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A shocking one-third of Americans believe this Zika conspiracy theory

The mosquito ‘Aedes aegypti’, which transmits the Zika virus, in a laboratory. (Image credit: EPA/OSCAR RIVERA)

This story has been updated.

Fear and misinformation about the Zika virus still abound, according to a new survey just released by the University of Pennsylvania’s Annenberg Public Policy Center. Most notably, the survey finds that more than a third of respondents incorrectly believe that genetically modified mosquitoes have caused the spread of the disease.

The survey, which was conducted this month by telephone, included 1,014 respondents in the U.S. It included eight questions probing participants’ knowledge about the disease and its transmission and their level of concern about it. Some questions suggested a high level of knowledge about the disease on certain fronts. Ninety-one percent of respondents were aware that mosquitoes transmit the virus, for instance, and two-thirds of respondents said they were familiar with news reports about Zika.

On the other hand, fewer than half of the participants correctly identified Brazil as the country with the largest current Zika outbreak. Nearly 20 percent of respondents incorrectly believe that it’s possible to contract the virus by sitting next to an infected person. In fact, Zika is primarily transmitted by infected mosquitoes, although it could also be contracted by blood or sexual contact with an infected person.

And, yes, 35 percent of respondents said they believed genetically modified mosquitoes have caused the spread of the virus. For this question, participants were given a choice about which scenario most closely matched their views: genetically modified mosquitoes caused the spread of the Zika virus, genetically modified mosquitoes could minimize the spread or the Zika virus, neither or don’t know. 

The idea that genetically modified mosquitoes contributed to the spread of Zika is a myth that began making the rounds back in January, fueled by a spate of speculative articles in the media. The rumors suggested that the outbreak of Zika in Brazil was caused by British biotechnology company Oxitec, which was conducting trials of a genetically modified mosquito in the country. The Oxitec mosquito is essentially sterile — its offspring die before they make it to adulthood. When released outdoors and allowed to breed with regular mosquitoes, the intended effect is to reduce wild mosquito populations. In fact, the major goal of its design is to reduce the transmission of mosquito-borne diseases.

The idea that the modified mosquitoes were somehow responsible for the Zika outbreak has been roundly debunked by experts — but the survey suggests that this misinformation is still widespread within the general public. On a more optimistic note, however, for the same question 43 percent of respondents said they believe the modified mosquito could actually help stop the spread of the virus.

Other survey questions indicated high levels of both concern and optimism, as far as the disease is concerned. Fifty-one percent of respondents said they were concerned, in some capacity, that Zika would spread to their location. It’s a possibility that has received mixed responses from experts, although many have deemed it unlikely.

So far, there have been no mosquito-borne cases of Zika transmission in the U.S., although a few travel-related cases have cropped up in the past few months. And while the CDC has noted that Zika will likely continue to spread in the Americas — and it’s possible that it could reach the States — many experts have also said that an outbreak on the scale of what’s happening in Brazil is unlikely. Outbreaks of other mosquito-borne diseases in the U.S., such as dengue fever, have generally been isolated and small in scale.

While concern among the U.S. public seems to nevertheless be running high, nearly two-thirds of respondents also said they were optimistic that the CDC would develop a vaccine against Zika by the end of the summer. Scientists in the U.S. and elsewhere are indeed researching a vaccine — but as for having one ready by the end of the summer, it remains up in the air. Officials at the National Institutes of Health recently said that human trials of a Zika vaccine could begin in a few months at the earliest. However, officials from the World Health Organization have suggested that it may be another 18 months or so.

As the outbreak in South America rages on, the survey’s results overall suggest that interest in the virus remains high — but so do the many fears and misconceptions that so often accompany an epidemic. And still other rumors, not addressed in this survey, continue to fly the longer the epidemic goes on. Most recently, a rash of articles have emerged suggesting that the uptick in microcephaly in Brazil has been caused by pesticide use, rather than the Zika virus — an idea that has also been largely dismissed by experts.

So while public awareness of a growing international concern is good, making sure the public has its facts straight on all fronts is better. As the survey indicates, clear communication of the best science remains key to avoid misinformation and hysteria when it comes to Zika and any similar situations in the future.

Clarification: This story was updated to more clearly note that the question which asked respondents about genetically modified mosquitoes only allowed a limited number of answer choices.