Politics / Law
The human race is at war with another species, and has been for thousands of years. Each of us in Europe swats dead dozens of the enemy every summer, and in the tropics they kill thousands of people with infectious diseases...
The human race is at war with another species, and has been for thousands of years. Each of us in Europe swats dead dozens of the enemy every summer, and in the tropics they kill thousands of people with infectious diseases hidden within their bodies. As in all wars, the battle for public opinion plays a key role in hostilities, along with the latest high-tech weaponry. The newest front in our battle with bloodsucking insects is now a matter of public debate. Innovative and powerful bioengineering technologies are providing Homo sapiens with a potential game-changer in the war against disease-carrying mosquitos. Unfortunately, at some point the weapons have to be tested out in the field. Exactly how careful and transparent do researchers have to be in large-scale studies involving transgenic animals?
Since 2009, Oxford-based biotech company Oxitec Ltd has released millions of genetically altered Aedes mosquitoes – which transmit both yellow fever and dengue fever – in a field test on the island of Grand Cayman. In 2010 and 2011, the British bioengineers also began large-scale experiments in both Brazil and Malaysia. A long list of other countries where the diseases pose a major health concern are lining up to host field tests of their own. Strikingly, it took more than a year for the little-publicised studies to begin making headlines. But when they did, the ensuing uproar was loud, and many scientists have sided with environmental groups in voicing concerns about inadequate oversight in the emerging field.
The mosquitoes used in the Grand Cayman study were altered using Oxitec’s RIDL® technology, which produces insects that can only survive if as larvae they are also fed a particular supplement. Larvae born of matings between RIDL and wild-type mosquitoes live for awhile, competing with ‘healthy’ offspring. Without access to the supplement, however, these die before reaching maturity. The release of successive waves of transgenic adult male mosquitoes, so the theory, can help decimate populations of the dangerous disease-carriers.
And in fact, the first results from the Caribbean look positive. “We monitored the mosquito population very thoroughly for several months after the pilot study was conducted, and found an initial reduction in the population of around 80%,” said Bill Petrie, the Director of Cayman’s Mosquito Research & Control Unit. He also told the country’s news service in January that “these data refute any allegation that the released mosquitoes persisted in the environment.” Fears in the general public might revolve around being bitten by GM mosquitoes, but for experts, the persistence of the implanted genes in the wild population would be a worrying indicator that everything was not going according to plan.
A grave lack of transparency
Although the experiment has apparently gone well, Oxitec was widely condemned by NGOs and environmental organisations for not being more forthcoming about the study, even though it was approved by the Caymans government. Scientists are also concerned about gray areas and a lack of standards. In a paper published at the end of January in the open-access journal PLoS – Neglected Tropical Diseases, researchers from the Max Planck Institute for Evolutionary Biology took a close look at how different countries cope with oversight and public access to information on large-scale field tests with GM mosquitoes – and found them seriously lacking. In “Scientific standards and the regulation of genetically modified insects”, their assessment of the regulatory apparatus found that in field experiments performed with transgenic insects in the US so far, little was done to inform the public in advance that the tests were taking place, and there was no real public debate on the issue. There was also no estimate of possible hazards prior to the releases in the Caymans, Brazil or Malaysia.
“We noted that public access to scientific information is highly restricted throughout the world, particularly information made available before releases start,” said Guy Reeves, the paper’s lead author, who also pursues fundamental research in how to combat disease-carrying insects effectively with the help of bioengineering techniques. “We argue for transparency – not for transparency’s sake – but for clearly articulated strategic reasons that promote acceptance of the value of evaluating this promising technology,” he says.
Trying not to repeat mistakes
According to the WHO, up to 100 million people are infected with dengue fever every year. Around half a million of them, mostly children, end up in hospital. Up to 30,000 people die of the disease annually. Yellow fever kills around the same number. While there is an effective vaccine available for yellow fever, the only way to fight dengue at the moment is through vector control.
Scientists in the field agree that bioengineered insects could prove an effective weapon in controlling that host vector, but are divided on the best ways to move forward with the research. Oxitec has defended its quiet pursuit of large-scale testing by pointing out that government agencies in the affected countries approved the trials well in advance. And the company’s initial success has paid off in more than scientific terms. In February, Oxitec received £8m in fresh cash from investment fund Oxford Capital, and has also increased staff numbers.
But many other scientists and companies are desperate to avoid a media debacle like that surrounding GM crops in Europe. By ignoring public concerns in the early days of that technology, firms like Monsanto drove European consumers firmly into the anti-GMO camp, where they have remained to this day. Researchers active in the field of transgenic insects don’t want to see those mistakes repeated. “While it may appear naïve to argue for pre-release access to accurate scientific information and a high quality multi-disciplinary approach,” concludes the MPI researchers’ paper on standards, “it is in our opinion even more naïve to expect that the development of GM insect technologies will progress far in its absence.”B