Clinical trial NCT02392832: Evaluation of Long-Lasting Microbial Larvicides in Reducing Malaria Transmission and Clinical Malaria Incidence
Official title: Impact and Cost-Effectiveness of Long-Lasting Microbial Larvicides in Reducing Malaria Transmission and Clinical Malaria Incidence: a Cluster-Randomized Controlled Trial in Western Kenya
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Malaria
Keywords: long-lasting microbial larvicide
intervention
cluster randomised controlled trial
Anopheles mosquito
Lead sponsor: University of California, Irvine
Sponsor class: OTHER
Collaborators: name: Kenya Medical Research Institute
First posted: 2015-03-19
Enrollment: 240000
Sex: ALL
Minimum age (years): 7
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: OTHER

Brief summary: In the past decade, massive scale-up of insecticide-treated nets (ITN) and indoor residual spraying (IRS), together with the introduction of artemisinin-combination treatments, have led to substantial reductions in malaria prevalence and incidence in African highlands. However, rising insecticide resistance and increased outdoor transmission have greatly hampered the effectiveness of ITN and IRS because the current indoor-based interventions do not target the outdoor-biting mosquitoes. Therefore, new supplemental interventions that can tackle outdoor transmission and pyrethroid insecticide resistance are urgently needed. The central objective of this study is to determine the efficacy and cost-effectiveness of EPA-approved long-lasting microbial larvicides in reducing malaria transmission and clinical malaria incidence in western Kenya highlands.

Detailed description: In the past decade, massive scale-up of insecticide-treated nets (ITNs) and indoor residual spraying (IRS), together with the use of artemisinin combination treatments, have led to major changes in malaria epidemiology and vector biology. Along with the significant reduction in overall malaria prevalence and incidence, extensive use of insecticides has created large selection pressures for resistance in the malaria vector populations and for potential outdoor transmission, which appears to be limiting the success of ITNs and IRS. Because IRS and ITN have little impact on outdoor resting and early biting vectors, outdoor transmission represents one of the most important challenges in malaria control. Therefore, new interventions that can augment the current public health measures to reduce outdoor transmission are urgently needed. Larval control has historically been very successful and is widely used for mosquito control in many parts of the world, except in Africa. Factors limiting the use of larvicides include high costs associated with frequent habitat re-treatment. Now a new US EPA-approved long-lasting formulation, potentially effective for 6 months is available. The central objective of this study is to determine the effect of long-lasting microbial larviciding on the incidence of clinical malaria and reduction of transmission intensity. Our hypothesis is that addition of long-lasting microbial larviciding to ongoing ITN and IRS programs will lead to significant reductions in both indoor and outdoor malaria transmission and malaria incidence.

Eligibility criteria: Inclusion Criteria:

* All clinical malaria cases from participated local hospitals and clinics.

Exclusion Criteria:

* Infants younger than 6 months.

Primary outcomes:
measure: Changes in clinical malaria incidence rate
timeFrame: baseline and 4 months following the interventions
Secondary outcomes:
measure: Changes in vector abundance
timeFrame: baseline and 4 months following the interventions
measure: EIR
timeFrame: baseline and 4 months following the interventions
Other outcomes:
Locations:
city: Kisumu
country: Kenya
facility: Kenya Medical Research Institute
Study officials:
affiliation: University of California at Irvine
name: Guiyun Yan, Ph.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Zhou G, Wiseman V, Atieli HE, Lee MC, Githeko AK, Yan G. The impact of long-lasting microbial larvicides in reducing malaria transmission and clinical malaria incidence: study protocol for a cluster randomized controlled trial. Trials. 2016 Aug 25;17(1):423. doi: 10.1186/s13063-016-1545-4.