The Zika virus outbreak currently gripping the Americas could have been sparked by the release of genetically modified mosquitoes in 2012, critics say.
The insects were engineered by biotechnology experts to combat the spread of dengue fever and other diseases and released into the general population of Brazil in 2012.
But with the World Health Organisation (WHO) now meeting in Geneva to desperately discuss cures for the Zika virus, speculation has mounted as to the cause of this sudden outbreak.
The Zika virus was first discovered in the 1950s but the recent outbreak has escalated alarmingly, causing birth defects and a range of health problems in South and central America.
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The first cases were reported in Brazil last May with up to 1.5 million people now thought to be affected by the virus which is spread by mosquitoes endemic to Latin America.
The Aedes aegypti mosquito sub-species that carries both the Zika virus and dengue was the type targeted with genetically modified mosquitoes.
The aim was to release only male Aedes mosquitoes into the wild and they would in turn produce offspring with their virus carrying female counterparts.
This offspring would then die off before breeding again due to the GM coding in their genes.
But experts expressed concerns about the programme at the time of its inception, arguing that further studies were needed on the potential consequences.