Insecticidal paints as a new malaria control tool in Tanzania

Tanzania faces a significant challenge regarding malaria, with 93% of its population at risk and over 6 million recorded cases annually. Small children and pregnant women in rural areas bear the highest burden, 70% of the malaria deaths in Sub-Saharan Africa concerning children under 5 years old. (WHO 2016 ; WHO 2021).

Since most malaria transmissions occur indoors in Sub-Saharan Africa (Huho 2013), malaria control interventions focus in indoor solutions, such as indoor residual spraying and insecticidal bed nets. While effective, indoor residual spraying is expensive, obstructed by user acceptance issues as well as environmental concerns, and requires well-trained spray teams to apply it. Bed nets on the other hand only protect beneficiaries while they are sleeping. Additionally, mosquitos have developed resistance to the majority of the recommended public health insecticides. (WHO 2020).

Paints that repel and kill mosquitos, called insecticidal paints, could supplement existing interventions. The Kilimanjaro Christian Medical University College (KCMUCo) is proposing to compare insecticidal paints that contain different kinds of insecticides to see which ones are the most effective. This work remains necessary before undertaking community studies, the next step for the development of the insecticidal paints as a viable malaria control tool.

The study will take place in two settings in North-East Tanzania, and it will be done in collaboration with the London School of Hygiene & Tropical Medicine and the National Institute for Medical Research in Tanzania. The project team is using for their experiment Insefly Corporations’s water-based insecticidal paints, designed for applying on indoor walls where mosquitoes usually settle. These paints use various insecticides, reducing the chance of insects becoming resistant to a single type. Their unique formulation ensures longer-lasting insecticidal effects compared to indoor residual spraying, offering protection against mosquito bites throughout the entire transmission season (Schiøler and al, 2016, Mosqueira B et al 2015).

The objectives of the study are identifying the most suitable insecticidal paint formulations and gaining a certification from the World Health Organization (WHO). The WHO certification could enable Insecticidal paints’ application more broadly in malaria-endemic countries to reduce disease burden, save lives and enhance economic growth and welfare.

The study will roll out in two distinct phases:

• Phase I includes laboratory tests which will measure how long the different paint formulations continue to effectively repel or kill the targeted insects after application.
• Phase II takes place in experimental huts, where the two best paints selected in Phase I are tested. The trial answers the questions on what kind of safety and environmental aspects need to be taken into account for using the paints.