Study Results
The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.
Basic Information
Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.
COMPLETED
PHASE4
3302 participants
INTERVENTIONAL
2019-10-31
2020-06-30
Brief Summary
Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.
Detailed Description
Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.
The study will specifically assess the coverage and impact of interventions delivered at worksites to HRPs, including presumptive treatment administered alongside vector control interventions (indoor residual spraying \[IRS\], long-lasting insecticidal nets \[LLINs\], and topical repellents). The effectiveness of these interventions will be compared against areas with no study interventions (standard of care) over the course of implementation (November 2019 - May 2020). Primary outcomes will include the coverage of each intervention at worksites over the study period and PCR-based P. falciparum prevalence measured at endline. Following a baseline cross-sectional survey in November/December 2019, the interventions will consist of 2 rounds of presumptive treatment spaced at least one month apart between January and March, and delivery of vector control interventions at worksites and key access points with support from employers, with the primary evaluation to be conducted through an endline cross-sectional survey in April/May 2020. Secondary outcomes around effectiveness will be assessed through incident case data providing measures of incidence in HRP and non-HRP populations, odds of infection associated with each intervention in cases compared to controls and entomological data collection. In addition, operational and feasibility outcomes will be assessed through qualitative data collection, population size estimation of HRP groups and a global positioning system (GPS) logger study.
Conditions
See the medical conditions and disease areas that this research is targeting or investigating.
Study Design
Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.
RANDOMIZED
PARALLEL
TREATMENT
NONE
Study Groups
Review each arm or cohort in the study, along with the interventions and objectives associated with them.
Presumptive treatment and enhanced vector control
For all eligible HRPs in intervention areas, after obtaining informed consent, presumptive treatment for malaria will be carried out using artemether-lumefantrine (AL) at two time points.
Enhanced vector control activities will include: (1) a mop up indoor residual spraying (IRS) campaign and (2) distribution of long-lasting insecticide-treated nets (LLINs) and/or vector control packs with topical repellent.
The intervention arm will also receive the standard of care in Namibia.
Presumptive treatment with Artemether-lumefantrine (AL)
All eligible HRPs will be presumptively treated with artemether-lumefantrine (AL) at two timepoints, separated by at least one month. All individuals who have provided informed consent, meet eligibility criteria, are not pregnant or breastfeeding, and who do not have symptoms associated with severe malaria or another severe illness, will be offered an age-appropriate course of AL (age-specific blister packages). AL is currently the first line drug used for uncomplicated malaria in Namibia, and has been used previously in northern Namibia for focal mass drug administration and has no severe adverse effects and is well-tolerated, with high adherence and acceptability in this context. AL requires two daily doses for three consecutive days, for a total of six doses. The first antimalarial dose will be delivered by directly observed therapy (DOT) and subsequent doses will be left with the subject, with instructions to self-administer them.
Enhanced vector control
The mop up indoor residual spraying (IRS) campaign will be targeted to farms and cattle posts/kraals in intervention areas in December 2019 to fill gaps from the routine spray campaign (September to November 2019) and utilize the same insecticides and protocols as the national campaign. The team will spray each unsprayed structure with the recommended solution of dichloro-diphenyl-trichloroethane (DDT) for traditional structures and/or Actellic for modern structures, tarps and tents.
Alternative vector control interventions, including LLINs (long-lasting insecticide treated bed nets), sprayed tents/tarps and topical repellents will be distributed to eligible HRPs between November and January 2020 during one round.
Standard of care
The control arm will receive the standard of care in Namibia: passive case detection through health facilities and health extension workers, routine indoor residual spraying (IRS), and reactive case detection (RACD) accompanied by reactive IRS.
No interventions assigned to this group
Interventions
Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.
Presumptive treatment with Artemether-lumefantrine (AL)
All eligible HRPs will be presumptively treated with artemether-lumefantrine (AL) at two timepoints, separated by at least one month. All individuals who have provided informed consent, meet eligibility criteria, are not pregnant or breastfeeding, and who do not have symptoms associated with severe malaria or another severe illness, will be offered an age-appropriate course of AL (age-specific blister packages). AL is currently the first line drug used for uncomplicated malaria in Namibia, and has been used previously in northern Namibia for focal mass drug administration and has no severe adverse effects and is well-tolerated, with high adherence and acceptability in this context. AL requires two daily doses for three consecutive days, for a total of six doses. The first antimalarial dose will be delivered by directly observed therapy (DOT) and subsequent doses will be left with the subject, with instructions to self-administer them.
Enhanced vector control
The mop up indoor residual spraying (IRS) campaign will be targeted to farms and cattle posts/kraals in intervention areas in December 2019 to fill gaps from the routine spray campaign (September to November 2019) and utilize the same insecticides and protocols as the national campaign. The team will spray each unsprayed structure with the recommended solution of dichloro-diphenyl-trichloroethane (DDT) for traditional structures and/or Actellic for modern structures, tarps and tents.
Alternative vector control interventions, including LLINs (long-lasting insecticide treated bed nets), sprayed tents/tarps and topical repellents will be distributed to eligible HRPs between November and January 2020 during one round.
Other Intervention Names
Discover alternative or legacy names that may be used to describe the listed interventions across different sources.
Eligibility Criteria
Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.
Inclusion Criteria
* Identify primary occupation as a agricultural worker or cattle herder
* Zambezi Region: Have slept or worked outside at a farm or cattle post in the past 7 days or will do over the next 3 weeks (sleeping outside, working outside ploughing or guarding crops/cattle, or sleeping in any type of structure located at a farm or cattle post site)
* Ohangwena Region: Report overnight travel to Angola for grazing cattle during the malaria transmission season (November to May) Be willing and able to provide consent (ie mentally fit)
* In addition to the above, subjects must report travel outside of Namibia within the past 60 days to be eligible to receive AL.
* In addition to the above, participants must not sleep in a structure sprayed with insecticide to be eligible to receive an LLIN or sprayed tent/tarp.
* Meet eligibility criteria as a member of an HRP, health facility staff or health extension worker involved in the diagnosis and treatment of HRP populations.
* Individuals must be 18 years and older and willing and able to provide consent to be included in the GPS logger, focus group discussions or key informant interviews
Exclusion Criteria
* Individuals under the age of 18 will be excluded from the GPS logger study, focus group discussions and key informant interviews.
6 Months
ALL
Yes
Sponsors
Meet the organizations funding or collaborating on the study and learn about their roles.
University of Namibia
OTHER
Ministry of Health and Social Services, Namibia
OTHER_GOV
University of Texas Southwestern Medical Center
OTHER
University of Notre Dame
OTHER
London School of Hygiene and Tropical Medicine
OTHER
University of California, San Francisco
OTHER
Responsible Party
Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.
Principal Investigators
Learn about the lead researchers overseeing the trial and their institutional affiliations.
Jennifer Smith, PhD
Role: PRINCIPAL_INVESTIGATOR
University of California, San Francisco
Locations
Explore where the study is taking place and check the recruitment status at each participating site.
University of Namibia, Multidisciplinary Research Centre
Windhoek, , Namibia
Countries
Review the countries where the study has at least one active or historical site.
References
Explore related publications, articles, or registry entries linked to this study.
Jacobson JO, Cueto C, Smith JL, Hwang J, Gosling R, Bennett A. Surveillance and response for high-risk populations: what can malaria elimination programmes learn from the experience of HIV? Malar J. 2017 Jan 18;16(1):33. doi: 10.1186/s12936-017-1679-1.
Smith JL, Ghimire P, Rijal KR, Maglior A, Hollis S, Andrade-Pacheco R, Das Thakur G, Adhikari N, Thapa Shrestha U, Banjara MR, Lal BK, Jacobson JO, Bennett A. Designing malaria surveillance strategies for mobile and migrant populations in Nepal: a mixed-methods study. Malar J. 2019 May 3;18(1):158. doi: 10.1186/s12936-019-2791-1.
Smith JL, Auala J, Haindongo E, Uusiku P, Gosling R, Kleinschmidt I, Mumbengegwi D, Sturrock HJ. Malaria risk in young male travellers but local transmission persists: a case-control study in low transmission Namibia. Malar J. 2017 Feb 10;16(1):70. doi: 10.1186/s12936-017-1719-x.
Wu L, van den Hoogen LL, Slater H, Walker PG, Ghani AC, Drakeley CJ, Okell LC. Comparison of diagnostics for the detection of asymptomatic Plasmodium falciparum infections to inform control and elimination strategies. Nature. 2015 Dec 3;528(7580):S86-93. doi: 10.1038/nature16039.
Kern SE, Tiono AB, Makanga M, Gbadoe AD, Premji Z, Gaye O, Sagara I, Ubben D, Cousin M, Oladiran F, Sander O, Ogutu B. Community screening and treatment of asymptomatic carriers of Plasmodium falciparum with artemether-lumefantrine to reduce malaria disease burden: a modelling and simulation analysis. Malar J. 2011 Jul 29;10:210. doi: 10.1186/1475-2875-10-210.
Hsiang M, Ntuku H, Roberts K, Dufour M-s, Whittemore B, Tambo M, et al. The effectiveness of malaria reactive focal mass drug administration (rfMDA) and reactive vector control (RAVC), a cluster-randomised controlled two-by-two factorial design trial from the low-endemic setting of Namibi. 2019. Unpublished.
Initiative ME. Planning for targeted malaria interventions in high-risk populations (HRPs) in Northern Namibia: Findings from a rapid formative assessment in Zambezi Region. University of California, San Francisco, 2019.
The Global Health Group. Screen and treat strategies for malaria elimination: a review of evidence. 2018.
Malaria Elimination Initiative. Planning for targeted malaria interventions in high-risk populations (HRPs) in Northern Namibia: Findings from a rapid formative assessment in Ohangwena Region. University of California, San Francisco, 2019.
Naing C, Whittaker MA, Tanner M. Inter-sectoral approaches for the prevention and control of malaria among the mobile and migrant populations: a scoping review. Malar J. 2018 Nov 16;17(1):430. doi: 10.1186/s12936-018-2562-4.
IOM (International Organization for Migration). A global report on population mobility and malaria: moving towards elimination with migration in mind. 2013.
Smith JL, Ntuku H, Rerolle F, Burke AM, Mwema T, Turcios K, Uusiku P, Haikali JK, Lifasi M, Smith-Gueye C, Vajda E, Jacobson JO, Greenhouse B, Gosling R, Bennett A, Mumbengegwi DR. Targeting malaria in high-risk populations in low endemic regions in northern Namibia: a quasi-experimental controlled trial to reduce malaria in seasonal agricultural workers and cattle herders. BMJ Glob Health. 2025 Feb 17;10(2):e015565. doi: 10.1136/bmjgh-2024-015565.
Other Identifiers
Review additional registry numbers or institutional identifiers associated with this trial.
Malaria HRP in Namibia
Identifier Type: -
Identifier Source: org_study_id