria (WHO, National Control Programmes, The Global Fund, etc ) and the current best practice for malaria control is the use of Artemisinin-based combination therapies , e.g. Coartem®, and long-lasting impregnated nets (LLINs) for vector control tool. Many countries are also using indoor residual spraying (IRS) as it is a passive and a highly equitable intervention and DDT is very suitable for rural areas. In 2009, 29 countries in Africa were using IRS at the same time as LLIN and 13 were using IRSwith DDT, including The Gambia. Yet there is very little information about the effectiveness of DDT-IRS in Africa, particularly in areas with high bednet coverage, and it is essential to determine if IRS with DDT will provide additional protection against malaria over current best practice. This is the primary aim of the S.A.N.T.E. (Spraying And Nets Towards malaria Elimination) study which was developed in partnership with the Gambian National Malaria Control Programme (NMCP). DDT is considered highly suitable for IRS but we need to test alternative insecticides, not only because of environmental considerations but also to manage insecticide resistance. Thus, in addition to the monitoring insecticide resistance in the vectors, we will compare the anti-mosquito properties and persistence of two alternative insecticides to DDT in a small pilot study.

The study is in the middle of the second year of field work. In the Upper River Region in 2010 we enrolled 96 villages into 70 clusters, and working with the NMCP, half of these received either LLIN and LLIN plus IRS with DDT. The study is large enough to make it probable that differences between the two groups will be greater than that due to chance alone. The primary measure is the effect of these interventions on malaria cases in children resident in study villages and a cohort of almost 8000 children aged 6 months to 14 years has been enrolled. The SANTE field team is working with the Regional Health Team, community health nurses and village health workers to detect malaria attacks during the malaria transmission seasons in 2010 and 2011. The major secondary measure is the number malaria mosquitoes, and their infection with malaria parasites, inside study houses to estimate the effect of IRS on the exposure of the population to malaria infection. Also the additional cost of malaria cases averted by IRS with DDT against a background of complete coverage with LLIN will be determined based on material and labour costs. The final field survey will take place in late 2011 and results are expected in mid 2012.