NEA to release male Wolbachia-infected mosquitoes as part of field study in October

A comparison video showing a batch of mosquito eggs hatching while another batch does not, as part of a study to release male Aedes mosquitoes carrying Wolbachia.VIDEO: ENVIRONMENTAL HEALTH INSTITUTE/NEA

SINGAPORE -From October, some residents might notice more mosquitoes buzzing in their neighbourhoods.

But don't worry, these male Aedes mosquitoes do not bite or transmit disease. They are in fact the latest allies in Singapore's fight against dengue.

They will be armed with Wolbachia, a naturally occurring bacteria. When these male mosquitoes mate with female mosquitoes, the bacteria causes the females to produce eggs that do not hatch.

Over time, this method could lead to a fall in the Aedes aegypti population, which transmit the viruses that cause dengue fever. These mosquitoes also carry the Chikungunya and Zika viruses.

On Saturday (Aug 27), Environment and Water Resources Minister Masagos Zulkifli announced that the National Environment Agency (NEA) will release these bacteria-carrying mosquitoes at three sites as part of a small-scale field study.

The areas, Yishun Street 21, Tampines Avenue 4 and Jalan Riang/Jalan Sukachita in Serangoon, previously had dengue outbreaks and represent a cross-section of typical housing estates in Singapore.

 

Speaking to reporters at a public outreach event organised by NEA, Mr Masagos said that while efforts to reduce the mosquito population have been "fairly successful", Singapore is still susceptible to dengue outbreaks as it is located in a region where dengue is endemic.

The new method "works together with source eradication".

"Whatever we're doing today to ensure that mosquitoes don't have opportunity to breed must continue", he added.

The NEA estimated that an average of one to three male mosquitoes per person will be released at regular intervals at each of the three sites.

The six-month field study aims to understand the behaviour of Wolbachia-carrying Aedes aegypti in the urban environment, for instance, how far and high they fly, and how well they compete with their counterparts without Wolbachia to mate with females.

To collect data, NEA will be setting up traps at various locations, including public spaces and the homes of resident volunteers. The data will support the planning for a suppression trial, which may start in 2017.