Malaria
Conditions
Keywords
falciparum, gametocyte, elimination, anopheles, transmission, diagnostic
Brief summary
In the current randomized trial, the investigators will test the ability of two experimental approaches to malaria infection management to reduce malaria transmission potential. Compounds in Saponé, Burkina Faso, will be randomized to 1 of 3 study arms: arm 1 - current standard of care with passively monitored malaria infections; arm 2 - standard of care plus enhanced community case management (CCM), comprising active weekly screening for fever, and detection and treatment of infections in fever positive individuals using conventional rapid diagnostic tests (RDTs); or arm 3 - standard of care and enhanced CCM, plus monthly screening and treatment (MSAT) using RDTs. The study will be conducted over approximately 18 months covering two high transmission seasons and the intervening dry season
Interventions
OTHEREnhanced Community Case Management (CCM)
Enhanced Community Case Management for malaria (CCM) involving weekly active screening for fever using a research-grade thermometer by a trained health worker. A measured temperature ≥37.5°C or reported fever in the last 24 hours will prompt screening with a conventional rapid diagnostic test (RDT). RDT positive individuals will be treated with AL according to national guidelines
OTHERMonthly Screening and Treatment (MSAT)
Monthly Screening and Treatment (MSAT) regardless of symptoms with a conventional RDT. Screening will be performed by research staff with 25-35 days between screening rounds; RDT positive individuals will be treated with AL according to national guidelines.
Sponsors
Centre national de recherche et de formation sur le paludisme
Radboud University Medical Center
Institute for Disease Modeling, Bellevue, US
London School of Hygiene and Tropical Medicine
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
NONE
Intervention model description
Cluster randomized trial
Eligibility
Sex/Gender
ALL
Healthy volunteers
Yes
Inclusion criteria
1. Participants should be permanent residents of the compound 2. Participants should be willing to participate in repeated assessments of health and infection status and willing to donate a maximum of 37mL of blood (children \<10 years of age) or 52mL of blood (older individuals) during an 18-month period
Exclusion criteria
1. Any (chronic) illness that would affect with study participation 2. Pre-existing severe chronic health conditions 3. Current participation in malaria vaccine trials or participation in such trials in the last 2 years 4. History of intolerance to artemether-lumefantrine
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Parasite prevalence and density by molecular detection at the end of study cross-sectional survey. | Month 18 (end of second transmission season; January-February 2020) | The primary outcome measure is parasite prevalence in the cross-sectional survey conducted at the end of the transmission season of year 2. If CCM and MSAT result in the early detection of infections, parasite prevalence at the end of the study will be lower in these arms compared to the control arm. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Parasite prevalence and density by molecular detection at the end of year 1 cross-sectional survey. | Month 6 (end of first transmission season; January-February 2019) | Parasite prevalence and density in the cross-sectional survey conducted at the end of the transmission season of year 1. If CCM and MSAT result in the early detection of infections, parasite prevalence will be lower in these arms compared to the control arm. |
| Parasite prevalence and density by molecular detection at the end of dry season cross-sectional survey. | Month 12 (prior to second transmission season; June 2019) | Parasite prevalence and density in the cross-sectional survey conducted at the end of the dry season. If CCM and MSAT result in the early detection of infections, parasite prevalence will be lower in these arms compared to the control arm. |
| Gametocyte prevalence and or density in P. falciparum infections at the end of study cross-sectional survey | Month 18 (end of second transmission season; January-February 2020) | Gametocyte prevalence in qPCR detected infections is assessed by molecular methods and compared between study arms. |
| Gametocyte prevalence and or density in P. falciparum infections at the end of year 1 cross-sectional survey | Month 6 (end of first transmission season; January-February 2019) | Gametocyte density of male and female gametocytes will be assessed by molecular methods and compared between study arms. |
| Gametocyte prevalence and or density in P. falciparum infections at the end of dry season cross-sectional survey | Month 12 (prior to second transmission season; June 2019) | Gametocyte density of male and female gametocytes will be assessed by molecular methods and compared between study arms. |
| Gametocyte prevalence and or density in P. falciparum during all study visits | Throughout study, an average of 18 months | Gametocyte density of male and female gametocytes will be assessed by molecular methods and compared between study arms. |
| The number of incident infections. | Throughout study, an average of 18 months | Regular visits by CCM and MSAT will result in the identification of malaria infections that are not detected during passive case detection. The numbers of infections that are detected in each arm are quantified and compared between arms. |
| Infectivity to mosquitoes of P. falciparum infections | Throughout study, an average of 18 months | For a selection of infections, infectiousness to mosquitoes is assessed by membrane feeding assays. |
Other
| Measure | Time frame | Description |
|---|---|---|
| The detectability of infections by highly sensitive rapid diagnostic tests. | Throughout study, an average of 18 months | For a selection of samples, the detectability of infections is assessed by conventional rapid diagnostic test and by highly sensitive rapid diagnostic tests and related to i. histidine rich protein-2 (HRP2) concentrations; ii. duration of infection; iii. parasite density by molecular diagnostics. |
| The relationship between the proportion of infected mosquitoes and gametocyte density. | Throughout study, an average of 18 months. | Gametocyte density and sex ratio will be assessed by molecular methods and associated with the proportion of infected mosquitoes and the burden of infection in mosquitoes |
| The impact of infection characteristics on the transmissibility of infections to mosquitoes | Throughout study, an average of 18 months. | Under this outcome, we aim to determine the impact of gametocyte sex-ratio, other gametocyte characteristics, duration of infection and clonal complexity of malaria infections on the transmissibility of infections to mosquitoes |
| The impact of human host characteristics on the transmissibility of infections to mosquitoes | Throughout study, an average of 18 months | Under this outcome, we aim to determine the impact of red blood cell haemoglobinopathies, haemoglobin concentration, inflammatory markers, naturally acquired antibody responses to gametocyte antigens and other host characteristics on the transmissibility of infections to mosquitoes |
| Association between total parasite density and gametocyte density | Throughout study, an average of 18 months | Under this outcome, we aim to evaluate the relationship between asexual parasite density and gametocyte density in P. falciparum infections |
| Malaria transmission potential based on measured gametocyte densities | Throughout study, an average of 18 months | Under this outcome, we aim to determine malaria transmission potential of infections based on the gametocyte density |
| Number of acquired clones based on genotyping | Throughout study, an average of 18 months | Under this outcome, we aim to examine the complexity of P. falciparum infection by measuring the number of clones present in infections |
| The duration of infections in the dry season | Month 6-12, between end of season survey January/February 2019 and end of dry season survey June 2019 | Under this outcome, we aim to evaluate the duration of P. falciparum carriage during the dry season |
| To quantify mosquito exposure in relation to incident infections | Throughout study, an average of 18 months | Under this outcome, we aim to quantify mosquito exposure and relate this to number of incident infections |
Countries
Burkina Faso
Outcome results
None listed