Efficacy of Three Novel Bi-treated Long Lasting Insecticidal Nets
- Conditions
- AnaemiaMalaria
- Interventions
- Other: Standard LLINOther: pyriproxyfen LLINOther: Chlorfenapyr LLINOther: Piperonyl butoxide LLIN
- Registration Number
- NCT03554616
- Lead Sponsor
- London School of Hygiene and Tropical Medicine
- Brief Summary
The massive scale-up of Long Lasting Insecticidal Nets (LLIN) has led to a major reduction in malaria burden (up to 50%) in many sub-Saharan African countries. This progress is threatened by the wide scale selection of insecticide resistant malaria vectors. New types of LLIN combining a mixture of two insecticides or an insecticide and a synergist have been developed to control resistant mosquitoes.
The efficacy of three bi-treated LLIN are compared to a standard LLIN in a four-arm, single blinded, cluster-randomized trial in Misungwi district, Tanzania. The arms are; 1/ Royal Guard, a net combining pyriproxyfen (PPF), which is known to disrupt female reproduction and fertility of eggs, and the pyrethroid alpha-cypermethrin, 2/Interceptor G2, LLIN incorporating a mixture of two adulticides with different modes of action; chlorfenapyr and a pyrethroid (alpha-cypermethrin), and 3/ Olyset Plus an LLIN which incorporates a synergist, piperonyl butoxide (PBO), to enhance the potency of pyrethroid insecticides, and 4/ The control arm: Interceptor treated a standard LLIN treated with alpha-cypermethrin.
The primary outcome of the trial will be cross-sectional community prevalence of malaria infection (by RDT) in children aged 6 months to 14 years at 12 and 24 months post-intervention.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 4200
- At least one child between 6 months to 14 years old having permanent residence in selected household
- Having an adult caregiver willing to provide written consent for the household and clinical survey
- Dwelling not found or vacant during the survey
- No adult caregiver capable to give informed consent
- Children severely ill
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Standard LLIN Standard LLIN Interceptor® (BASF Corporation) is a single pyrethroid-treated LLIN with alpha-cypermethrin (coated onto filaments) at a target dose of 200 mg/m2 of polyester fabric. This LLIN will be distributed to all the households in 21 clusters on a 1 LLIN per two household residents basis. Pyriproxyfen LLIN pyriproxyfen LLIN Royal Guard® (Disease Control Technologies, LLC) is a Long Lasting Insecticidal Net made of polyethylene incorporating a mixture of 225 mg/m2 pyriproxyfen and 261mg/m2 alpha-cypermethrin. This LLIN will be distributed to all the households in 21 clusters on a 1 LLIN per two household residents basis. Chlorfenapyr LLIN Chlorfenapyr LLIN Interceptor® G2 (BASF corporation) is a LLIN made of polyester coated with a wash-resistant formulation of 200 mg/m2 chlorfenapyr and 100 mg/m2 alpha-cypermethrin. This LLIN will be distributed to all the households in 21 clusters on a 1 LLIN per two household residents basis. Piperonyl butoxide LLIN Piperonyl butoxide LLIN Olyset® Plus (Sumitomo Chemicals) is a LLIN combining Piperonyl butoxide (400mg/m2) and the repellent pyrethroid permethrin (800 mg/m2) incorporated into the polyethylene fibres. This LLIN will be distributed to all the households in 21 clusters on a 1 LLIN per two household residents basis.
- Primary Outcome Measures
Name Time Method Malaria infection prevalence in children 6 months to 14 years 24 months post intervention Malaria prevalence will be assessed using Malaria Rapid Diagnostic test (CareStart Malaria histidine-rich protein 2 (HRP2)/plasmodium lactate dehydrogenase (pLDH) Combo, DiaSys, UK)
- Secondary Outcome Measures
Name Time Method Insecticide content in Long Lasting Insecticidal Net (LLIN) at 0, 12, 24, 30, 36 months post intervention 30 LLINs will be collected at yearly interval and Insecticide content in g/kg assessed with High-performance liquid chromatography (HPLC)
Mortality in Anopheles after one hour exposure to every study LLIN at 0, 6, 12, 18, 24, 30, 36 months post intervention 30 LLINs will be sampled every 6 months and tested in cone bio assay or tunnel test using resistant Anopheles and susceptible Kisumu Anopheles to assess for bio efficacy. 24, 48 and 72 hours mortality post exposure will be recorded.
Malaria infection prevalence in children 6 months to 14 years 36 months post intervention Malaria prevalence will be assessed using Malaria Rapid Diagnostic test (CareStart Malaria histidine-rich protein 2 (HRP2)/plasmodium lactate dehydrogenase (pLDH) Combo, DiaSys, UK)
Cost & DALYs of each type of bi-treated LLIN Three years post intervention Cost of each intervention will be gathered and used to calculate cost per malaria case averted and cost per DALY averted
LLIN usage at 6, 12, 18, 24, 30, 36 months post intervention The proportion of study participant declaring sleeping under a LLIN the previous night will be assessed during household survey every 6 months using a questionnaire.
Incidence of malaria cases in children 6 months to 10 years Two years post intervention follow up Malaria incidence cases will be assessed using Malaria Rapid Diagnostic test (CareStart)
Prevalence of anaemia in children under 5 years old 12, 18, 24, 30, 36 months post intervention Hemoglobin (Hb) concentration will be tested to assess anaemia (\<8 g/dL) using HemoCue Hb 201+.
Indoor Anopheles density Three years post intervention follow up Anopheles density per house per night will be assess every quarter in 8 houses per cluster using light trap. Anopheles density and sporozoite rate will be used to estimate the entomological inoculation rate (EIR)
Sporozoite rate Three years post intervention follow up A sub-samples of Anopheles collected indoor will be tested for Plasmodium falciparum circumsporozoite protein using an ELISA test. Sporozoite rate will be used to estimate the EIR with Anopheles density.
Trial Locations
- Locations (1)
District Misungwi
🇹🇿Misungwi, Mwanza, Tanzania