Optimizing Evidence for Vector Control Interventions Work Stream Meeting

Impact of insecticide resistance in Anopheles arabiensis on effectiveness of malaria vector control in Sudan – Hmooda Kafy, National Malaria Control Programme, Sudan The objective of the trial was to assess the impact of insecticide resistance on the effectiveness of malaria vector control in Sudan and to determine the effects of different combinations of vector control intervention combinations. The specific objectives were (1) to determine the impact of longlasting insecticide-treated nets (LLINs) and LLINs plus indoor residual spraying (IRS) on malaria control and (2) to determine the insecticide resistance status and underlying genetic mechanisms in the primary malaria vector An. arabiensis in four districts of Sudan. In each arm clusters were randomised to receive either LLINs alone or LLINs with IRS. The study was designed so that the 70 clusters in each of the two study arms were balanced in terms of insecticide resistance levels and between the four study areas. Clinical data were collected through active case detection in cohorts of 200 children in each study cluster using community health workers and cross-sectional surveys. Overall, LLIN use averaged approximately 80% from 2011 to 2013. In 2012 there was no evidence of a difference in parasite prevalence (Odds Ratio 1.45, 95% confidence interval (CI) 0.61 to 3.45) or incidence (Rate Ratio 1.11, 95% CI 0.68 to 1.80) in clusters with LLINs alone compared to clusters with LLINs and IRS. The study has two more years to run. 2013 findings have not been analysed yet.