In November of 2012, Brazil began, rather controversially, to disperse genetically-modified mosquitoes in one of its warmer cities. Though most people living in large cities outside of the tropical belt rarely even have to worry about mosquitoes, much less diseases spread by mosquito bites, mosquito-spread diseases affect more than half of the world's countries.
As the effects of climate change worsen, the number of cities affected by diseases like dengue will only increase; and indeed, the past 50 years have seen the number of yearly infections increase to nearly 400 million, more than the population of Canada and the US combined.
As the effects of climate change worsen, the number of cities affected by diseases like dengue will only increase; and indeed, the past 50 years have seen the number of yearly infections increase to nearly 400 million, more than the population of Canada and the US combined.
Brazil's genetically-modified mosquitoes will not eradicate dengue, they will only lower the number of viable offspring in a given year. As Jeff Goldblum so eloquently put it in Jurassic Park: "Life breaks free, it expands to new territories and crashes through barriers, painfully, maybe even dangerously... nature finds a way."
In agreement with Jeff, The UK non-governmental organization GeneWatch argued that: "Some next-generation mutants [could] survive and that a temporary reduction in dengue fever could be counterproductive by lowering human immunity."
In agreement with Jeff, The UK non-governmental organization GeneWatch argued that: "Some next-generation mutants [could] survive and that a temporary reduction in dengue fever could be counterproductive by lowering human immunity."
The New York Times was also wary of potentially unforeseen consequences arising from transgenic mosquitoes. In Tanzania and Kenya, mosquitoes have adapted to mosquito nets, proving that "nature finds a way." If mosquitoes can adapt to nets, even a successful program that lowers the number of mosquitoes carrying diseases could in the future lead to a "surge through a population of humans without the cultural knowledge or
pharmaceuticals necessary to defend themselves against it."
More worrying, however, are the unintended consequences of eradicating mosquitoes from the ecosystem. We've spent most of our resources and time studying the destruction of mosquitoes instead of working to determine if mosquitoes are vital to the stability of certain ecosystems. In the same manner that Mao Zedong's Four Pests Campaign sought to eradicate mosquitoes, it also worked to eliminate: rats, flies, and sparrows.
The eradication of sparrows by the at-the-time nascent communist government led to the wild proliferation of crop-eating insects, with consequences that would result in the death of countless millions. Since dengue affects 110 countries, there is a very real possibility that one of them conducts a program that successfully eradicates Aedes aegypti the mosquito.
Once eradication is complete at a national level, it will only result in the restart of a cycle of population growth involving potentially hyper-evolved mosquitoes. The mosquitoes that we will encounter in the future will be harder to kill. In some scenarios, a resurgence in dengue fever manages to infect over 1 billion people.
There are no effective antiviral agents for dengue, so a genetic aberration in the virus that increases human mortality could cause more deaths than the 1918 flu pandemic -- which only infected half a billion people.
We have entered an era of genetic experimentation that promises to only provide a patch to the increasing problem of mosquito-borne diseases, just one of the many problems caused by a warming world.
We have entered an era of genetic experimentation that promises to only provide a patch to the increasing problem of mosquito-borne diseases, just one of the many problems caused by a warming world.
A warming world is something that mosquitoes are looking forward to, and in the words of Dr. John Balbus, a senior policy analyst at the National Institute for Environmental Health Sciences: "Scientists don't
want to be alarmist, but they have systematically underestimated the
threat."
