Lab-scale characterization and semi-field trials of Wolbachia Strain wAlbB in a Taiwan Wolbachia introgressed Ae. aegypti strain

PLoS Negl Trop Dis. 2022 Jan 11;16(1):e0010084. doi: 10.1371/journal.pntd.0010084. eCollection 2022 Jan.

Abstract

Dengue fever is one of the most severe viral diseases transmitted by Aedes mosquitoes, with traditional approaches of disease control proving insufficient to prevent significant disease burden. Release of Wolbachia-transinfected mosquitoes offers a promising alternative control methodologies; Wolbachia-transinfected female Aedes aegypti demonstrate reduced dengue virus transmission, whilst Wolbachia-transinfected males cause zygotic lethality when crossed with uninfected females, providing a method for suppressing mosquito populations. Although highly promising, the delicate nature of population control strategies and differences between local species populations means that controlled releases of Wolbachia-transinfected mosquitoes cannot be performed without extensive testing on specific local Ae. aegypti populations. In order to investigate the potential for using Wolbachia to suppress local Ae. aegypti populations in Taiwan, we performed lab-based and semi-field fitness trials. We first transinfected the Wolbachia strain wAlbB into a local Ae. aegypti population (wAlbB-Tw) and found no significant changes in lifespan, fecundity and fertility when compared to controls. In the laboratory, we found that as the proportion of released male mosquitoes carrying Wolbachia was increased, population suppression could reach up to 100%. Equivalent experiments in semi-field experiments found suppression rates of up to 70%. The release of different ratios of wAlbB-Tw males in the semi-field system provided an estimate of the optimal size of male releases. Our results indicate that wAlbB-Tw has significant potential for use in vector control strategies aimed at Ae. aegypti population suppression in Taiwan. Open field release trials are now necessary to confirm that wAlbB-Tw mediated suppression is feasible in natural environments.

MeSH terms

  • Aedes / microbiology*
  • Animals
  • Biological Control Agents / administration & dosage
  • Dengue / prevention & control*
  • Dengue / transmission
  • Dengue Virus / isolation & purification
  • Female
  • Male
  • Mosquito Control / methods*
  • Mosquito Vectors / virology
  • Pest Control, Biological / methods*
  • Taiwan
  • Wolbachia / classification
  • Wolbachia / metabolism*
  • Zygote / microbiology

Substances

  • Biological Control Agents

Grants and funding

This study also was supported by the National Health Research Institutes (NHRI), Taiwan (grant no. NHRI-MR-110-GP-12) awarded to CHC. and (grant no. NHRI-MR-110-CO-03) awarded to ACCJ. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.