Long-acting Spatial Emanators / Repellents (LASER)

NCT07387341 | Not Yet Recruiting DMC

• 1 other identifier: 101190818
• Study Type: interventional
• Target: 22,815
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Malaria Transmission; Malaria Prevention; Malaria

Keywords

spatial repellents; spatial emanators; Indoor Residual Spraying; Kenya

Outcome Measures

Primary Outcomes (1)

• Malaria prevalence

  The primary outcome of the study will be malaria parasite prevalence (any plasmodium species) in participants aged 1-15 years old

  Measured one time in randomly selected participants at baseline and 6, 12, 18 and 24 months post intervention deployment.

Secondary Outcomes (26)

• Prevalence of parasitaemia in children aged 1-5 years

  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

  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

  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

  Measured at baseline and 6, 12, 18 and 24 months post intervention deployment

• Proportion of households that owned at least one LLIN

  Measured at baseline and 6, 12, 18 and 24 months post intervention deployment

Study Arms (3)

LASER

EXPERIMENTAL

Device: Guardian

IRS

EXPERIMENTAL

Device: IRS with Pirimiphos - methyl

Standard control

NO INTERVENTION

Interventions

Guardian DEVICE

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 disrupts the biting behaviour of the surrounding vector population. The LASER product will be procured locally from the SC Johnson factory in Nairobi, Kenya (SC Johnson).

LASER

IRS with Pirimiphos - methyl DEVICE

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.

IRS

Eligibility Criteria

• Age: 1 Year - 15 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17)

You may qualify if:

• 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
• \. Child not at home after 3 attempts

Sponsors & Collaborators

• Liverpool School of Tropical Medicine: lead
• Kenya Medical Research Institute: collaborator
• Institute of Tropical Medicine, Belgium: collaborator
• Radboud University Medical Center: collaborator
• Centers for Disease Control and Prevention: collaborator

Study Sites (1)

KEMRI Center for Global Health Research

Kisumu, Kenya

Location

MeSH Terms

Conditions

Malaria

Condition Hierarchy (Ancestors)

Protozoan Infections; Parasitic Diseases; Infections; Mosquito-Borne Diseases; Vector Borne Diseases

Central Study Contacts

Sarah Staedke

CONTACT

+254796667290; sarah.staedke@lstmed.ac.uk

Natalie Tate

CONTACT

natalie.tate@lstmed.ac.uk

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Two interventions will be evaluated in this trial: (i) LASER (intervention #1) and (ii) IRS with pirimiphos-methyl (intervention #2), as compared to standard of care (control) in a parallel 1:1:1 open label cluster randomised trial . All clusters will receive standard malaria control interventions, including LLINs distributed by the Kenyan NMCP and malaria vaccines (when and where these are deployed).

Study Record Dates

• First Submitted: December 19, 2025
• First Posted: February 4, 2026
• Study Start: January 17, 2026
• Primary Completion (Estimated): April 30, 2028
• Study Completion (Estimated): April 30, 2028
• Last Updated: February 4, 2026

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will share

Locations

KE (1)