Long-acting Spatial Emanators / Repellents (LASER)

Official title

Long-acting Spatial Emanators / Repellents (LASER) vs Indoor Residual Spraying (IRS) in Western Kenya: a Cluster-randomised Trial

Overview

Malaria is a major problem in western Kenya, particularly around Lake Victoria. Whilst current prevention methods like bed nets and vaccines help to reduce malaria burden, additional tools are needed to better protect communities from malaria. The investigators will test a new technology called LASER Guardian™, which are devices that release chemicals to keep mosquitoes away from homes. The investigators will conduct a large study involving 69 villages in western Kenya over two years. Each village will be randomly chosen to receive one of three approaches: the new LASER devices, indoor residual spraying with insecticide (a method already known to work), or the standard prevention methods currently used. All villages will continue to receive the usual malaria prevention tools provided by the Kenyan government, including bed nets and vaccines. In villages receiving LASER, the investigators will install 2-3 small device inside structures once a year for two years. In villages receiving IRS, the investigators will spray the inside walls of homes with insecticide once a year for two years. The investigators want to find out if the LASER devices can reduce malaria better than current methods alone, and whether they work as well as indoor spraying. To do this, the investigators will carry out surveys of the community every six months over two years (four rounds in total), testing about 4,485 children between ages 1 and 15 from approximately 3,450 households in each survey to see how many have malaria. The investigators will also work with local health clinics to track malaria cases, study mosquitoes to understand how the interventions affect them, talk with community members about their experiences, and calculate the costs of these different approaches. This study will help us understand whether LASER tool can effectively protecting against malaria in Kenya and other African countries where malaria is common.

Interventions

• Device Guardian
  The SC Johnson long-acting product (Guardian™) is a vapor releasing product (VP) formed from a polyester (PET) mesh substrate carrier dosed with 2,500 mg of transfluthrin per unit (CAS No. 118721-89-3). Transfluthrin is a type I synthetic pyrethroid that acts through modulation of nerve axon sodium channels, causing neurotoxicity in insects. The product is intended to be used as spatial emanator for the control of mosquitoes. The insecticide emanates from the product and subsequently kills or di
• Device IRS with Pirimiphos - methyl
  In clusters that are randomised to the IRS arm, IRS will be carried out using pirimiphos-methyl (Actellic®300CS) manufactured by Syngenta, an organophosphate insecticide that is registered for use in Kenya and has demonstrated effectiveness in malaria vector control. The product will be obtained directly from Syngenta to ensure quality and authenticity, with proper documentation and chain of custody maintained throughout the procurement and storage process.

Primary outcome measures

• Malaria prevalence [Time frame: Measured one time in randomly selected participants at baseline and 6, 12, 18 and 24 months post intervention deployment.]

Secondary outcome measures (12)

• Prevalence of parasitaemia in children aged 1-5 years [Time frame: Measured one time in randomly selected participants at baseline and 6, 12, 18 and 24 months post intervention deployment.]
• Prevalence of parasitaemia in children aged 6-10 years [Time frame: Measured one time in randomly selected participants at baseline and 6, 12, 18 and 24 months post intervention deployment.]
• Prevalence of parasitaemia in children aged 11-15 years [Time frame: Measured one time in randomly selected participants at baseline and 6, 12, 18 and 24 months post intervention deployment.]
• Prevalence of anaemia in children under 5 years [Time frame: Measured at baseline and 6, 12, 18 and 24 months post intervention deployment]
• Proportion of households that owned at least one LLIN [Time frame: Measured at baseline and 6, 12, 18 and 24 months post intervention deployment]
• Proportion of households with at least one LLIN for every two occupants [Time frame: Measured at baseline and 6, 12, 18 and 24 months post intervention deployment]
• Proportion of household residents who slept under an LLIN the previous night [Time frame: Measured at baseline and 6, 12, 18 and 24 months post intervention deployment]
• LASER intervention coverage [Time frame: Measured at 6, 12, 18 and 24 months post initial intervention deployment]
• Indoor residual spraying (IRS) coverage [Time frame: Measured at 6, 12, 18 and 24 months post inital intervention deployment]
• Malaria incidence in patients of all ages from health facility surveillance [Time frame: Data captured monthly for 24 months post intervention deployment]
• Anopheles spp. vector density [Time frame: Measured at baseline and 6, 12, 18 and 24 months post initial intervention deployment]
• Anopheles mosquitoes species composition [Time frame: Measured at baseline and 6, 12, 18 and 24 months post intervention deployment]

Eligibility criteria

The inclusion criteria are:

• Child aged 1-15 years
• Usual resident (a person who has been residing in the survey area for at least the past 4 months) who was present in the sampled household on the night before the survey
• Agreement of adult or parent/guardian (of children) to provide informed consent
• Agreement of child aged 12 years or older to provide assent

The exclusion criterion is:

1\. Child not at home after 3 attempts

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Open label

Primary purpose

Prevention

Study locations

Kenya · 1 center

• KEMRI Center for Global Health Research — Kisumu

Identifiers

NCT: NCT07387341 · 101190818

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗