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

Summary

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)

Conditions

• Diarrheal Diseases

Interventions

OTHER

Baited fly traps - iCatchi® ProMax fly traps

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.

OTHER

Insect growth regulator (IGR) - effervescent granule containing 2% diflubenzuron (20g/kg)

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.

Sponsors & Collaborators

• University of Nevada, Las Vegas

  collaborator OTHER

• The Mentor Initiative

  lead OTHER

Principal Investigators

• Richard James Allan, PhD · The Mentor Initiative

Study Design

Allocation

NON_RANDOMIZED

Purpose

PREVENTION

Masking

SINGLE

Model

CROSSOVER

Eligibility

Min Age

1 Year

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2026-08-17

Primary Completion

2027-10-31

Completion

2027-12-19

Countries

• South Sudan

Study Locations