Written Reply to Parliamentary Question on Project Wolbachia

Question:

Gerald Giam Yean Song: To ask the Minister for Sustainability and the Environment (a) how many reports of biting by male Wolbachia mosquitoes have been received since 2024; (b) what is the current error rate for the sex-sorting process for Project Wolbachia; and (c) what scientific evidence ensures that these released male mosquitoes lack the physiological capability to bite or draw blood from humans.

Answer:

We have not received any report of biting by male Wolbachia mosquitoes. Residents in Project Wolbachia sites may still experience mosquito bites from female mosquitoes of species that are found locally, including those not released by Project Wolbachia. Source reduction efforts, therefore, remain important in suppressing the mosquito population.

Through our rigorous laboratory studies and quality control checks, we found that the sex-sorting process for Project Wolbachia achieved an accuracy of 99.9%. The small number of female Wolbachia mosquitoes inadvertently released is negligible compared to the overall mosquito population in the community, and these females have significantly reduced ability to transmit diseases. Neighbourhoods where male Wolbachia mosquitoes have been released have seen an 80% reduction in female Aedes aegypti mosquito populations and more than 70% reduction in dengue risk.

NEA has thoroughly studied the Wolbachia-Aedes suppression technology and conducted independent risk assessments, concluding that it is safe and poses no risk to human health. This conclusion is supported by international research and independent reviews.