Wolbachia-Aedes Mosquito Suppression Strategy

How Does Wolbachia-Aedes Suppression Technology Work?

How does releasing male Wolbachia-Aedes mosquitoes suppress Aedes aegypti populations?

  • When male Wolbachia-carrying Aedes aegypti (Wolbachia-Aedes) mosquitoes mate with urban female Aedes aegypti that do not carry Wolbachia, their resulting eggs do not hatch.

Diagram on Wolbachia-Aedes suppression technology

  • Over time, continued releases of male Wolbachia-Aedes mosquitoes will lead to a decline in urban Aedes aegypti populations. This not only reduces the risk of dengue, but also of other Aedes aegypti-borne diseases such as Zika and chikungunya. 

The science behind Wolbachia-Aedes suppression technology

Read on for a more detailed look at the biology behind Wolbachia-Aedes suppression technology. You’ll also find out more about the studies NEA has done to ensure that the male Wolbachia-Aedes mosquitoes we release will be effective at suppressing Aedes aegypti populations.

How was Wolbachia introduced into Aedes aegypti?

  • Although Wolbachia is found naturally in some mosquito species, Aedes aegypti does not naturally carry Wolbachia.
  • To introduce Wolbachia into Aedes aegypti, researchers injected the bacterium into Aedes aegypti eggs. This eventually produced adult Aedes aegypti that carried Wolbachia. Click here to find out more about egg microinjection.

egg microinjection

How does NEA mass-produce Wolbachia-Aedes mosquitoes for release?

  • Wolbachia is maternally transmitted. Female Wolbachia-carrying Aedes aegypti pass the bacterium down to their offspring, thus generating a stable line of Wolbachia-Aedes mosquitoes.
  • Rearing this line in NEA’s mosquito production facility allows us to easily produce large numbers of male Wolbachia-Aedes mosquitoes for our releases, without the need for further egg microinjection.
  • Click here to find out how NEA makes sure that the male Wolbachia-Aedes mosquitoes we release continue to carry Wolbachia.
Production of Wolbachia-Aedes mosquitoes

How do we get a population of only male Aedes aegypti?

  • Male and female mosquito pupae can be sorted by size, as male pupae are smaller than female pupae. How many male pupae are there in the picture below?

          Male mosquito pupae are smaller than female pupae                 Male and female mosquito pupae can be sorted by size

Why do matings between Wolbachia-Aedes males and urban non-Wolbachia-carrying females produce eggs that do not hatch?

  • Such matings are biologically incompatible due to a phenomenon called cytoplasmic incompatibility (CI), which is caused by Wolbachia.
  • Click here to find out about more about CI, and how NEA confirmed that CI works in our Wolbachia-Aedes mosquitoes.  

Can our lab-reared Wolbachia-Aedes males compete with wildtype males for female mosquitoes?

  • NEA’s studies have shown that Wolbachia does not affect the mating ability of our Wolbachia-Aedes males. Click here to find out about these studies.