Can the presence of insecticide treated materials in the household control dengue vectors?

ISRCTN	ISRCTN52339690
DOI	https://doi.org/10.1186/ISRCTN52339690
Protocol serial number	075930
Sponsor	Liverpool School of Tropical Medicine (UK)
Funders	European Union (EU) (Belgium) - Sixth Framework Programme (FP6): INCO-DEV-2 (ref: PL 517708), The Wellcome Trust (UK) (grant ref: 075930)

Submission date: 17/03/2010
Registration date: 18/03/2010
Last edited: 19/02/2020

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Infections and Infestations

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Plain English summary of protocol

Not provided at time of registration

Contact information

Dr Philip McCall
Scientific

Liverpool School of Tropical Medicine
Liverpool
L3 5QA
United Kingdom

Study information

Primary study design	Interventional
Study design	Cluster-randomised controlled trial
Secondary study design	Randomised controlled trial
Study type	Participant information sheet
Scientific title	A cluster randomised controlled trial of household-based insecticide treated window curtains and water jar covers for control of the dengue vector Aedes aegypti in the community
Study acronym	DENCO Venezuela
Study objectives	We investigated whether window curtains and covers for domestic water storage containers, both made from long-lasting insecticide-treated netting and deployed either separately or in combination, could reduce populations of Aedes aegypti, the mosquito vector of dengue, to levels that could reduce dengue virus transmission in treated communities.
Ethics approval(s)	1. Research Ethics Committee of the Liverpool School of Tropical Medicine approved on the 2nd February 2006 (ref: 06/12) 2. Bio-ethical committee of the Jose Witremundo Torrealba Research Institute, Trujillo, Venezuela, approved on the 18th June 2006
Health condition(s) or problem(s) studied	Dengue (including Dengue Haemorrhagic Fever [DHF] and Dengue Shock Syndrome [DSS])
Intervention	Curtains made from deltamethrin-coated polyester netting (Long Lasting Impregnated netting; PermaNet® Vestergaard-Frandsen, Lausanne, Switzerland), hung in all outer windows regardless of the presence or absence of other window coverings (World Health Organization Pesticide Evaluation Scheme [WHOPES], approved material for indoor use). Insecticide-treated water storage container covers are provided as ready-to-use products (a pre-packaged standard size with elasticated border, to close round the water container rim). Treated households provided with enough covers for all large household receptacles that hold water for longer than 1 week (it is from these containers that most Aedes aegypti emerge). Control households received no treatment. Following introduction of ITMs, the total duration of both intervention and follow-up was 26 months.
Intervention type	Other
Primary outcome measure(s)	Entomological outcomes, the standard larval indices for the Aedes aegypti mosquito vector of dengue: 1. Breteau index: number of containers with immature stages per 100 houses 2. House index: number of houses containing immature stages per 100 houses 3. Container index: number of containers with immature stages per 100 containers with water 4. Pupal surveys were also undertaken to calculate the number of pupae per person index (number of pupae collected/human population in a sector) Follow up surveys made to all houses at 1, 18, 24, 26 months post-intervention. Analyses to measure impact of the intervention on dengue vector populations will be undertaken according to intention to treat and per protocol (based on extent of coverage as determined in follow-up surveys).
Key secondary outcome measure(s)	1. Seroconversion rates (as measured by IgM ELISA) in households in the treated and control sectors compared at baseline and at the trial's end. Members of each household between 2 - 8 years of age specifically selected for the study. 2. Interview surveys used to determine: 2.1. Household characteristics 2.2. Previous vector control intervention 2.3. Better understanding of the local population's knowledge, attitudes and practice about previous methods of dengue prevention and control, and about ITMs for the same purpose 3. Insecticide-susceptibility assays undertaken before, at follow-up surveys and after intervention Each house was also georeferenced with a handheld global positioning system receiver to permit subsequent overspill effects between adjacent treated and control clusters to be quantified.
Completion date	31/10/2008

Eligibility

Participant type(s)	Patient
Age group	Other
Sex	All
Target sample size at registration	7500
Total final enrolment	1122
Key inclusion criteria	All occupied households
Key exclusion criteria	1. Business-only premises 2. Multi-storey buildings
Date of first enrolment	01/07/2006
Date of final enrolment	31/10/2008

Locations

Countries of recruitment

United Kingdom
England
Venezuela

Study participating centre

Liverpool School of Tropical Medicine

Liverpool
L3 5QA
United Kingdom

Results and Publications

Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not provided at time of registration
IPD sharing plan

Study outputs

Output type	Details	Date created	Date added	Peer reviewed?	Patient-facing?
Results article	results	27/05/2006	19/02/2020	Yes	No
Participant information sheet	Participant information sheet	11/11/2025	11/11/2025	No	Yes

Editorial Notes

19/02/2020: The following changes have been made:
1. Publication reference added.
2. The final enrolment number has been added from the reference.