Wednesday, March 2, 2016

The Zika Conspiracy

Photograph by Felipe Dana/AP

In most cases, Zika is so mild that people can become infected and never know it.
But the virus has also been associated with an otherwise-rare birth defect in which babies are born with abnormally small heads and underdeveloped brains, a condition known as microcephaly.
It is also suspected of having caused Guillain-Barré syndrome, which leads to (an almost always temporary) paralysis.
It is too soon for epidemiologists to have proven those links beyond question, but few, if any, experts doubt them.
These facts have left many people terrified, which is understandable. There is no treatment for Zika, and no vaccine. This is a serious virus, and we don’t know much about it yet.
But we do know the Zika virus, which, like dengue fever, is transmitted by the Aedes aegypti mosquito, was first recognized in 1947, in Uganda.
Conspiracy theories flow constantly across the Internet. And one such theory that may be hard to ignore relates to the Zika scourge.
I first came to know about it when I stumbled upon a Michael Specter article in The New Yorker. It seems that more than a third of the Americans surveyed in a poll, out last week, from the University of Pennsylvania’s Annenberg Public Policy Center believe that genetically modified mosquitoes caused the spread of Zika.
This is a particularly dangerous misapprehension, because, for now, controlling mosquitoes may be the only way we can hope to control the mosquito-borne disease.
This myth seems to have grown out of a Reddit post on January 25, 2016 alleging that Oxitec, a UK company which began releasing genetically engineered male-sterile mosquitoes in north-eastern Brazil in order to combat dengue disease, may have inadvertently caused the Zika pestilence.
A scientific paper about the trials conducted in the Brazilian city of Juazeiro in late 2011, confirmed that the local population of disease-carrying Aedes aegypti mosquitoes crashed by more than 90 percent, making Oxitec’s approach a far more promising form of control than conventional insecticide spraying.
Aedes mosquitoes carry both dengue and Zika, so the same strategy could help tackle both diseases.
The Reddit post claimed to spot a correlation between the site of the GM mosquito releases and the location of the first Zika outbreaks in Brazil. This allegation was repeated on the fringe news site AntiMedia on January 28, three days later. It even included a handy map with a big red arrow indicating the mosquito release site in an area suspiciously close to the main Zika-affected locations.
It is conveniently forgotten that there are two cities called Juazeiro in Brazil – one in the Brazilian state of Bahia and the other in the nearby state of Ceará – and AntiMedia’s big red arrow was pointing at the wrong one, as the myth-busting science blogger Christie Wilcox promptly pointed out.
The Juazeiro where the GM mosquito releases had actually taken place was 300km away. Anyway, both cities are in turn rather a long way from the main Zika contagion areas, which are located on the coast.
The timing was wrong too. Zika was first reported in Brazil in 2015, while the Oxitec mosquito releases began four years earlier.
Moreover, Zika is thought to have come to Brazil from a 2013 plague in French Polynesia, which in turn spread from a 2007 outbreak in Micronesia.
Even UK’s Daily Mail picked up the story on January 31. “Are scientists to blame for Zika virus?” it asked, in a typically suggestive rhetorical question.
And this story has spread far and wide since.
The logic of the genetically-modified-mosquitoes conspiracy theory is hard to grasp: it has been at least four years since they were first released in Brazil. Human pregnancies last nine months. Surely some babies must have been born in the intervening three years.
Why were they spared the microcephaly if the genetically modified mosquitoes are to blame?
Moreover, the altered mosquitoes had previously been released in the Cayman Islands, Malaysia, and Panama without causing problems.
Viruses constantly spread and mutate, and that began long before humans arrived on Earth.
On Monday, Malaysian squash queen, Nicol David failed to progress into the last four of the 2016 Windy City Open (February 23-March 02, 2016) held in Chicago, USA when she lost to Egypt’s Nour El Sherbini 9-11, 10-12, 9-11 in thirty-six minutes.

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