Malaysia has delayed a landmark field trial to release genetically modified mosquitoes designed to combat dengue fever, an official said Tuesday, following protests from environmentalists.
In the first experiment of its kind in Asia, 4,000-6,000 male Aedes aegypti mosquitoes were originally scheduled to be released by last month in a bid to fight dengue, which killed at least 134 people last year in Malaysia alone.
The insects have been engineered so that their offspring quickly die, curbing the growth of the population in a technique researchers hope could eventually eradicate the dengue mosquito altogether. Females of the Aedes species are responsible for spreading dengue.
The trial however prompted widespread concern among environmental groups, which asked the government to call off the tests, saying the GM mosquito could fail to prevent dengue and have unintended consequences.
A senior official from the Biosafety Department told AFP that the trial, which was to be carried out in two Malaysian states, has been postponed pending further discussion with residents in the trial areas.
"There are a lot of protests. We are now aiming to carry out the trial in the first half of 2011," said Mohamed Mohamad Salleh, the department's director of research and evaluation.
"The (health authorities) must get approval from the residents in those areas where the residents will be affected. If it is uninhabited site, approval must be granted by state government officers," he said.
Mohamed added that public forums will be held to explain the trial. The Environment Ministry has said it received more than 30 responses from local and international groups on the controversial trial.
Two weeks ago, 22 non-government organisations on public health and the environment wrote an open letter to the government asking it to cancel the trial and "instead invest in safer approaches to addressing dengue".
"While dengue is a very serious problem in Malaysia and needs to be urgently addressed, going down the GM path takes us into risky territory. Genetic engineering often results in unintended effects," the letter said.
"We do not know enough about the GM mosquitoes and how their interactions with non-GM mosquitoes in the wild, other species in the ecosystem, the dengue virus and human populations, will be affected."
Authorities have dismissed the fears and said the trial would be harmless as the GM mosquitoes could only live for a few days.
Dengue infection leads to a sudden onset of fever with severe headaches, muscle and joint pains, and rashes, which can lead to death if left untreated.
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