Can insecticide-treated curtains prevent transmission of dengue?

ISRCTN ISRCTN08474420
DOI https://doi.org/10.1186/ISRCTN08474420
Secondary identifying numbers N/A
Submission date
14/04/2011
Registration date
18/04/2011
Last edited
07/03/2022
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

Pembroke Place
Liverpool
L3 5QA
United Kingdom

Phone +44 (0)151 705 3132
Email mccall@liv.ac.uk

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 indoor curtains for control of the dengue vector Aedes aegypti and prevention of transmission of dengue in the community
Study objectivesWe investigated whether window curtains made from long-lasting insecticide-treated netting and deployed inside houses, could reduce dengue virus transmission, as measured by seroconversion rates in humans, following reductions in dengue vector populations, as measured by a series of standard indices for Aedes aegypti intra-domiciliary and peri-domestic abundance, in intervention groups compared to control groups.
Ethics approval(s)1. Research Ethics Committee of the Liverpool School of Tropical Medicine approved on 8th June 2009 (ref: 09/59)
2. Loreto Regional Health (Direccion Regional de Salud de Loreto), Peru approved on 3rd July 2009 (ref 586-2009-GRL-DRS/30.09.01)
3. US Naval Medical Research Center Detachment (NAMRID) Lima approved on 8th September 2009 (project no. 6000 RAD1.S.B0302; Approval ref. NAVMEDRSCHCENDETACHMENTINST 3900.6H)
Health condition(s) or problem(s) studiedDengue (including Dengue Haemorrhagic Fever [DHF] and Dengue Shock Syndrome [DSS])
InterventionInsecticide-treated curtains deployed inside human habitations. The curtains are made from PermaNet® deltamethrin-coated polyester netting, a long-lasting impregnated material (Vestergaard-Frandsen, Lausanne, Switzerland), that has been approved for indoor use (World Health Organisation Pesticide Evaluation Scheme [WHOPES]), with proven efficacy against dengue vectors.

Householders in treated clusters are permitted to dictate the quantity and location of their insecticide-treated materials (ITMs), with a minimum of one ITM required for the household to be classified as receiving treatment.

Control households received no treatment, but will be offered ITMs at the end of the study.

Efficacy of the intervention (Insecticide-treated curtains as described in E51) fell to an unacceptably low level (as determined by standard WHO recommended bioassays and other methods), when monitored over a period of months during 2010. Consequently, in October and November 2010, the existing curtains were treated again with a different product ("K-O Tab 1 2 3"; Bayer Environmental Science, Germany) designed to deliver a long-lasting formulation of the same insecticide.
Intervention typeOther
Primary outcome measureEffect of ITMs on dengue transmission - measured by detection of dengue specific antibodies in human blood, taken from householders within the study area, using the Plaque Reduction Neutralizing Antibody test (PRNT). PRNT is specific to dengue virus serotype, and is the gold standard against which all other dengue virus (DV) serological assays are validated.

Blood samples will be collected from the study population at baseline and at three 9-month intervals thereafter (9, 18, 24 months post intervention) in householders that were not positive for all four circulating serotypes during the immediate preceding survey.
Secondary outcome measures1. The effect of ITMs on household vector infestation and breeding – primarily measured by:
1.1 The adult index (proportion of houses positive for adult Ae. aegypti)
1.2. The Breteau index (number of containers with immature vector stages/100 houses)
Secondarily by the other Stegomyia indices:
1.3. Pupae per person index (number of pupae per number of people)
1.4. House index (percentage of houses found with immature stages of Ae. aegypti)
1.5. Container index (percentage of water-holding containers found with immature stages of Ae. aegypti).
Six surveys will be conducted: Baseline and 1, 6, 12, 18 and 24 months post intervention.
2. Quantification of spill-over effects from treated clusters on nearby control clusters, a potential confounding effect on analyses as well as an indicator of potential community-level impact
3. Determining factors associated with adoption and continued use of ITMs, including the most effective diffusion mechanism (channel of communication) for ITM promotion, by household questionnaires and focus group discussions. Surveys will coincide with the serological surveys.
Overall study start date01/11/2009
Completion date31/12/2011

Eligibility

Participant type(s)Patient
Age groupAdult
SexBoth
Target number of participantsEstimated 9,200 participants from 1,400 households (based on 20 clusters of 70 houses/460 individual participants per cluster, 10 clusters per treatment arm)
Key inclusion criteria1. All occupied households
1.1. Persons aged 3 years or older with parental permission
1.2. Adults consenting to participate in the study living in the study area
1.3. Assent to participation for 8-17 year old persons
Key exclusion criteria1. Persons younger than 3 years old
2. Temporary visitors to the study areas
3. Adults who do not consent to participate
4. 8-17 year old persons who do not assent or who do not have parental permission to participate in the study
Date of first enrolment01/11/2009
Date of final enrolment31/12/2011

Locations

Countries of recruitment

  • England
  • Peru
  • United Kingdom

Study participating centre

Pembroke Place
Liverpool
L3 5QA
United Kingdom

Sponsor information

Liverpool School of Tropical Medicine (UK)
University/education

Pembroke Place
Liverpool
L3 5QA
England
United Kingdom

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

Funders

Funder type

Charity

The Wellcome Trust (UK) (grant ref: 085714)

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 planNot provided at time of registration

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Results article 07/03/2022 07/03/2022 Yes No

Editorial Notes

07/03/2022: Publication reference added.