Wolbachia Mosquito Release for Dengue Fever

No longer recruiting at 1 trial location

Overseen By Srilatha Edupuganti

Age: < 18

Sex: Any

Trial Phase: Academic

Sponsor: National Institute of Allergy and Infectious Diseases (NIAID)

Disqualifiers: Moving, Poor venous access, Vaccines, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: Unknown

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests whether releasing special mosquitoes can help reduce dengue fever in Brazil. These mosquitoes carry Wolbachia, a bacterium that makes it harder for them to spread the virus causing dengue and other similar illnesses. The trial compares areas where Wolbachia-infected Aedes aegypti mosquitoes are released with places that only use standard mosquito control measures. Children aged 6-11 who attend selected public schools and live nearby most of the week may be eligible to participate. As an unphased trial, this study offers participants a chance to contribute to innovative research that could lead to new methods of controlling dengue fever.

Do I have to stop taking my current medications for the trial?

The trial information does not specify whether participants need to stop taking their current medications. It seems unlikely that you would need to stop, but it's best to check with the trial organizers for confirmation.

What prior data suggests that the release of Wolbachia-infected Aedes aegypti mosquitoes is safe?

Research shows that mosquitoes carrying Wolbachia bacteria are safe for people and the environment. Studies have found that releasing these mosquitoes poses minimal risk to humans. The Wolbachia bacteria make it harder for mosquitoes to spread dengue fever, providing a significant benefit. These bacteria can also be passed on to future generations of mosquitoes, extending the positive effects. So far, no negative effects on humans have been reported from using these mosquitoes. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about Wolbachia-infected Aedes aegypti mosquitoes because they represent a groundbreaking approach to controlling dengue fever. Unlike traditional methods that rely on insecticides or vaccines, this technique uses mosquitoes infected with Wolbachia bacteria, which reduces the mosquitoes' ability to transmit the dengue virus. This method is innovative as it aims to naturally suppress the mosquito population's capacity to spread the virus, potentially offering a sustainable and environmentally friendly alternative to chemical-based vector control measures.

What evidence suggests that releasing Wolbachia-infected mosquitoes is effective for reducing dengue fever?

Research has shown that releasing mosquitoes infected with Wolbachia bacteria can greatly reduce the spread of dengue fever. Studies have found up to a 96% drop in dengue cases after introducing these mosquitoes. In one study in Indonesia, researchers observed a 77% decrease in dengue cases and an 86% reduction in hospitalizations. The Wolbachia bacteria make it harder for mosquitoes to carry and spread the virus, effectively working against all four types of dengue viruses. In this trial, one group will be exposed to Wolbachia-infected Aedes aegypti mosquitoes alongside standard vector control efforts, while the control group will receive only standard vector control efforts. Overall, using Wolbachia-infected mosquitoes offers a promising way to fight dengue fever. ^{1 3 5 6 7}

Are You a Good Fit for This Trial?

This trial is for children aged 6-11 who attend selected public schools within the study areas in Brazil. They must live there at least 5 days a week and have consent from a parent or guardian, as well as provide their own assent to participate.

Inclusion Criteria

I am between 6 and 11 years old.

Child is enrolled in a public school selected for this trial (and which define the clusters).

Child's parent or legal guardian agrees to provide written informed consent.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Establishment Stage

Deployment of Wolbachia-infected Aedes aegypti mosquitoes in intervention clusters

4 months

Consolidation Stage

Measurement of Wolbachia prevalence and remedial deployments to achieve high prevalence

8 months

Follow-up

Monitoring of Wolbachia prevalence and sero-incidence of ARBV infection

Year 1 through Year 5

What Are the Treatments Tested in This Trial?

Interventions

• Wolbachia-infected Aedes aegypti

Trial Overview The trial tests if releasing Wolbachia-infected Aedes aegypti mosquitoes into the environment can reduce dengue fever infections when combined with standard control measures, compared to using standard measures alone over three to four years.

How Is the Trial Designed?

Group I: Intervention Experimental Treatment 2 Interventions

29 school-based clusters of healthy individuals, age 6-11, exposed to standard vector control efforts recommended by the Brazilian National Dengue Control Program (PNCD) and Wolbachia-infected Aedes aegypti (wMel) mosquitoes. n=1740

Group II: Control Active Control 1 Intervention

29 school-based clusters of healthy individuals, age 6-11, exposed to standard vector control efforts recommended by the Brazilian National Dengue Control Program (PNCD). n=1740

Who Is Running the Clinical Trial?

National Institute of Allergy and Infectious Diseases (NIAID)

Lead Sponsor

Trials

3,361

Recruited

5,516,000+

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC11005084/

Wolbachia‐carrying Aedes mosquitoes for preventing dengue ... An analysis of case DENV notifications data prior to and after mosquito deployments indicated a 96% reduction in dengue incidence in Wolbachia‐ ...

2. worldmosquitoprogram.org worldmosquitoprogram.org/en/work/wolbachia-method/impact

Impact A gold-standard randomised controlled trial in Yogyakarta, Indonesia showed a 77% reduction in dengue and 86% reduction in dengue hospitalisations in Wolbachia- ...

3. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8297942/

Effectiveness of Wolbachia-infected mosquito deployments in ... The introduction of the bacterium Wolbachia (wMel strain) into Aedes aegypti mosquitoes reduces their capacity to transmit dengue and other arboviruses.

4. nejm.org nejm.org/doi/full/10.1056/NEJMoa2030243

Efficacy of Wolbachia-Infected Mosquito Deployments for ... The protective efficacy of the intervention was 77.1% (95% CI, 65.3 to 84.9) and was similar against the four dengue virus serotypes. The ...

5. sciencedirect.com sciencedirect.com/science/article/pii/S2052297525000162

Wolbachia: A bacterial weapon against dengue fever Field experiments have shown that introducing Wolbachia-infected mosquitoes can effectively reduce mosquito populations and lower dengue transmission rates, ...

6. worldmosquitoprogram.org worldmosquitoprogram.org/en/work/wolbachia-method/how-it-works

How WMP's Wolbachia method works Wolbachia is safe for humans and the environment. Independent risk analyses indicate that the release of Wolbachia mosquitoes poses negligible risk to humans ...

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC7403856/

a quasi-experimental trial using controlled interrupted time ... Results: Rapid and sustained introgression of wMel Wolbachia into local Ae. aegypti populations was achieved. Thirty-four dengue cases were notified from the ...