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

ISRCTN ISRCTN52339690
DOI https://doi.org/10.1186/ISRCTN52339690
Secondary identifying numbers 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

Study designCluster-randomised controlled trial
Primary study designInterventional
Secondary study designRandomised controlled trial
Study setting(s)Other
Study typePrevention
Participant information sheet Not available in web format, please use the contact details below to request a patient information sheet
Scientific titleA 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 acronymDENCO Venezuela
Study objectivesWe 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) studiedDengue (including Dengue Haemorrhagic Fever [DHF] and Dengue Shock Syndrome [DSS])
InterventionCurtains 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 typeOther
Primary outcome measureEntomological 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).
Secondary outcome measures1. 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.
Overall study start date01/07/2006
Completion date31/10/2008

Eligibility

Participant type(s)Patient
Age groupOther
SexBoth
Target number of participants7,500 households
Total final enrolment1122
Key inclusion criteriaAll occupied households
Key exclusion criteria1. Business-only premises
2. Multi-storey buildings
Date of first enrolment01/07/2006
Date of final enrolment31/10/2008

Locations

Countries of recruitment

  • England
  • United Kingdom
  • Venezuela

Study participating centre

Liverpool School of Tropical Medicine
Liverpool
L3 5QA
United Kingdom

Sponsor information

Liverpool School of Tropical Medicine (UK)
Research organisation

Pembroke Place
Liverpool
L3 5QA
United Kingdom

Website http://www.lstmliverpool.ac.uk
ROR logo "ROR" https://ror.org/03svjbs84

Funders

Funder type

Government

European Union (EU) (Belgium) - Sixth Framework Programme (FP6): INCO-DEV-2 (ref: PL 517708)

No information available

The Wellcome Trust (UK) (grant ref: 075930)

No information available

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryNot provided at time of registration
Publication and dissemination planNot 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

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.