Researchers examined a selection of social media posts about the Zika virus, looking at posts placed on Facebook for one week in late June.

About 12 percent of the posts were classified as misleading. Most of those posts suggested that Zika virus was a way to depopulate developing nations or called the entire disease a hoax.
While most of the 200 posts contained useful and credible information, the researchers found that those spreading conspiracy theories or misinformation were most popular.
The most shared credible and useful post, for example, was a video of a WHO press briefing that was viewed 43,000 times and shared by 964 Facebook accounts. The most popular post spreading misinformation claimed Zika virus is a “fraudulent medical hoax” and was viewed over 530,000 times. That post was also shared by more than 19,600 people.

Source: Accurate Facebook posts about Zika virus were plentiful, not popular
The new story notes that combating misinformation on social media is very difficult.

Budak also said the new study may underestimate the spread of misinformation since it only evaluated popular posts. Some research suggests the spread of misinformation by people online is much greater than what the new study shows.
“They just don’t really check the credibility of the information,” she said. “They receive and just share it right away.”

This finding is may be applicable also to popular “memes” and political posts. Many of the most outlandish posts seem to receive the most likes and shares.