WASHINGTON — When it comes to online conspiracy theories, Sen. Kamala Harris’ campaign follows the old mantra: Sunlight is the best disinfectant.

Traditionally, political public relations teams avoid commenting on conspiracies, misinformation or base insinuations about their clients, believing that calling attention to them dignifies and thus elevates them from the fringes.

But Harris’ communications team has been doing the opposite — immediately calling out material it sees as baseless.

Veterans of Democratic presidential campaigns say other campaigns should take note, because the strategy reflects a new normal in politics.

Former President Barack Obama and the Democrats’ 2016 presidential nominee, Hillary Clinton, were plagued by false conspiracy theories, from questioning of Obama’s place of birth (Hawaii) to rumors of Clinton health problems. The internet and social media allow these types of theories to grow and fester, and both candidates were eventually forced to respond. There’s every indication the 2020 presidential field will face more such attacks, enhanced by a voracious political extremist media sphere and foreign propaganda efforts.

Harris’ team has already begun confronting misinformation online, from the seedy to the silly.

When conspiracy theorist Jacob Wohl tweeted that Harris was ineligible to be president because her immigrant parents hadn’t lived in this country for five years before she was born, the California senator’s campaign communications director, Lily Adams, retweeted it and called it out as “garbage” within five minutes. Wohl’s assertion was fictitious: Harris is eligible to run for president as a U.S.-born citizen under the Constitution, and there are no natural-born citizenship requirements regarding parents’ status.

This type of stuff was garbage in 2008 and it’s garbage now. https://t.co/npUp1yHroq — Lily Adams (@adamslily) January 22, 2019

The campaign even wades in when the underlying controversy seems silly. During an interview with radio show “The Breakfast Club,” Harris revealed that she had smoked marijuana in college and talked about music she has listened to, including Snoop Dogg and Tupac. Some listeners blended the answers together, causing a mild internet storm when people pointed out that those artists weren’t performing when the 54-year-old Harris was in college.

Harris campaign spokesman Ian Sams went on offense to dispel the confusion, tweeting out video of the remarks and deriding Harris’ critics for “trying to make Reefergate happen.”

He also jumped in when Harris made a barbecue pit stop in South Carolina and a conservative radio host tweeted a roundabout allegation that Harris was promoting climate change by eating beef — cattle production being a notorious emitter of methane gas.

But Sams noted within minutes that in fact, “It was pork.”

The rightwing is so desperate to attack @KamalaHarris they're trying to make Reefergate happen.@djenvy asked what she listened to. @cthagod made a pot joke. Then she answered @djenvy's question.



This really isn't that complicated. Just watch. pic.twitter.com/jIuRLFUULF — Ian Sams (@IanSams) February 12, 2019

The campaign declined to comment for this story, but political communications specialists who are not working with any current presidential candidates say the lean-in approach of the Harris communications shop is a model of what campaigns will need to do this election cycle.

“I don’t think there’s any option to ignore anything anymore,” said Brian Fallon, who was Clinton’s presidential campaign press secretary and now runs the left-aligned advocacy group Demand Justice. “Any 2020 campaign’s press operation is wise to be constantly monitoring what gets picked up on Twitter, essentially, and to immediately speak to debunk and contain rather than wish it would go away.”

In previous eras, campaigns could wait and see what the media ran with. With the internet, that cycle has been shortened from days to minutes. Most newsrooms monitor Twitter to see what gets traction, and some assign stories accordingly.

Sometimes, what gets traction is Trump’s Twitter feed itself. It’s easy for Democratic campaigns to see the benefits of trying to grab hold of the narrative on social media — as Trump does nearly every day.

To stay ahead of the news cycle, Fallon said, smart campaigns will capitalize on the same social media environment to control what’s being said about the candidate. A campaign’s silence or slowness to respond to circulating allegations could be interpreted as “panic mode,” he added.

“Twitter, I think, has become something of an assignment editor in recent years,” Fallon said. “Only like 20 percent of the general public is on Twitter, but basically 100 percent of political reporters are on Twitter. ... So engaging immediately and confidently and providing new facts and context is a must.”

The need for rapid response is made even more urgent by the revelations about Russia’s propaganda efforts during the 2016 election, which U.S. intelligence agencies concluded were designed to promote Trump’s candidacy. Those operations promoted conspiracy theories online to harm Trump’s rivals and sow political discord.

The Department of Homeland Security has pledged that the administration will combat any such efforts in the 2020 campaign, amid concerns that Trump’s own diminishing of Russian election disruption would carry over into the administration’s work. Chris Krebs, director of the Cybersecurity and Infrastructure Security Agency, said in a recent call with reporters that his office would help “anybody who comes knocking on our door.”

Even so, former Obama campaign press secretary Ben LaBolt agrees that ignoring conspiracy theories is no longer a luxury that campaigns can enjoy. He should know — false theories about Obama’s birthplace plagued the president for years. The persistent queries eventually forced him to release two copies of his birth certificate as he lamented the unfounded rumors as “silliness,” adding that “normally (he) would not comment on something like this.”

The notion that responding to a conspiracy theory elevates it is also a thing of the past, LaBolt said. He noted that Trump still promotes conspiracy theories on Twitter and elsewhere without checking on their veracity, from tweeting baselessly about “rigged” Google search results to falsely implying that his 2016 opponent Sen. Ted Cruz’s father was involved in John F. Kennedy’s assassination.

“We live in a world where you can’t even necessarily trust what’s coming out of the president of the United States’ mouth, and he’s not going to check his sources before he tweets something out,” LaBolt said. “Once things are in the ecosystem, they’re in an environment with no editors, and it’s the campaign’s responsibility to serve as those editors.”

Given the president’s history of promoting such theories, effectively defusing them is in some ways a test of candidates’ abilities to stand up to Trump, said Jesse Ferguson, a Democratic strategist and former Clinton campaign spokesman.

“Democrats want a (nominee) that can defeat Donald Trump, and one way to demonstrate that is aggressively taking on the type of conspiracies that he fosters, thrives on and promotes,” Ferguson said. “There’s no candidate who will succeed this cycle without confronting the right-wing conspiracy fever, and defeating fraudulent memes about them.”

Tal Kopan is The San Francisco Chronicle’s Washington correspondent. Email: tal.kopan@sfchronicle.com Twitter: @talkopan