Testing Combined IIT-SIT to Control Mosquito-Borne Diseases At Scale
- Conditions
- DengueZikaChikungunya
- Interventions
- Genetic: Wolbachia induced incompatible matingCombination Product: Standard traditional chemical mosquito control
- Registration Number
- NCT06595745
- Lead Sponsor
- Michigan State University
- Brief Summary
Mosquito-borne diseases cause suffering for hundreds of millions of people and claim more than 700,000 lives yearly. Diseases such as dengue, Zika, and chikungunya cause symptoms similar to malaria and are endemic in many parts of the world, yet there are no treatments for them nor vaccines for Zika and chikungunya. Mosquito control, particularly of the Aedes aegypti species, is seen as a potentially effective solution to slow or stop the spread of these diseases but has not yet demonstrated significant, sustainable impacts on disease transmission. The investigators will aim to significantly control or eliminate local foci (hot-spots) of dengue, chikungunya and Zika transmission and significantly reduce disease transmission by implementing a combined incompatible and sterile insect technique (IIT-SIT) program based on the release of male Aedes aegypti carrying Wolbachia (wAlbB strain) that have been previously irradiated with X-rays (to minimize the chance of fertile female releases). The investigators will implement a two-arm cluster randomized controlled trial to evaluate the epidemiological and entomological impact of population suppression via IIT-SIT on Aedes-borne diseases in the city of Merida, Mexico. Primary endpoint of the trial is the incidence of laboratory Aedes-borne viruses detected by the passive surveillance system of Mexico. Secondary endpoints will allow estimating the level of suppression of Ae. aegypti populations. This trial design will allow establishing a link between epidemiologic, entomo-virological and entomological indicators to determine the effectiveness of IIT-SIT in real world conditions. The approach is novel because it effectively eliminate vectors, such as urban, outdoor, daytime biting mosquitoes, which are not susceptible to standard vector control approaches, by targeting cryptic and inaccessible mosquito habitats. In addition, the intervention has the below advantages comparing to existing alternatives: (i) highly competitive males are used for release as Wolbachia-infected males have the mating competitiveness equal to wild-type males; (ii) release can continue until population elimination is reached as a low dose of radiation is used to sterilize females for preventing risk of population replacement; (iii) any residual females contaminated in released male pools is resistant to pathogens; (iv) public acceptance of release of Wolbachia-infected males can be easily achieved, because Wolbachia are bacteria naturally presenting in \~50 percent of insect species, and male mosquitoes neither bite nor transmit diseases and can be self-limiting post release; (v) it will not impact non-target species. Successful findings from this study will pave the way for future expansions of the combined IIT-SIT to the entire city and nationwide using a rolling-carpet strategy, which has been successfully demonstrated for area-wide control of screwworm and medfly in Latin America.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- ACTIVE_NOT_RECRUITING
- Sex
- All
- Target Recruitment
- 15243
- All residents in the release sites will be included in the studies
- No exclusion will be performed.
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Release sites Wolbachia induced incompatible mating Traditional mosquito control will be applied, followed by weekly release of Wolbachia wAlbB-infected Aedes aegypti males to induce sterile mating with wild female mosquitoes. Release sites Standard traditional chemical mosquito control Traditional mosquito control will be applied, followed by weekly release of Wolbachia wAlbB-infected Aedes aegypti males to induce sterile mating with wild female mosquitoes. Control sites with traditional mosquito control only Standard traditional chemical mosquito control Traditional mosquito control will be applied but no mosquito release will occur in the control sites
- Primary Outcome Measures
Name Time Method Epidemiological impact of combined IIT-SIT Up to 19 months Incidence of symptomatic Aedes-borne virus (dengue, chikungunya, Zika) confirmed by laboratory testing by the Yucatan Ministry of Health.
- Secondary Outcome Measures
Name Time Method Entomological impact of combined IIT-SIT Up to 19 months Number of Aedes aegypti females infected with dengue, chikungunya or Zika virus (quantified as minimum infection rate, MIR); Number of Aedes aegypti females collected indoors (during 10-minute collections) using Prokopack aspirators; Number of Aedes aegypti females collected in the peridomicile with BG-sentinel traps.
Trial Locations
- Locations (1)
Laboratorio para el Control Biolo´gico de Aedes aegypti (LCB-UADY), Universidad Autónoma de Yucatán
🇲🇽Merida, Yucatan, Mexico