There it
is! On August 5, the U.S. Food and Drug Administration issued
a "Preliminary
Finding of No Significant Impact (FONSI) In Support of an Investigational Field
Trial of OX513A Aedes aegypti Mosquitoes". In practice,
this is the greenlight for releasing of genetically modified mosquitoes
in a field trial in Florida Keys. Genetically modified Aedes
aegypti mosquitoes generate offspring that die if they are not exposed
to the antibiotic tetracycline. It implies – according to researchers – that
they will die outside a lab. The method aims to reduce radically mosquito
populations that spread Zika and other viruses. According to the FDA
"the probability that the release of OX513A male mosquitoes would
result in toxic or allergenic effects in humans or other animals is negligible
based on the sponsor’s draft EA. Almost all of the OX513A mosquitoes released
for the investigational field trial will be male, and male mosquitoes do not
bite humans or other animals. They are therefore not expected to have any
direct impacts on human or animal health". The release of GM
mosquitoes is not expected immediately, various federal, state and local
requirements are still to be met, including the final approval of the Florida
Keys Mosquito Control District, yet the field trial is now in the final
straight and it is just a matter of time till it starts.
Notwithstanding the massive information campaign carried out by public health authorities, the majority of residents is still objecting to the trial. According to a recent poll 58 percent of Key Haven residents oppose the project, and 168,000 people have signed an online petition against the test (admittedly most of them are not resident in the area).
What are the main reasons of public concerns? Opponents mention three main risks. First, they draw attention on a general risk, related to interventions which aim to alter complex ecosystems. They claim that it would be impossible to predict the potential impact of measures aiming at eradicating a species. This is a good argument, but it is too encompassing. Actually it could be used for any kind of attempt to fight Aedes aegypti mosquitoes and the sole possible answer to this argument would be to give up the fight against mosquitoes. The second argument is more specific. Opponents argue that the method of separating males and females is not perfect and at least one in 10,000 GM mosquitoes (according to the figures provided by the company that produces GM Aedes aegypti) are female instead of male. Given that several hundred thousand mosquitoes have to be released, there is an actual risk that GM mosquitoes could bite human beings. Again, the argument would work if it did not take as granted that being bitten by a GM mosquito would be risky. Actually, such a risk is not supported either by any sound theoretical consideration, or by any experimental evidence. On the contrary, it has been proven that the genetically modified female mosquito bite is no different from that of a wild mosquito. Finally, opponents argue that – according to the producing company – 3 to 4 percent of the GM mosquito offspring would survive, and thus they are expected to disseminate the mutation, whose evolutionary impact is totally unpredictable. Still, this is a logic argument but is it strong enough to prevent a measure whose aim is to stop the outbreak of significant infectious diseases, such as Zika and Dengue?
There is still another argument against the mosquito eradication strategy, which has not yet been used by opponents but it is – at least to me – the most puzzling. Evidences are accumulating that the passage through vectors contributes to mitigate the disease severity (virulence). If one eradicates today vectors, it is likely that – soon or later - viruses will find new vectors, yet without benefiting any longer from existing attenuation mechanisms. Are we paving the way for future, more severe, outbreaks?
As anyone could see, the scientific debate is anything but easy. Said so, it is also apparent that this debate did not penetrate into the public opinion, and changes are that the field trial will start with the majority of residents, at least the "active" majority of them, opposing the trial itself and thinking to be victim of a plan driven by multinational corporations. Oxitect, the British company, which produces GM mosquitoes, carried out in 2012 a similar field trial in Brazil with the aim to prevent Dengue. Chance would have it that some initial Zika cases originated in the same area where GM mosquitoes were released, therefore some people argued that GM mosquitoes were responsible for the emerging of Zika. Indeed on February 2016, a poll conducted by the Annenberg Public Policy Center found that more than one-third of Americans believed Zika generated by GM mosquitoes. Oxitect was supported by the Bill and Melissa Gates Foundation, and the conspiracy theory went ahead by claiming that Zika was purposely created within the wider scope of an (alleged) Bill Gates' depopulation agenda. The Florida field trial would thus close a circle initiated by the same companies and corporations that are now claiming to have the solution of the problem.
At the end of the story, disaffection towards science and technology will still grow. Would the prize be worth it? This is a difficult question. What is certain is that the gap between experts, policy makers, and the public opinion is becoming wider instead of reducing. Once again, experts and policy makers confused information with communication, and failed to make risk communication a true priority.
Notwithstanding the massive information campaign carried out by public health authorities, the majority of residents is still objecting to the trial. According to a recent poll 58 percent of Key Haven residents oppose the project, and 168,000 people have signed an online petition against the test (admittedly most of them are not resident in the area).
What are the main reasons of public concerns? Opponents mention three main risks. First, they draw attention on a general risk, related to interventions which aim to alter complex ecosystems. They claim that it would be impossible to predict the potential impact of measures aiming at eradicating a species. This is a good argument, but it is too encompassing. Actually it could be used for any kind of attempt to fight Aedes aegypti mosquitoes and the sole possible answer to this argument would be to give up the fight against mosquitoes. The second argument is more specific. Opponents argue that the method of separating males and females is not perfect and at least one in 10,000 GM mosquitoes (according to the figures provided by the company that produces GM Aedes aegypti) are female instead of male. Given that several hundred thousand mosquitoes have to be released, there is an actual risk that GM mosquitoes could bite human beings. Again, the argument would work if it did not take as granted that being bitten by a GM mosquito would be risky. Actually, such a risk is not supported either by any sound theoretical consideration, or by any experimental evidence. On the contrary, it has been proven that the genetically modified female mosquito bite is no different from that of a wild mosquito. Finally, opponents argue that – according to the producing company – 3 to 4 percent of the GM mosquito offspring would survive, and thus they are expected to disseminate the mutation, whose evolutionary impact is totally unpredictable. Still, this is a logic argument but is it strong enough to prevent a measure whose aim is to stop the outbreak of significant infectious diseases, such as Zika and Dengue?
There is still another argument against the mosquito eradication strategy, which has not yet been used by opponents but it is – at least to me – the most puzzling. Evidences are accumulating that the passage through vectors contributes to mitigate the disease severity (virulence). If one eradicates today vectors, it is likely that – soon or later - viruses will find new vectors, yet without benefiting any longer from existing attenuation mechanisms. Are we paving the way for future, more severe, outbreaks?
As anyone could see, the scientific debate is anything but easy. Said so, it is also apparent that this debate did not penetrate into the public opinion, and changes are that the field trial will start with the majority of residents, at least the "active" majority of them, opposing the trial itself and thinking to be victim of a plan driven by multinational corporations. Oxitect, the British company, which produces GM mosquitoes, carried out in 2012 a similar field trial in Brazil with the aim to prevent Dengue. Chance would have it that some initial Zika cases originated in the same area where GM mosquitoes were released, therefore some people argued that GM mosquitoes were responsible for the emerging of Zika. Indeed on February 2016, a poll conducted by the Annenberg Public Policy Center found that more than one-third of Americans believed Zika generated by GM mosquitoes. Oxitect was supported by the Bill and Melissa Gates Foundation, and the conspiracy theory went ahead by claiming that Zika was purposely created within the wider scope of an (alleged) Bill Gates' depopulation agenda. The Florida field trial would thus close a circle initiated by the same companies and corporations that are now claiming to have the solution of the problem.
At the end of the story, disaffection towards science and technology will still grow. Would the prize be worth it? This is a difficult question. What is certain is that the gap between experts, policy makers, and the public opinion is becoming wider instead of reducing. Once again, experts and policy makers confused information with communication, and failed to make risk communication a true priority.
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