P. Falciparum Infection Dynamics and Transmission to Inform Elimination

Not Applicable

• Conditions: Malaria

• Registration Number: NCT04053907
• Lead Sponsor: London School of Hygiene and Tropical Medicine

Brief Summary

In the current study, three experimental approaches aiming at reducing malaria transmission will be tested. The study will cover two transmission season (2019 and 2020) and the interventions will vary by season. More specifically, in the 2019 transmission season (June-December) (Year 1), community case management of malaria (CCM) will be implemented in all eight villages as improved standard of care; in the 2020 transmission season (Year 2), the eight study villages will be divided into 4 study arms. CCM will continue in all villages; two villages will continue with CCM only (Arm 1, control); the three other pairs of villages will receive active fever screening and treatment (Arm 2); monthly mass screening and treatment (MSAT) (Arm 3); and mass drug administration (MDA) during the last 3 months of the dry season (April-June) (Arm 4). For MDA, the whole population (except for those not fulfilling the entry criteria) will be treated with a full course of dihydroartemisinin-piperaquine (DP) (320/40mg and 160/20mg piperaquine/ dihydroartemisinin per tablet) per manufacturer's guidelines (once daily for 3 days and according to body weight). The MDA treatment will be repeated 3 times at monthly intervals.

Detailed Description

In the current study, the investigators will first improve access to care in all villages by implementing community-based clinical case management (CCM) (year 1). In this year, the investigators will quantify gametocyte carriage and transmission from clinical cases passively recruited by CCM, and gametocyte carriage and transmission from asymptomatic infections detected in community surveys. These data will support the interpretation of the main study outcomes in year 2 when the investigators will directly compare the effect of CCM on the human reservoir of infection as compared to three different approaches, namely i) active fever screening and treatment that should detect symptomatic infections for early treatment; ii) Mass Screening and Treatment (MSAT) that will systematically screen, using point-of-care diagnostics, the whole population, with infected individuals immediately treated; and iii) mass drug administration (MDA) that will treat the whole population with a full course of an antimalarial treatment.

Study Timeline

• Study First Submitted: 2019-07-29
• Study First Submitted QC: 2019-08-08
• Study First Posted: 2019-08-13
• Study Start: 2019-08-15
• Status Verified: 2022-03
• Last Update Submitted: 2022-03-25
• Last Update Posted: 2022-03-31
• Primary Completion: 2022-05-31
• Study Completion: 2022-05-31

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 4000

Inclusion Criteria

1. Resident in the village.
2. Willingness to participate in repeated assessments of health and infection status and to donate a maximum of 30 mL (milliliter) of blood (children <5 years of age), 37 mL (milliliter) of blood (children <10 years of age) or 52 mL (milliliter) of blood (older individuals) during an 18-month period.

Exclusion Criteria

1. Any chronic illness that would affect study participation.
2. Pre-existing severe chronic health conditions
3. History of intolerance to artemether-lumefantrine.
4. Participants < 6months old and pregnant women in the first trimester (only for Arm with MDA-DP treatment).
5. Hypersensitivity to DP (only for Arm with MDA-DP treatment).
6. Taking drugs that influence cardiac function or prolong QTcorrected interval (only for Arm with MDA-DP treatment).

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Parasite prevalence by molecular detection at the end of study (cross-sectional survey).	16 weeks	The primary outcome measure is parasite prevalence in the cross-sectional survey conducted at the end of the transmission season of year 2.
Parasite density by molecular detection at the end of study (cross-sectional survey).	16 weeks	The primary outcome measure is parasite density (parasite/µL) in the cross-sectional survey conducted at the end of the transmission season of year 2.

Secondary Outcome Measures

Name	Time	Method
Gametocyte prevalence by molecular methods at the end of study (cross-sectional survey).	16 weeks	Gametocyte prevalence in quantitative polymerase chain reaction (qPCR) detected infections is assessed by molecular methods and compared between arms.
Gametocyte density by molecular methods at the end of study (cross-sectional survey).	16 weeks	Gametocyte density (gametocytes/µL) in qPCR detected infections is assessed by molecular methods and compared between arms.
Gametocyte prevalence of male and female gametocytes by molecular methods among P. falciparum infections at all study visits.	Throughout study, an average of 18 months	Gametocyte prevalence of male and female gametocytes will be assessed by molecular methods and compared between study arms.
Incidence of malaria infections	Throughout study, an average of 18 months	Regular visits by weekly active case detection and monthly screening will result in the identification of malaria infections that are not detected during CCM. Number of infections detected in each arm will be quantified and compared between arms.
Infectivity of P. falciparum infections to mosquitoes	Throughout study, an average of 18 months	For a selection of infections, infectiousness to mosquitoes is assessed by membrane feeding assays.
Gametocyte density of male and female gametocytes by molecular methods among P. falciparum infections at 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.

Trial Locations

Locations (1)

Medical research Council Unit The Gambia at LSHTM; 🇬🇲 Basse Santa Su, Gambia