Impact of Project Wolbachia - Singapore on Dengue Incidence

Dengue Clinical Trial

Official title:

Assessing the Efficacy of Male Wolbachia-infected Mosquito Deployments to Reduce Dengue Incidence in Singapore: a Cluster Randomized Controlled Trial

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT05505682
• Other study ID #: IRB024
• Status: Recruiting
• Phase: N/A
• Start date: July 28, 2022
• Est. completion date: January 2025

Study information

• Verified date: November 2023
• Source: National Environment Agency, Singapore
• Contact: Lee Ching Ng, PhD
• Phone: +65 67719108
• Email: NG_Lee_Ching[@]nea.gov.sg
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The study is a cluster-randomised controlled trial set in Singapore, to assess if the deployment of male Wolbachia-infected Aedes aegypti mosquitoes can reduce dengue incidence in intervention clusters.

Description:

The study is designed as a parallel, two-arm, non-blinded cluster-randomised controlled trial to be conducted in high-rise public housing estates in Singapore. The aim is to determine whether large-scale deployment of male Wolbachia-infected Ae. aegypti mosquitoes can significantly reduce dengue incidence in intervention clusters. The investigators will use the cluster-randomised design, with the study area comprising 15 clusters with a total area of 10.9 km2, covering approximately 722,000 residents in 1,700 apartment blocks. Eight clusters will be randomly selected to receive the intervention, while the other seven will serve as non-intervention clusters. Intervention efficacy will be estimated through two primary endpoints: (1) odds ratio of Wolbachia exposure distribution (i.e. probability of living in an intervention cluster) among laboratory-confirmed reported dengue cases compared to test-negative controls, and (2) laboratory-confirmed reported dengue counts normalized by population size in intervention versus non-intervention clusters.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 2000
• Est. completion date: January 2025
• Est. primary completion date: September 2024
• Accepts healthy volunteers: No
• Gender: All
• Age group: N/A and older

Eligibility

Inclusion criteria:

• Dengue-suspected patients living in the intervention and non-intervention clusters whose blood samples are collected by a national network of diagnostic laboratories that support private clinics, public polyclinics, or public/private hospitals.

• Test positive cases: Patients with virologically confirmed DENV infection through RT-qPCR, testing positive for NS1 antigen or IgM. A positive test for any of the three assays would classify the patient as a dengue case.

• Test negative controls: Patients with negative test results for DENV through RT-qPCR, NS1 antigen ELISA, or DENV IgM.

Related Conditions & MeSH terms

• Dengue

Intervention

Biological:
• Biological (Male Wolbachia-infected Aedes aegypti)
Releases of male Wolbachia-infected Aedes aegypti mosquitoes

Locations

Country	Name	City	State
Singapore	National Environment Agency	Singapore

Sponsors (2)

Lead Sponsor	Collaborator
National Environment Agency, Singapore	Ministry of Health, Singapore

Country where clinical trial is conducted

Singapore, 

References & Publications (2)

Anders KL, Indriani C, Ahmad RA, Tantowijoyo W, Arguni E, Andari B, Jewell NP, Rances E, O'Neill SL, Simmons CP, Utarini A. The AWED trial (Applying Wolbachia to Eliminate Dengue) to assess the efficacy of Wolbachia-infected mosquito deployments to reduce dengue incidence in Yogyakarta, Indonesia: study protocol for a cluster randomised controlled trial. Trials. 2018 May 31;19(1):302. doi: 10.1186/s13063-018-2670-z. — View Citation

Utarini A, Indriani C, Ahmad RA, Tantowijoyo W, Arguni E, Ansari MR, Supriyati E, Wardana DS, Meitika Y, Ernesia I, Nurhayati I, Prabowo E, Andari B, Green BR, Hodgson L, Cutcher Z, Rances E, Ryan PA, O'Neill SL, Dufault SM, Tanamas SK, Jewell NP, Anders KL, Simmons CP; AWED Study Group. Efficacy of Wolbachia-Infected Mosquito Deployments for the Control of Dengue. N Engl J Med. 2021 Jun 10;384(23):2177-2186. doi: 10.1056/NEJMoa2030243. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Odds ratio of Wolbachia exposure distribution among laboratory-confirmed reported dengue cases compared to test-negative controls	Dengue cases and dengue test-negative controls data will be obtained from the national surveillance network of diagnostic laboratories which receive samples for dengue testing.	Up to 3 years
Primary	Laboratory-confirmed reported dengue case counts normalized by population size in intervention versus non-intervention clusters	Dengue cases data will be obtained from the national surveillance network of diagnostic laboratories which receive samples for dengue testing.	Up to 3 years
Secondary	Prevalence of Ae. aegypti/Ae. albopictus mosquitoes	Data will be obtained from the national gravitrap surveillance system	Up to 3 years
Secondary	Public Attitudes, Perceptions & Knowledge (APK) of Wolbachia and other vector control interventions	Sentiment surveys pre-trial and during the course of the trial, using true/false and Likert-type scales. Higher scores mean better outcomes.	Up to 3 years