Adaptive Interventions for Optimizing Malaria Control: a Cluster-Randomized SMART Trial

Summary

In the past decade, massive scale-up of long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) have led to significant reductions in malaria mortality and morbidity. Nonetheless, malaria burden remains high, and a dozen countries in Africa show a trend of increasing malaria incidence over the past several years. The high malaria burden in many areas of Africa underscores the need to improve the effectiveness of intervention tools by optimizing first-line intervention tools and integrating newly approved products into control programs. Vector control is an important component of the national malaria control strategy in Africa. Because transmission settings and vector ecology vary among countries or among districts within a country, interventions that work in one setting may not work well in all settings. Malaria interventions should be adapted and re-adapted over time in response to evolving malaria risks and changing vector ecology and behavior. The central objective of this application is to design optimal adaptive combinations of vector control interventions to maximize reductions in malaria burden based on local malaria transmission risks, changing vector ecology, and available mix of interventions approved by the Ministry of Health in each target country. The central hypothesis is that an adaptive approach based on local malaria risk and changing vector ecology will lead to significant reductions in malaria incidence and transmission risk. The aim of this study is to use a cluster-randomized sequential, multiple assignment randomized trial (SMART) design to compare various vector control methods implemented by the Ministry of Health of Kenya in reducing malaria incidence and infection, and develop an optimal intervention strategy tailored toward to local epidemiological and vector conditions.

Conditions

• LLIN, PBO LLIN, IRS, Larviciding

Interventions

OTHER

Regular long-lasting insecticidal nets

Olyset nets: containing 2% permethrin or PermaNet 2.0 containing 1.8 and 1.4 g/kg, respectively, for 75 and 100 denier yarn

OTHER

LLIN plus Piperonyl butoxide-treated LLIN

Olyset Plus: containing 2% permethrin and 1% PBO

OTHER

Long-lasting microbial larvicide

Semi-permanent and permanent habitats will be treated with FourStar® 180-day Briquets using the recommended dosage of 100 ft2 water surface per briquet

OTHER

Indoor residual spraying with micro-encapsulated pirimiphos-methyl or other insecticides

Each dwelling's interior walls and ceilings will be sprayed with micro-encapsulated pirimiphos-methyl at the recommended dosage of 1g/m² and at the recommended frequency of once a year or twice a year. Other insecticides may be used to replace the Actellic 300 CS depends on Kenya government policy, current policy requires rotating different insecticides annually.

Sponsors & Collaborators

• University of California, Irvine

  lead OTHER

Principal Investigators

• Guiyun Yan, Ph.D. · University of California at Irvine

• John Githure, Ph.D. · Tom-Mboya University, Kenya

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

TRIPLE

Model

SEQUENTIAL

Eligibility

Min Age

6 Months

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2019-12-01

Primary Completion

2024-08-31

Completion

2024-08-31

Countries

• United States
• Kenya

Study Locations