Gambia Study Showed No Significant Reduction in Malaria Vectors from Indoor Residual Spraying

In my ongoing series on the efficacy of DDT as a public health measure, check out a recent study published in The Lancet. I’ve excerpted portions of the abstract:

Although many malaria control programmes in sub-Saharan Africa use indoor residual spraying with long-lasting insecticidal nets (LLINs), the two studies assessing the benefit of the combination of these two interventions gave conflicting results. We aimed to assess whether the addition of indoor residual spraying to LLINs provided a significantly different level of protection against clinical malaria in children or against house entry by vector mosquitoes.

We identified no significant difference in clinical malaria or vector density between study groups. In this area with high LLIN coverage, moderate seasonal transmission, and susceptible vectors, indoor residual spraying did not provide additional benefit.

When you read the study, you observe the care with which effective public environmental health research must be planned and the narrow conclusions which can then be drawn. People who believe that DDT could eliminate malaria are not following scientific research.