And the larvicide theory propagated by the Argentinian organization Physicians in Crop-Sprayed Towns grew loud enough to stop one Brazilian state from using the chemical in their water supply, and the federal Brazilian government was moved to dismiss the claims.

The outbreak, it seems, has created a breeding ground not just for the virus, but for conspiracy theories, which have hovered over the chaos of past epidemics as well. In 2014, for example, a Liberian newspaper accused the United States of using Ebola as a bioweapon. During the 2003 SARS outbreak, a couple of Russian medical experts speculated that the virus seemed to be man-made, which of course led conspiracy theorists down the bioweapon path again. And during the H1N1 outbreak of 2009, conspiracy theorists suggested that pharmaceutical companies caused it to reap a profit. (Conspiracy theorists had extra ammo in the vaccination campaign for H1N1. Let me tell you, anything involving vaccines opens up a whole new can of conspiracy worms.)

Is there something about these outbreaks of emerging diseases that makes them such fertile soil for conspiracies to grow in?

“There’s a group of people out there who have what we might call a conspiracy mentality,” says Joseph Uscinski, an associate professor of political science at the University of Miami, and author of American Conspiracy Theories. “[They] come up with conspiracy theories for everything that happens. There are a million conspiracy theories out there; most of them you will never ever hear of. The bigger or scarier an event seems to be, the more the conspiracy theories seem to come to the forefront. This is one of those cases.”

This is also why there are prominent conspiracy theories about JFK’s assassination, or 9/11. They’re big, scary events. And outbreaks are big, scary events that happen over a long period of time, providing ample opportunity for conspiracy theories to develop as researchers work to understand the disease and its spread.

With Zika right now, there’s an “informational void,” says Brendan Nyhan, an assistant professor of government at Dartmouth College. Scientists are working quickly to fill that void, but in the meantime, people still have questions that science just can’t answer definitively yet.

“When an outbreak happens, people understandably want to know where the disease came from and what governments and health agencies are doing to stop it from spreading,” Karen Douglas, a professor of social psychology at the University of Kent, told me in an email. “However, sometimes it's not exactly clear how governments and health agencies are responding, and sometimes messages from these sources are opaque, or full of scientific jargon that people don’t understand. When this happens, people become even more uncertain and scared. Research shows that these conditions provide fertile ground for conspiracy theories. People look for ways to deal with the aversive states of uncertainty.”