Reducing Filth Fly Populations and Transmission of Diarrhoeal Pathogens in Harsh Settings: a Cross-over Trial in South Sudan
试验速览
- 阶段
- 3 期
- 状态
- 招募中
- 入组人数
- 5,556
- 试验地点
- 2
- 主要终点
- 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).
研究概览
简要总结
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:
- No intervention (control arm)
- Dimilin® larvicide (intervention arm 1)
- iCatchi® ProMax fly traps (intervention arm 2)
详细描述
Study Setting This study will take place in Maban County, Upper Nile State, South Sudan, which is home to 4 refugee camps. Many refugees originate from Sudan and others from Ethiopia, Eritrea, and Somalia. The 4 camps host 218,439 refugees (104,784 in Doro, 57,605 in Yusuf Batil, 34,914 in Kaya and 21,136 in Gendrassa), according to the UN High Commissioner for Refugees (UNHCR) population estimates from 30 November 2025.
The refugee camps shelters are constructed from a mix of locally sourced materials. Most are temporary shelters made from tarpaulin and plastic sheeting, but some use a mixture of wood, mud, thatch and corrugated iron. The latrines primarily comprise polypropylene sheeting suspended by wooden sticks, with an open roof. They are rudimentary and built to be easily replaceable in case of flooding. Camps are designed with a set ratio of latrines to family shelters.
According to recent District Health Information Systems data, the major causes of death among refugee children arriving to the camps are measles and malnutrition. Malaria remains the leading cause of morbidity and mortality, accounting for 66% of outpatient consultations, 30% of admissions and 50% of deaths. Diarrhoeal diseases affect all refugee age groups but are worse among those under 5s, attributable to 10% of deaths in this age group.
Age Eligibility Criteria: See "Eligibility"
Arms and Interventions: See "Arms and Interventions"
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Crossover
- 主要目的
- Prevention
- 盲法
- Single (Outcomes Assessor)
盲法说明
DSMB committee Trial Steering Committee NB: these committees can request unblinding of data if they have serious concerns regarding adverse event monitoring.
入排标准
- 年龄范围
- 1 Year 至 —（Child, Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •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
- •Resides in an easily accessible dwelling and is present at time of enrolment
- •Not participating in another clinical trial investigating a vaccine, drug, medical device, or a medical procedure during the trial
- •Provision of informed consent form signed by the parent(s) or guardian (≤5s), able to give informed consent as an adult or able to give informed assent for children ≥15 years
排除标准
- •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
- •Not present at time of enrollment
- •Participating or planning to participate in another clinical trial investigating a vaccine, drug, medical device, or a medical procedure during the trial
- •No provision of informed consent form signed by the parent(s) or guardian (≤5s), unable to give informed consent as an adult or unable to give informed assent for children ≥15 years
研究组 & 干预措施
Control
Insecticide growth regulator treatment of faeces in pit latrines / open defecation sites
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.
干预措施: Insect growth regulator (IGR) - effervescent granule containing 2% diflubenzuron (20g/kg) (Other)
结局指标
主要结局
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).
时间窗: At trial baseline and then every fortnight during each of three 6-month intervention phases.
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.
To evaluate the efficacy of insecticidal paint (PAINT) or insect growth regulator (LARV), or both interventions combined, in reducing the number of cases of all-cause diarrhoea (primary epidemiological endpoint).
时间窗: At trial baseline and then every fortnight during each of three 6-month intervention phases.
The primary outcome will be all-cause diarrhoeal case incidence in children \<5 and individuals \>15. 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 bi-weekly 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 bi-weekly data will be collected during each 6-month implementation phase.
次要结局
- Impact of LARV or TRAP, or both interventions combined, on filth fly density - latrine level(At trial baseline and then every fortnight during each of three 6-month intervention phases.)
- Impact of LARV or TRAP, or both interventions combined, on filth fly species composition - latrine level(At trial baseline and then every fortnight during each of three 6-month intervention phases.)
- Impact of LARV or TRAP, or both interventions combined, on filth fly species density - shelter level(At trial baseline and then every fortnight during each of three 6-month intervention phases.)
- Impact of LARV or TRAP, or both interventions combined, on filth fly species composition - shelter level(At trial baseline and then every fortnight during each of three 6-month intervention phases.)
- Filth fly density and species composition(At trial baseline and then every fortnight during each of three 6-month intervention phases.)
- Filth fly species composition - latrine level(At trial baseline and then every fortnight during each of three 6-month intervention phases.)
- Filth fly species density - shelter level(At trial baseline and then every fortnight during each of three 6-month intervention phases.)
- Filth fly species composition - shelter level(At trial baseline and then every fortnight during each of three 6-month intervention phases.)