Wolbachia mosquito project expanded to larger area

Wolbachia mosquito project expanded to larger area

In a bid to fight Singapore's dengue problem, authorities will release Wolbachia-infected male Aedes mosquitos in more areas of Nee Soon and Tampines next month. After mating with such male mosquitos, the females lay eggs that do not hatch. Lek Wan Zhen reports.

SINGAPORE: More than 140 blocks of Housing Board flats in Nee Soon East and Tampines West will be participating in the next phase of a study by the National Environment Agency (NEA) to reduce the Aedes mosquito population and fight dengue.

Male Wolbachia-Aedes mosquitoes, which have been infected with the Wolbachia bacterium, will be released into the expanded test sites at the two estates in phase three of the Project Wolbachia.

When they mate with female Aedes mosquitoes, the eggs the females lay will not hatch, said NEA.

The expansion in study sites follows the success of phase two of the study, which was conducted between April 2018 and January 2019, at smaller areas in Nee Soon East and Tampines West.

Phase two of the field study was designed to address the challenges posed by Singapore’s densely built-up, high-rise urban landscape, said NEA. 

The release of male Wolbachia-Aedes mosquitoes from both high floors and the ground at residential blocks helped ensure a better distribution of the infected mosquitoes.

Nee Soon East had its Aedes mosquito population decrease by 80 per cent, while Tampines West saw a fall of 50 per cent.

Citing a similar study in Guangzhou, Professor Ary Hoffmann, Laureate Professor at the University of Melbourne, said that it is possible for the mosquito population to drastically decrease in the long run.

As such, the third phase of the study aims to determine the ways to continue suppressing the dengue-transmitting Aedes mosquito population in the sites where they were released.

Researchers will study the optimal number of male Wolbachia-Aedes mosquitoes to be released into the area during this period. 

The third phase, which begins in February, will involve the largest study site so far, reaching more than 13,000 households in Nee Soon East and Tampines West.

Editor's note: In an earlier version of this story, NEA stated that the third phase of the study will reach more than 52,000 households in Nee Soo East and Tampines West. NEA has corrected this figure to 13,000.

Source: CNA/zl(hm)