Growing A Mosquito Army To Fight Dengue

Challenge follows two National Environment Agency (NEA) officers for a closer look at what goes on behind the production and release of male Wolbachia-Aedes aegypti mosquitoes.
Mr Deng Lu, National Environment Agency (NEA) releasing male Wolbachia-Aedes adult mosquitos using his lightweight mosquito launcher he developed. Article Image
Mr Deng Lu uses a lightweight mosquito launcher that he developed to speed up the release of male Wolbachia-Aedes mosquitoes at an HDB estate corridor.

Mr Andy Yip “eats, sleeps and breathes” mosquitoes. At the National Environment Agency (NEA), the Senior Research Officer rears mosquitoes, in what he calls a “seven-day work week”. The team takes weekend shifts just to ensure that the mosquitoes are alive and kicking.

These are no ordinary mozzies. Under NEA’s “Project Wolbachia – Singapore”, male Aedes aegypti mosquitoes carrying the Wolbachia bacterium are released at selected field study sites. When these male Wolbachia-Aedes mosquitoes mate with female Aedes aegypti mosquitoes, the resulting eggs do not hatch. Over time, the mosquito population goes down. Already, the test site at Nee Soon East has seen an 80% reduction in mosquitoes.

To produce the Wolbachia-Aedes mosquitoes, the NEA team feeds, counts and sorts the larvae and pupae, then separates them by sex. It is a laborious and time-consuming effort.

Enter Mr Deng Lu, Senior Research Officer at the NEA Environmental Health Institute. The plucky innovator led the development of several inventions that automate and speed up the mosquito rearing process. A new larvae counter, for example, has reduced the time needed for counting larvae from two hours, done manually, to a two-minute automated process.

Other patent-pending inventions include a larvae feeder, a pupae dispensing system, and a mosquito launcher – all done in collaboration with local start-up Orinno Technology.

Mr Deng, whose background is in molecular and medical biology, picked up additional engineering skills in his quest to improve the mosquito production and release processes.

“I have a passion for physics and engineering, so it’s nice that I can merge physics, engineering and an understanding of mosquito biology to invent all this equipment,” Mr Deng says.

Producing Wolbachia-Aedes mosquito eggs

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From Wolbachia-Aedes eggs to adult mosquitoes

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Release of male Wolbachia-Aedes mosquitoes

MrDenglooksunderthecanistersofthemosquitolaunchertocheckthatthemosquitoesareactiveenoughtoflyoutoncereleasedAmotorisedfanbeneaththecanistershelpsthemosquitoestoflyout ThemaleWolbachia-AedesadultmosquitoesarereleasedalongHDBestatecorridorstwiceaweekinthemorningsatselectedstudysitesMrDengusesalightweightmosquitolauncherthathedevelopedtospeedupthereleaseofthemosquitoes
    Jun 6, 2019
    Wong Wing Lum
    Norman Ng
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