Reducing Filth Fly Populations and Transmission of Diarrhoeal Pathogens in Harsh Settings

ConditionDiarrheal Diseases

Trial statusRecruiting

Trial phasePhase 3

Trial typeInterventional

Biological sexAll

Age1+

SponsorThe Mentor Initiative

About this trial

Objectives The main trial objective is to evaluate the efficacy of larvicide (LARV) or baited fly traps (TRAP), or both interventions combined, on filth fly density and hence transmission of diarrhoeal diseases.

Primary Objective

• To evaluate the efficacy of LARV or TRAP, or both interventions combined, in reducing the number of cases of all-cause diarrhoea (primary epidemiological endpoint).

Secondary Objectives

* To evaluate the efficacy of LARV or TRAP, or both interventions combined, in reducing filth fly density and species composition at the latrine level (primary entomological endpoint). * To evaluate the efficacy of LARV or TRAP, or both interventions combined, in reducing filth fly density and species composition at the shelter level (secondary entomological endpoint).

Tertiary Objectives

* To assess the impact of LARV or TRAP, or both interventions combined, on enteric pathogen species composition and density (tertiary entomological endpoint). * To assess the impact of LARV or TRAP, or both interventions combined, on enteric pathogen antimicrobial resistance (AMR) prevalence (tertiary entomological endpoint).

Trial Design The proposed trial will be a 3-period, 3-group, interventional non-randomized cross-over trial with parallel control (Table 1). The unit of intervention will be an individual refugee camp. Each implementation phase will be 6 months, followed by a 1-month wash-out period.

The trial arms will be:

1. No intervention (control arm) 2. Dimilin® larvicide (intervention arm 1) 3. iCatchi® ProMax fly traps (intervention arm 2)

Eligibility criteria

This trial accepts healthy volunteers

Qualifiers

Individuals of either ≤5 years old or ≥15 years old all ages

Slept in camp ≥27 nights during any given month

Individual is not severely malnourished, sick, anemic (self-reported), has signs of clinical decompensation, and/or has any other chronic co-morbidities (e.g. HIV or cancer)

No plans for extended travel (>1 month) outside of camp during study

Disqualifiers

Child < 1 years old (due to breastfeeding) or aged >5 and <15 years old

Slept in camp <27 nights during any given month

Individual is severely malnourished, sick, anemic, has signs of clinical decompensation, and/or has any other chronic co-morbidities (e.g. HIV or cancer)

Plans for extended travel (>1 month) outside of camp during study

Trial design

Design model

Crossover

Treatments tested in this trial

Baited fly traps - iCatchi® ProMax fly traps
Other intervention
iCatchi® ProMax fly traps are 10 L containers which hold 3 L of proprietary fly bait, formulated to maximize fly attractiveness to ensure high capture rates. The container design minimizes spillage and allows for easy set up and maintenance in different environments, including agricultural settings, waste management sites and urban areas. Each TRAP requires re-baiting every 8 weeks. TRAP will be placed on the ground outdoors and flies enter the large black container through rectangular holes between the bait bowl and larger trap chamber and are unable to exit; they will eventually die from starvation / dehydration.
Insect growth regulator (IGR) - effervescent granule containing 2% diflubenzuron (20g/kg)
Other intervention
This intervention will interrupt filth fly development at the larval / pupal stage, to reduce overall population density. All eligible pit latrines (with at least 3 standing walls) assigned to this intervention arm will be treated with Dimilin® GR-2 at 0.5 kg/10m2; granules will be sprinkled onto damp sewage per pit latrine. If waste is desiccated, this intervention will be diluted in water and applied as a spray. This intervention will be re-applied to pit latrines and open defecation sites, every month during each 6-month implementation phase.

Treatment groups

5,556 Participants

are divided into 3 treatment groups

Group A: ControlNo intervention 0 interventions

Group B: Mass deployment of baited fly traps next to pit latrines in refugee campsExperimental treatment 1 intervention

Group C: Insecticide growth regulator treatment of faeces in pit latrines / open defecation sitesExperimental treatment 1 intervention

Trial outcomes

Primary outcomes

Impact of larvicide (LARV) or baited fly traps (TRAP), or both interventions combined, in reducing the number of cases of all-cause diarrhoea (primary epidemiological endpoint).

The primary outcome will be all-cause diarrhoeal case incidence in children ≤5 and individuals ≥15 years. A diarrhoeal case is defined by WHO as the passage of 3 or more loose or liquid stools per day (or more frequent passage than is normal for the individual). Epidemiological data will be collected from 2 sources during baseline and each of 3 implementation phases. We will collect information on 1) diarrhoea incidence from local health facilities; and 2) shelter level diarrhoea incidence using fortnightly surveys. Passive surveillance data on diarrhoeal cases from camp residents will be obtained from the nearby health facilities. Permission will be sought from these facilities during trial baseline, and fortnightly data will be collected during each 6-month implementation phase.

Time frame