Successful introgression of wMel Wolbachia into Aedes aegypti populations in Fiji, Vanuatu and Kiribati

PLoS Negl Trop Dis. 2024 Mar 14;18(3):e0012022. doi: 10.1371/journal.pntd.0012022. eCollection 2024 Mar.

Abstract

Pacific Island countries have experienced periodic dengue, chikungunya and Zika outbreaks for decades. The prevention and control of these mosquito-borne diseases rely heavily on control of Aedes aegypti mosquitoes, which in most settings are the primary vector. Introgression of the intracellular bacterium Wolbachia pipientis (wMel strain) into Ae. aegypti populations reduces their vector competence and consequently lowers dengue incidence in the human population. Here we describe successful area-wide deployments of wMel-infected Ae. aegypti in Suva, Lautoka, Nadi (Fiji), Port Vila (Vanuatu) and South Tarawa (Kiribati). With community support, weekly releases of wMel-infected Ae. aegypti mosquitoes for between 2 to 5 months resulted in wMel introgression in nearly all locations. Long term monitoring confirmed a high, self-sustaining prevalence of wMel infecting mosquitoes in almost all deployment areas. Measurement of public health outcomes were disrupted by the Covid19 pandemic but are expected to emerge in the coming years.

MeSH terms

  • Aedes* / genetics
  • Aedes* / microbiology
  • Animals
  • Dengue Virus*
  • Dengue*
  • Fiji / epidemiology
  • Humans
  • Mosquito Vectors / genetics
  • Mosquito Vectors / microbiology
  • Vanuatu
  • Wolbachia* / genetics
  • Zika Virus Infection*
  • Zika Virus*

Grants and funding

This work was supported by a grant award from the Commonwealth of Australia represented by the Department of Foreign Affairs and Trade titled; Operational pilot of Wolbachia technology to reduce the transmission of Aedes aegypti-borne diseases (“the Project”) awarded to SLO. The following authors received full or part salary from this grant for the work described here; WD, LT, TQ, RT, TN, EM, LK, TTA, VR, AT, WV, RP, ES, LN, AR, MH, NK, SCB, AGB, AM, MB, GW, LQD, JBB, DS, CF, NW, KR, PAR, JAD, RS, SKT, PK, YD, AK, LH. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.