Indoor Residual Spraying (IRS) is one of the primary vector control interventions for reducing and interrupting malaria transmission which requires the application of insecticide to the interior walls of a dwelling to kill mosquitoes.
This requires specialist equipment with manually operated compression sprayers and, although effective, there is potential for significant improvements. IVCC has been working with industry partners, researchers and IRS teams to improve current application technology and explore innovative application methods with the potential to significantly improve efficiency, ease of use, quality control, safety and implementation costs.
IK Smart Light
Working closely with IVCC and IRS implementation partners, the Goizper Group has developed a tool, the IK Smart Light, to assist IRS implementers in training spray operators and to assist spray operators in delivering the correct dose of insecticide while spraying walls. The IRS application guidelines call for spray operators to maintain a spray distance of 45cm from the wall, to create a swath of 75cm and to take 5 seconds to treat a 2m tall wall.
However, there is no simple way to teach this technique or to check if spray operators are meeting this standard. The objectives of the development of the IK Smart Light are to simplify training, and improve IRS delivery through higher quality training and improved consistency of application to reduce areas of over and under dosing which can negatively impact IRS campaigns through higher costs and lower and shorter efficacy. The IK Smart Light continuously guides spray operators as they apply spray and will provide supervisors with data to assess constancy of delivery through a smartphone app.
A small number of early prototypes were tested by partners in 2019. Following the 2019 field tests, an upgraded version of the device was designed and two large scale field evaluations will take place in 2021. The features of the new model include modifications to keep the sensor clean, a flow detector to measure the actual amount of insecticide that is sprayed, inclusion of an LED light to shine on the surface to assist SOPs during spraying, improved robustness and the addition of a rechargeable battery. The 2021 field test of the IK Smart Light will focus on evaluating potential improvements in operational efficiency, spray quality, and spray reporting.
Electrostatic discharge (ED) sprayer for improved IRS applications
Electrostatic Discharge (ED) Sprayer for Improved IRS Applications is a Proof of Concept (PoC) project, aimed at developing and establishing feasibility of an oil-based electrostatic sprayer for IRS sprays.
To be successful, the new sprayer must at least match, and ideally exceed, the biological control of existing IRS technology (e.g. water-based pump sprayers) with an oil-based or ready to use formulation.
The uniformity of the spray on different surfaces from the new sprayer will also be measured. The main potential benefit may be in extending the residual effect of actives to reduce frequency of application and extend period of protection.
Operator exposure may be reduced since the electrostatic-ally charged spray droplets are attracted to the target surface and away from the operator. This could lower operator risk of inhalation and exposure.
Track sprayer
IRS is a widely applied vector control intervention, however ascertaining how consistent the delivery of insecticide to a wall surface has been is, has historically been a major issue.
This is important when performing experimental trials (such as hut trials), which are reliant on an even application of insecticide. In simulated IRS conditions, the consistency and uniformity of sprays created by an automated track spray system are compared to a well-trained human spray operator using a standard compression sprayer. Improved IRS sprays from track spraying will result in a new procedure for testing IRS sprays in experimental hut trials.
The project was started 2016 with testing being done in a laboratory setting in 2017 and field trials in test huts in Tanzania in 2018. Funding for this Project was provided by USAID.
