Impact of Indoor Residual Spraying and Insecticide-treated Bed Nets on Malaria Transmission in Sub-Saharan Africa Using Mathematical Modelling

• Main Author: Tomayer, Andrew
• Other Authors: Smith, Robert
• Language: en
• Published: Université d'Ottawa / University of Ottawa 2016
• Subjects: Malaria; Mathematical modelling; Long-lasting insecticidal nets; Indoor residual spraying; Vector control
• Online Access: http://hdl.handle.net/10393/35376; http://dx.doi.org/10.20381/ruor-334

Background: Malaria causes over 400,000 estimated deaths annually worldwide, with about 90% in sub-Saharan Africa. Long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) are two vector-control interventions proven to reduce malaria transmission, but their use together compared to separate has shown mixed results. Methodology: We used a mathematical model to examine the impact of LLINs and IRS on malaria transmission. Time-series analyses and basic reproductive numbers (R0) were developed using MATLAB. We also assessed IRS timing and performed a sensitivity analysis on R0. Results: Modelling scenarios combining LLINs with IRS were similar to those with LLINs alone. Shorter IRS impulses had greater reductions in mosquito populations. The LLIN feeding-inhibition rate was a key parameter with a negative correlation to R0. Discussion/Conclusion: We developed an understanding of the effect of vector-control strategies on malaria transmission. IRS, when paired with LLINs, showed only small improvements in reducing malaria transmission compared to LLINs alone. These results can assist vector-control programmes.