Impact of Insecticide Resistance on Vector Control
- Conditions
- Malaria, Falciparum
- Interventions
- Device: Long Lasting Insecticidal Nets (LLIN)Other: Indoor residual insecticide spraying (IRS)
- Registration Number
- NCT01713517
- Lead Sponsor
- London School of Hygiene and Tropical Medicine
- Brief Summary
The purpose of the study is to determine whether long lasting insecticidal nets and indoor residual insecticide spraying, alone or in combination, are effective for controlling insecticide resistant anopheles mosquitoes for malaria prevention.
- Detailed Description
The study will assess the impact that insecticide resistance has on the effectiveness of malaria vector control tools LLIN and IRS. This is done by a cluster randomised trials of universal coverage LLINs versus universal coverage LLINs in combination with IRS, with levels of baseline insecticide resistance in the main vector balanced between the two study arms. In each cluster resistance to the insecticide used on LLINs is monitored, and malaria incidence is estimated from cluster specific cohorts of children followed up over the duration of the study. Resistance impact will be assessed from the ratio of incidence rates in clusters with high compared to those with low resistance and from a continuous measure of resistance expressed as percentage loss of mosquito mortality when exposed to insecticide in standardised WHO tests. Resistance mechanisms will be studied in subsets of study clusters.
Recruitment & Eligibility
- Status
- UNKNOWN
- Sex
- All
- Target Recruitment
- 28000
- Children older than 6 months and younger than 10 years in approximately 100 randomly selected households in all 140 study clusters selected in the four study areas
- Children living in households within 1 km from the edge of a neighbouring cluster (the buffer zone)
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Universal coverage of Long Lasting Insecticidal Nets (LLIN) Long Lasting Insecticidal Nets (LLIN) Distribution of long lasting insecticidal nets to all community members in the study arm allowing for at least one net per 2 persons LLIN Plus Indoor Residual Spraying Indoor residual insecticide spraying (IRS) Distribution of long lasting insecticidal nets to all community members in the study arm allowing for at least one net per 2 persons plus indoor residual spraying with insecticide of interior walls of all houses twice yearly. LLIN Plus Indoor Residual Spraying Long Lasting Insecticidal Nets (LLIN) Distribution of long lasting insecticidal nets to all community members in the study arm allowing for at least one net per 2 persons plus indoor residual spraying with insecticide of interior walls of all houses twice yearly.
- Primary Outcome Measures
Name Time Method Malaria Incidence 3 years Infection with malarial parasites determined by rapid diagnostic tests/microscopy in cohort members who report or have fever (\>37.5C)
- Secondary Outcome Measures
Name Time Method Prevalence of P.falciparum Infection 3 years Infection with plasmodial parasites (falciparum and/or vivax) in randomly selected members of the study cohort in each study cluster during the peak of the malaria transmission season by rapid diagnostic test
Entomological Innoculation rate Average for months Sept, Oct, Nov for years 2011, 2012, 2013 Anopheles arabiensis mosquitoes collected in sentinel clusters by light trap, window trap, clay pot and pyrethrum sheet collection and determination of sporozoite, human blood index, feeding and resting behaviour.
Frequency of insecticide resistance associated genotypes (kdr) in anopheles arabiensis Yearly average 2011, 2012, 2013, 2014 Molecular analysis of mosquito specimens caught in subset of clusters by pyrethrum spray collection.
Trial Locations
- Locations (1)
Malaria Control Programme
🇸🇩Kassala, Kassala State, Sudan