Russian trolls didn’t just meddle in the 2016 US presidential election. It turns out they also sought to interfere with how Americans debated vaccines on Twitter — but from both sides of the argument.

A new study, “Weaponized Health Communication: Twitter Bots and Russian Trolls Amplify the Vaccine Debate,” was published Thursday in the American Journal of Public Health. Its objective was to “understand how Twitter bots and trolls ... promote online health content.”

The research found that Russian trolls and bots took to Twitter to attack pro-vaccine and anti-vaccines movements in the United States.

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The strange online campaign seems to have had the goal of simply increasing hostility and divisions online, according to the New York Times.

“You see this pattern,” David A. Broniatowski, a computer engineer at George Washington University and lead author of the study, told the New York Times. “On guns, or race, these accounts take opposite sides in lots of debates. They’re about sowing discord.”

The study looked at 899 vaccine-related tweets from mid-2014 to late 2017, according to the New York Times.

Most tweets that were sent from users identified as spam or malware accounts were breeding anti-vaccine messages, but those identified as Russian trolls attacked both sides of the vaccine debate.

The anti-vax movement perpetuates ideas that go against scientific evidence, scaring parents and encouraging them not to vaccinate their children. Unvaccinated children become sick and are a perfect starting point for an epidemic.

Anti-vaxxers often believe there’s a connection between vaccination and autism, as well as other brain disorders, despite there being no scientific evidence supporting that theory.

Most of the anti-vaccine tweets used messaging around these kinds of theories. The pro-vaccine posts pointed out the lifesaving effects of vaccinations, talking about the need for mandatory vaccines, but some were also derogatory.

“You can’t fix stupidity. Let them die from measles, and I’m for #vaccination,” one of the tweets reads, according to the New York Times.

The Russians sometimes used odd messaging for an American audience, Broniatowski said.

Some went as far as claiming vaccines were part of an Illuminati plan, while others attemped to cause class hostility — saying “clean vaccines” were for the elite, the New York Times reported.

Tweets that contained the hashtag #VaccinateUS were linked to troll accounts with ties to the Internet Research Agency, a propaganda scam connected to the Kremlin.

Broniatowski called it “a failed campaign by Russian trolls.”

While trolling may sometimes seem harmless, the spread of misinformation like this could ultimately trigger a massive disease outbreak, just as the anti-vax sentiment has done by pushing against scientific evidence.

More than 21 million hospitalizations and 732,000 deaths among children born in the last 20 years will be prevented because of vaccinations, according to the Centers for Disease Control and Prevention (CDC).

Still, it is estimated that 1.4 million children under 5 worldwide still die each year due to lack of access to vaccines.